Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

221 files changed, 38375 insertions, 0 deletions

diff --git a/taskcluster/gecko_taskgraph/.ruff.toml b/taskcluster/gecko_taskgraph/.ruff.toml
new file mode 100644
index 0000000000..0cd744c1cb
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/.ruff.toml
@@ -0,0 +1,4 @@
+extend = "../../pyproject.toml"
+
+[isort]
+known-first-party = ["gecko_taskgraph"]
diff --git a/taskcluster/gecko_taskgraph/__init__.py b/taskcluster/gecko_taskgraph/__init__.py
new file mode 100644
index 0000000000..1346bf3c33
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/__init__.py
@@ -0,0 +1,64 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+
+from taskgraph import config as taskgraph_config
+from taskgraph import morph as taskgraph_morph
+from taskgraph.util import schema
+from taskgraph.util import taskcluster as tc_util
+
+from gecko_taskgraph.config import graph_config_schema
+
+GECKO = os.path.normpath(os.path.realpath(os.path.join(__file__, "..", "..", "..")))
+
+# Maximum number of dependencies a single task can have
+# https://firefox-ci-tc.services.mozilla.com/docs/reference/platform/queue/task-schema
+# specifies 100, but we also optionally add the decision task id as a dep in
+# taskgraph.create, so let's set this to 99.
+MAX_DEPENDENCIES = 99
+
+# Overwrite Taskgraph's default graph_config_schema with a custom one.
+taskgraph_config.graph_config_schema = graph_config_schema
+
+# Don't use any of the upstream morphs.
+# TODO Investigate merging our morphs with upstream.
+taskgraph_morph.registered_morphs = []
+
+# Default rootUrl to use if none is given in the environment; this should point
+# to the production Taskcluster deployment used for CI.
+tc_util.PRODUCTION_TASKCLUSTER_ROOT_URL = "https://firefox-ci-tc.services.mozilla.com"
+
+# Schemas for YAML files should use dashed identifiers by default. If there are
+# components of the schema for which there is a good reason to use another format,
+# exceptions can be added here.
+schema.EXCEPTED_SCHEMA_IDENTIFIERS.extend(
+    [
+        "test_name",
+        "json_location",
+        "video_location",
+    ]
+)
+
+
+def register(graph_config):
+    """Used to register Gecko specific extensions.
+
+    Args:
+        graph_config: The graph configuration object.
+    """
+    from taskgraph import generator
+
+    from gecko_taskgraph import (  # noqa: trigger target task method registration
+        morph,  # noqa: trigger morph registration
+        target_tasks,
+    )
+    from gecko_taskgraph.parameters import register_parameters
+    from gecko_taskgraph.util.verify import verifications
+
+    # Don't use the upstream verifications, and replace them with our own.
+    # TODO Investigate merging our verifications with upstream.
+    generator.verifications = verifications
+
+    register_parameters()
diff --git a/taskcluster/gecko_taskgraph/actions/__init__.py b/taskcluster/gecko_taskgraph/actions/__init__.py
new file mode 100644
index 0000000000..590a957282
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/__init__.py
@@ -0,0 +1,16 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from .registry import (
+    register_callback_action,
+    render_actions_json,
+    trigger_action_callback,
+)
+
+__all__ = [
+    "register_callback_action",
+    "render_actions_json",
+    "trigger_action_callback",
+]
diff --git a/taskcluster/gecko_taskgraph/actions/add_new_jobs.py b/taskcluster/gecko_taskgraph/actions/add_new_jobs.py
new file mode 100644
index 0000000000..39200cff68
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/add_new_jobs.py
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from .registry import register_callback_action
+from .util import combine_task_graph_files, create_tasks, fetch_graph_and_labels
+
+
+@register_callback_action(
+    name="add-new-jobs",
+    title="Add new jobs",
+    symbol="add-new",
+    description="Add new jobs using task labels.",
+    order=100,
+    context=[],
+    schema={
+        "type": "object",
+        "properties": {
+            "tasks": {
+                "type": "array",
+                "description": "An array of task labels",
+                "items": {"type": "string"},
+            },
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 100,
+                "title": "Times",
+                "description": "How many times to run each task.",
+            },
+        },
+    },
+)
+def add_new_jobs_action(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    to_run = []
+    for elem in input["tasks"]:
+        if elem in full_task_graph.tasks:
+            to_run.append(elem)
+        else:
+            raise Exception(f"{elem} was not found in the task-graph")
+
+    times = input.get("times", 1)
+    for i in range(times):
+        create_tasks(
+            graph_config,
+            to_run,
+            full_task_graph,
+            label_to_taskid,
+            parameters,
+            decision_task_id,
+            i,
+        )
+    combine_task_graph_files(list(range(times)))
diff --git a/taskcluster/gecko_taskgraph/actions/add_talos.py b/taskcluster/gecko_taskgraph/actions/add_talos.py
new file mode 100644
index 0000000000..56b0c49cc9
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/add_talos.py
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from ..target_tasks import standard_filter
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    name="run-all-talos",
+    title="Run All Talos Tests",
+    symbol="raT",
+    description="Add all Talos tasks to a push.",
+    order=150,
+    context=[],
+    schema={
+        "type": "object",
+        "properties": {
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 6,
+                "title": "Times",
+                "description": "How many times to run each task.",
+            }
+        },
+        "additionalProperties": False,
+    },
+)
+def add_all_talos(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    times = input.get("times", 1)
+    for i in range(times):
+        to_run = [
+            label
+            for label, entry in full_task_graph.tasks.items()
+            if "talos_try_name" in entry.attributes
+            and standard_filter(entry, parameters)
+        ]
+
+        create_tasks(
+            graph_config,
+            to_run,
+            full_task_graph,
+            label_to_taskid,
+            parameters,
+            decision_task_id,
+        )
+        logger.info(f"Scheduled {len(to_run)} talos tasks (time {i + 1}/{times})")
diff --git a/taskcluster/gecko_taskgraph/actions/backfill.py b/taskcluster/gecko_taskgraph/actions/backfill.py
new file mode 100644
index 0000000000..81f29394d6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/backfill.py
@@ -0,0 +1,426 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+import re
+import sys
+from functools import partial
+
+from taskgraph.util.taskcluster import get_task_definition
+
+from .registry import register_callback_action
+from .util import (
+    combine_task_graph_files,
+    create_tasks,
+    fetch_graph_and_labels,
+    get_decision_task_id,
+    get_pushes,
+    get_pushes_from_params_input,
+    trigger_action,
+)
+
+logger = logging.getLogger(__name__)
+SYMBOL_REGEX = re.compile("^(.*)-[a-z0-9]{11}-bk$")
+GROUP_SYMBOL_REGEX = re.compile("^(.*)-bk$")
+
+
+def input_for_support_action(revision, task, times=1, retrigger=True):
+    """Generate input for action to be scheduled.
+
+    Define what label to schedule with 'label'.
+    If it is a test task that uses explicit manifests add that information.
+    """
+    input = {
+        "label": task["metadata"]["name"],
+        "revision": revision,
+        "times": times,
+        # We want the backfilled tasks to share the same symbol as the originating task
+        "symbol": task["extra"]["treeherder"]["symbol"],
+        "retrigger": retrigger,
+    }
+
+    # Support tasks that are using manifest based scheduling
+    if task["payload"].get("env", {}).get("MOZHARNESS_TEST_PATHS"):
+        input["test_manifests"] = json.loads(
+            task["payload"]["env"]["MOZHARNESS_TEST_PATHS"]
+        )
+
+    return input
+
+
+@register_callback_action(
+    title="Backfill",
+    name="backfill",
+    permission="backfill",
+    symbol="Bk",
+    description=("Given a task schedule it on previous pushes in the same project."),
+    order=200,
+    context=[{}],  # This will be available for all tasks
+    schema={
+        "type": "object",
+        "properties": {
+            "depth": {
+                "type": "integer",
+                "default": 19,
+                "minimum": 1,
+                "maximum": 25,
+                "title": "Depth",
+                "description": (
+                    "The number of previous pushes before the current "
+                    "push to attempt to trigger this task on."
+                ),
+            },
+            "inclusive": {
+                "type": "boolean",
+                "default": False,
+                "title": "Inclusive Range",
+                "description": (
+                    "If true, the backfill will also retrigger the task "
+                    "on the selected push."
+                ),
+            },
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 10,
+                "title": "Times",
+                "description": (
+                    "The number of times to execute each job you are backfilling."
+                ),
+            },
+            "retrigger": {
+                "type": "boolean",
+                "default": True,
+                "title": "Retrigger",
+                "description": (
+                    "If False, the task won't retrigger on pushes that have already "
+                    "ran it."
+                ),
+            },
+        },
+        "additionalProperties": False,
+    },
+    available=lambda parameters: True,
+)
+def backfill_action(parameters, graph_config, input, task_group_id, task_id):
+    """
+    This action takes a task ID and schedules it on previous pushes (via support action).
+
+    To execute this action locally follow the documentation here:
+    https://firefox-source-docs.mozilla.org/taskcluster/actions.html#testing-the-action-locally
+    """
+    task = get_task_definition(task_id)
+    pushes = get_pushes_from_params_input(parameters, input)
+    failed = False
+    input_for_action = input_for_support_action(
+        revision=parameters["head_rev"],
+        task=task,
+        times=input.get("times", 1),
+        retrigger=input.get("retrigger", True),
+    )
+
+    for push_id in pushes:
+        try:
+            # The Gecko decision task can sometimes fail on a push and we need to handle
+            # the exception that this call will produce
+            push_decision_task_id = get_decision_task_id(parameters["project"], push_id)
+        except Exception:
+            logger.warning(f"Could not find decision task for push {push_id}")
+            # The decision task may have failed, this is common enough that we
+            # don't want to report an error for it.
+            continue
+
+        try:
+            trigger_action(
+                action_name="backfill-task",
+                # This lets the action know on which push we want to add a new task
+                decision_task_id=push_decision_task_id,
+                input=input_for_action,
+            )
+        except Exception:
+            logger.exception(f"Failed to trigger action for {push_id}")
+            failed = True
+
+    if failed:
+        sys.exit(1)
+
+
+def add_backfill_suffix(regex, symbol, suffix):
+    m = regex.match(symbol)
+    if m is None:
+        symbol += suffix
+    return symbol
+
+
+def backfill_modifier(task, input):
+    if task.label != input["label"]:
+        return task
+
+    logger.debug(f"Modifying test_manifests for {task.label}")
+    times = input.get("times", 1)
+
+    # Set task duplicates based on 'times' value.
+    if times > 1:
+        task.attributes["task_duplicates"] = times
+
+    # If the original task has defined test paths
+    test_manifests = input.get("test_manifests")
+    if test_manifests:
+        revision = input.get("revision")
+
+        task.attributes["test_manifests"] = test_manifests
+        task.task["payload"]["env"]["MOZHARNESS_TEST_PATHS"] = json.dumps(
+            test_manifests
+        )
+        # The name/label might have been modify in new_label, thus, change it here as well
+        task.task["metadata"]["name"] = task.label
+        th_info = task.task["extra"]["treeherder"]
+        # Use a job symbol of the originating task as defined in the backfill action
+        th_info["symbol"] = add_backfill_suffix(
+            SYMBOL_REGEX, th_info["symbol"], f"-{revision[0:11]}-bk"
+        )
+        if th_info.get("groupSymbol"):
+            # Group all backfilled tasks together
+            th_info["groupSymbol"] = add_backfill_suffix(
+                GROUP_SYMBOL_REGEX, th_info["groupSymbol"], "-bk"
+            )
+        task.task["tags"]["action"] = "backfill-task"
+    return task
+
+
+def do_not_modify(task):
+    return task
+
+
+def new_label(label, tasks):
+    """This is to handle the case when a previous push does not contain a specific task label
+    and we try to find a label we can reuse.
+
+    For instance, we try to backfill chunk #3, however, a previous push does not contain such
+    chunk, thus, we try to reuse another task/label.
+    """
+    begining_label, ending = label.rsplit("-", 1)
+    if ending.isdigit():
+        # We assume that the taskgraph has chunk #1 OR unnumbered chunk and we hijack it
+        if begining_label in tasks:
+            return begining_label
+        if begining_label + "-1" in tasks:
+            return begining_label + "-1"
+        raise Exception(f"New label ({label}) was not found in the task-graph")
+    else:
+        raise Exception(f"{label} was not found in the task-graph")
+
+
+@register_callback_action(
+    name="backfill-task",
+    title="Backfill task on a push.",
+    permission="backfill",
+    symbol="backfill-task",
+    description="This action is normally scheduled by the backfill action. "
+    "The intent is to schedule a task on previous pushes.",
+    order=500,
+    context=[],
+    schema={
+        "type": "object",
+        "properties": {
+            "label": {"type": "string", "description": "A task label"},
+            "revision": {
+                "type": "string",
+                "description": "Revision of the original push from where we backfill.",
+            },
+            "symbol": {
+                "type": "string",
+                "description": "Symbol to be used by the scheduled task.",
+            },
+            "test_manifests": {
+                "type": "array",
+                "default": [],
+                "description": "An array of test manifest paths",
+                "items": {"type": "string"},
+            },
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 10,
+                "title": "Times",
+                "description": (
+                    "The number of times to execute each job " "you are backfilling."
+                ),
+            },
+            "retrigger": {
+                "type": "boolean",
+                "default": True,
+                "title": "Retrigger",
+                "description": (
+                    "If False, the task won't retrigger on pushes that have already "
+                    "ran it."
+                ),
+            },
+        },
+    },
+)
+def add_task_with_original_manifests(
+    parameters, graph_config, input, task_group_id, task_id
+):
+    """
+    This action is normally scheduled by the backfill action. The intent is to schedule a test
+    task with the test manifests from the original task (if available).
+
+    The push in which we want to schedule a new task is defined by the parameters object.
+
+    To execute this action locally follow the documentation here:
+    https://firefox-source-docs.mozilla.org/taskcluster/actions.html#testing-the-action-locally
+    """
+    # This step takes a lot of time when executed locally
+    logger.info("Retreving the full task graph and labels.")
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    label = input.get("label")
+    if not input.get("retrigger") and label in label_to_taskid:
+        logger.info(
+            f"Skipping push with decision task ID {decision_task_id} as it already has this test."
+        )
+        return
+
+    if label not in full_task_graph.tasks:
+        label = new_label(label, full_task_graph.tasks)
+
+    to_run = [label]
+
+    logger.info("Creating tasks...")
+    create_tasks(
+        graph_config,
+        to_run,
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id,
+        suffix="0",
+        modifier=partial(backfill_modifier, input=input),
+    )
+
+    # TODO Implement a way to write out artifacts without assuming there's
+    # multiple sets of them so we can stop passing in "suffix".
+    combine_task_graph_files(["0"])
+
+
+@register_callback_action(
+    title="Backfill all browsertime",
+    name="backfill-all-browsertime",
+    permission="backfill",
+    symbol="baB",
+    description=(
+        "Schedule all browsertime tests for the current and previous push in the same project."
+    ),
+    order=800,
+    context=[],  # This will be available for all tasks
+    available=lambda parameters: True,
+)
+def backfill_all_browsertime(parameters, graph_config, input, task_group_id, task_id):
+    """
+    This action takes a revision and schedules it on previous pushes (via support action).
+
+    To execute this action locally follow the documentation here:
+    https://firefox-source-docs.mozilla.org/taskcluster/actions.html#testing-the-action-locally
+    """
+    pushes = get_pushes(
+        project=parameters["head_repository"],
+        end_id=int(parameters["pushlog_id"]),
+        depth=2,
+    )
+
+    for push_id in pushes:
+        try:
+            # The Gecko decision task can sometimes fail on a push and we need to handle
+            # the exception that this call will produce
+            push_decision_task_id = get_decision_task_id(parameters["project"], push_id)
+        except Exception:
+            logger.warning(f"Could not find decision task for push {push_id}")
+            # The decision task may have failed, this is common enough that we
+            # don't want to report an error for it.
+            continue
+
+        try:
+            trigger_action(
+                action_name="add-all-browsertime",
+                # This lets the action know on which push we want to add a new task
+                decision_task_id=push_decision_task_id,
+            )
+        except Exception:
+            logger.exception(f"Failed to trigger action for {push_id}")
+            sys.exit(1)
+
+
+def filter_raptor_jobs(full_task_graph, label_to_taskid):
+    to_run = []
+    for label, entry in full_task_graph.tasks.items():
+        if entry.kind != "test":
+            continue
+        if entry.task.get("extra", {}).get("suite", "") != "raptor":
+            continue
+        if "browsertime" not in entry.attributes.get("raptor_try_name", ""):
+            continue
+        if not entry.attributes.get("test_platform", "").endswith("shippable-qr/opt"):
+            continue
+        if "android" in entry.attributes.get("test_platform", ""):
+            # Bug 1786254 - The backfill bot is scheduling too many tests atm
+            continue
+        exceptions = ("live", "profiling", "youtube-playback")
+        if any(e in entry.attributes.get("raptor_try_name", "") for e in exceptions):
+            continue
+        if "firefox" in entry.attributes.get(
+            "raptor_try_name", ""
+        ) and entry.attributes.get("test_platform", "").endswith("64-shippable-qr/opt"):
+            # add the browsertime test
+            if label not in label_to_taskid:
+                to_run.append(label)
+        if "geckoview" in entry.attributes.get("raptor_try_name", ""):
+            # add the pageload test
+            if label not in label_to_taskid:
+                to_run.append(label)
+    return to_run
+
+
+@register_callback_action(
+    name="add-all-browsertime",
+    title="Add All Browsertime Tests.",
+    permission="backfill",
+    symbol="aaB",
+    description="This action is normally scheduled by the backfill-all-browsertime action. "
+    "The intent is to schedule all browsertime tests on a specific pushe.",
+    order=900,
+    context=[],
+)
+def add_all_browsertime(parameters, graph_config, input, task_group_id, task_id):
+    """
+    This action is normally scheduled by the backfill-all-browsertime action. The intent is to
+    trigger all browsertime tasks for the current revision.
+
+    The push in which we want to schedule a new task is defined by the parameters object.
+
+    To execute this action locally follow the documentation here:
+    https://firefox-source-docs.mozilla.org/taskcluster/actions.html#testing-the-action-locally
+    """
+    logger.info("Retreving the full task graph and labels.")
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    to_run = filter_raptor_jobs(full_task_graph, label_to_taskid)
+
+    create_tasks(
+        graph_config,
+        to_run,
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id,
+    )
+    logger.info(f"Scheduled {len(to_run)} raptor tasks (time 1)")
diff --git a/taskcluster/gecko_taskgraph/actions/cancel.py b/taskcluster/gecko_taskgraph/actions/cancel.py
new file mode 100644
index 0000000000..d895781395
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/cancel.py
@@ -0,0 +1,36 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+import requests
+from taskgraph.util.taskcluster import cancel_task
+
+from .registry import register_callback_action
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    title="Cancel Task",
+    name="cancel",
+    symbol="cx",
+    description=("Cancel the given task"),
+    order=350,
+    context=[{}],
+)
+def cancel_action(parameters, graph_config, input, task_group_id, task_id):
+    # Note that this is limited by the scopes afforded to generic actions to
+    # only cancel tasks with the level-specific schedulerId.
+    try:
+        cancel_task(task_id, use_proxy=True)
+    except requests.HTTPError as e:
+        if e.response.status_code == 409:
+            # A 409 response indicates that this task is past its deadline.  It
+            # cannot be cancelled at this time, but it's also not running
+            # anymore, so we can ignore this error.
+            logger.info(f"Task {task_id} is past its deadline and cannot be cancelled.")
+            return
+        raise
diff --git a/taskcluster/gecko_taskgraph/actions/cancel_all.py b/taskcluster/gecko_taskgraph/actions/cancel_all.py
new file mode 100644
index 0000000000..d74b83b7d8
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/cancel_all.py
@@ -0,0 +1,60 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import concurrent.futures as futures
+import logging
+import os
+
+import requests
+from taskgraph.util.taskcluster import CONCURRENCY, cancel_task
+
+from gecko_taskgraph.util.taskcluster import list_task_group_incomplete_task_ids
+
+from .registry import register_callback_action
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    title="Cancel All",
+    name="cancel-all",
+    symbol="cAll",
+    description=(
+        "Cancel all running and pending tasks created by the decision task "
+        "this action task is associated with."
+    ),
+    order=400,
+    context=[],
+)
+def cancel_all_action(parameters, graph_config, input, task_group_id, task_id):
+    def do_cancel_task(task_id):
+        logger.info(f"Cancelling task {task_id}")
+        try:
+            cancel_task(task_id, use_proxy=True)
+        except requests.HTTPError as e:
+            if e.response.status_code == 409:
+                # A 409 response indicates that this task is past its deadline.  It
+                # cannot be cancelled at this time, but it's also not running
+                # anymore, so we can ignore this error.
+                logger.info(
+                    "Task {} is past its deadline and cannot be cancelled.".format(
+                        task_id
+                    )
+                )
+                return
+            raise
+
+    own_task_id = os.environ.get("TASK_ID", "")
+    to_cancel = [
+        t
+        for t in list_task_group_incomplete_task_ids(task_group_id)
+        if t != own_task_id
+    ]
+
+    logger.info(f"Cancelling {len(to_cancel)} tasks")
+    with futures.ThreadPoolExecutor(CONCURRENCY) as e:
+        cancel_futs = [e.submit(do_cancel_task, t) for t in to_cancel]
+        for f in futures.as_completed(cancel_futs):
+            f.result()
diff --git a/taskcluster/gecko_taskgraph/actions/confirm_failure.py b/taskcluster/gecko_taskgraph/actions/confirm_failure.py
new file mode 100644
index 0000000000..3d0b572a2e
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/confirm_failure.py
@@ -0,0 +1,238 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+import re
+
+from taskgraph.util.parameterization import resolve_task_references
+from taskgraph.util.taskcluster import get_artifact, get_task_definition, list_artifacts
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+from .registry import register_callback_action
+from .util import add_args_to_command, create_task_from_def, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+
+def get_failures(task_id):
+    """Returns a dict containing properties containing a list of
+    directories containing test failures and a separate list of
+    individual test failures from the errorsummary.log artifact for
+    the task.
+
+    Calls the helper function munge_test_path to attempt to find an
+    appropriate test path to pass to the task in
+    MOZHARNESS_TEST_PATHS.  If no appropriate test path can be
+    determined, nothing is returned.
+    """
+
+    def re_compile_list(*lst):
+        # Ideally we'd just use rb"" literals and avoid the encode, but
+        # this file needs to be importable in python2 for now.
+        return [re.compile(s.encode("utf-8")) for s in lst]
+
+    re_bad_tests = re_compile_list(
+        r"Last test finished",
+        r"LeakSanitizer",
+        r"Main app process exited normally",
+        r"ShutdownLeaks",
+        r"[(]SimpleTest/TestRunner.js[)]",
+        r"automation.py",
+        r"https?://localhost:\d+/\d+/\d+/.*[.]html",
+        r"jsreftest",
+        r"leakcheck",
+        r"mozrunner-startup",
+        r"pid: ",
+        r"RemoteProcessMonitor",
+        r"unknown test url",
+    )
+    re_extract_tests = re_compile_list(
+        r'"test": "(?:[^:]+:)?(?:https?|file):[^ ]+/reftest/tests/([^ "]+)',
+        r'"test": "(?:[^:]+:)?(?:https?|file):[^:]+:[0-9]+/tests/([^ "]+)',
+        r'xpcshell-?[^ "]*\.ini:([^ "]+)',
+        r'/tests/([^ "]+) - finished .*',
+        r'"test": "([^ "]+)"',
+        r'"message": "Error running command run_test with arguments '
+        r"[(]<wptrunner[.]wpttest[.]TestharnessTest ([^>]+)>",
+        r'"message": "TEST-[^ ]+ [|] ([^ "]+)[^|]*[|]',
+    )
+
+    def munge_test_path(line):
+        test_path = None
+        for r in re_bad_tests:
+            if r.search(line):
+                return None
+        for r in re_extract_tests:
+            m = r.search(line)
+            if m:
+                test_path = m.group(1)
+                break
+        return test_path
+
+    # collect dirs that don't have a specific manifest
+    dirs = set()
+    tests = set()
+    artifacts = list_artifacts(task_id)
+    for artifact in artifacts:
+        if "name" not in artifact or not artifact["name"].endswith("errorsummary.log"):
+            continue
+
+        stream = get_artifact(task_id, artifact["name"])
+        if not stream:
+            continue
+
+        # We handle the stream as raw bytes because it may contain invalid
+        # UTF-8 characters in portions other than those containing the error
+        # messages we're looking for.
+        for line in stream.read().split(b"\n"):
+            if not line.strip():
+                continue
+
+            l = json.loads(line)
+            if "group_results" in l.keys() and l["status"] != "OK":
+                dirs.add(l["group_results"].group())
+
+            elif "test" in l.keys():
+                test_path = munge_test_path(line.strip())
+                tests.add(test_path.decode("utf-8"))
+
+                # only run the failing test not both test + dir
+                if l["group"] in dirs:
+                    dirs.remove(l["group"])
+
+            if len(tests) > 4:
+                break
+
+        # turn group into dir by stripping off leafname
+        dirs = set([d.split("/")[0:-1] for d in dirs])
+
+    return {"dirs": sorted(dirs), "tests": sorted(tests)}
+
+
+def create_confirm_failure_tasks(task_definition, failures, level):
+    """
+    Create tasks to re-run the original task plus tasks to test
+    each failing test directory and individual path.
+
+    """
+    logger.info(f"Confirm Failures task:\n{json.dumps(task_definition, indent=2)}")
+
+    # Operate on a copy of the original task_definition
+    task_definition = copy_task(task_definition)
+
+    task_name = task_definition["metadata"]["name"]
+    repeatable_task = False
+    if (
+        "crashtest" in task_name
+        or "mochitest" in task_name
+        or "reftest" in task_name
+        or "xpcshell" in task_name
+        and "jsreftest" not in task_name
+    ):
+        repeatable_task = True
+
+    th_dict = task_definition["extra"]["treeherder"]
+    symbol = th_dict["symbol"]
+    is_windows = "windows" in th_dict["machine"]["platform"]
+
+    suite = task_definition["extra"]["suite"]
+    if "-coverage" in suite:
+        suite = suite[: suite.index("-coverage")]
+    is_wpt = "web-platform-tests" in suite
+
+    # command is a copy of task_definition['payload']['command'] from the original task.
+    # It is used to create the new version containing the
+    # task_definition['payload']['command'] with repeat_args which is updated every time
+    # through the failure_group loop.
+
+    command = copy_task(task_definition["payload"]["command"])
+
+    th_dict["groupSymbol"] = th_dict["groupSymbol"] + "-cf"
+    th_dict["tier"] = 3
+
+    if repeatable_task:
+        task_definition["payload"]["maxRunTime"] = 3600 * 3
+
+    for failure_group in failures:
+        if len(failures[failure_group]) == 0:
+            continue
+        if failure_group == "dirs":
+            failure_group_suffix = "-d"
+            # execute 5 total loops
+            repeat_args = ["--repeat=4"] if repeatable_task else []
+        elif failure_group == "tests":
+            failure_group_suffix = "-t"
+            # execute 10 total loops
+            repeat_args = ["--repeat=9"] if repeatable_task else []
+        else:
+            logger.error(
+                "create_confirm_failure_tasks: Unknown failure_group {}".format(
+                    failure_group
+                )
+            )
+            continue
+
+        if repeat_args:
+            task_definition["payload"]["command"] = add_args_to_command(
+                command, extra_args=repeat_args
+            )
+        else:
+            task_definition["payload"]["command"] = command
+
+        for failure_path in failures[failure_group]:
+            th_dict["symbol"] = symbol + failure_group_suffix
+            if is_wpt:
+                failure_path = "testing/web-platform/tests" + failure_path
+            if is_windows:
+                failure_path = "\\".join(failure_path.split("/"))
+            task_definition["payload"]["env"]["MOZHARNESS_TEST_PATHS"] = json.dumps(
+                {suite: [failure_path]}, sort_keys=True
+            )
+
+            logger.info(
+                "Creating task for path {} with command {}".format(
+                    failure_path, task_definition["payload"]["command"]
+                )
+            )
+            create_task_from_def(task_definition, level)
+
+
+@register_callback_action(
+    name="confirm-failures",
+    title="Confirm failures in job",
+    symbol="cf",
+    description="Re-run Tests for original manifest, directories or tests for failing tests.",
+    order=150,
+    context=[{"kind": "test"}],
+    schema={
+        "type": "object",
+        "properties": {},
+        "additionalProperties": False,
+    },
+)
+def confirm_failures(parameters, graph_config, input, task_group_id, task_id):
+    task = get_task_definition(task_id)
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    pre_task = full_task_graph.tasks[task["metadata"]["name"]]
+
+    # fix up the task's dependencies, similar to how optimization would
+    # have done in the decision
+    dependencies = {
+        name: label_to_taskid[label] for name, label in pre_task.dependencies.items()
+    }
+
+    task_definition = resolve_task_references(
+        pre_task.label, pre_task.task, task_id, decision_task_id, dependencies
+    )
+    task_definition.setdefault("dependencies", []).extend(dependencies.values())
+
+    failures = get_failures(task_id)
+    logger.info("confirm_failures: %s" % failures)
+    create_confirm_failure_tasks(task_definition, failures, parameters["level"])
diff --git a/taskcluster/gecko_taskgraph/actions/create_interactive.py b/taskcluster/gecko_taskgraph/actions/create_interactive.py
new file mode 100644
index 0000000000..c8d196782e
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/create_interactive.py
@@ -0,0 +1,192 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import os
+import re
+
+import taskcluster_urls
+from taskgraph.util.taskcluster import get_root_url, get_task_definition, send_email
+
+from gecko_taskgraph.actions.registry import register_callback_action
+from gecko_taskgraph.actions.util import create_tasks, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+EMAIL_SUBJECT = "Your Interactive Task for {label}"
+EMAIL_CONTENT = """\
+As you requested, Firefox CI has created an interactive task to run {label}
+on revision {revision} in {repo}. Click the button below to connect to the
+task. You may need to wait for it to begin running.
+"""
+
+###
+# Security Concerns
+#
+# An "interactive task" is, quite literally, shell access to a worker. That
+# is limited by being in a Docker container, but we assume that Docker has
+# bugs so we do not want to rely on container isolation exclusively.
+#
+# Interactive tasks should never be allowed on hosts that build binaries
+# leading to a release -- level 3 builders.
+#
+# Users must not be allowed to create interactive tasks for tasks above
+# their own level.
+#
+# Interactive tasks must not have any routes that might make them appear
+# in the index to be used by other production tasks.
+#
+# Interactive tasks should not be able to write to any docker-worker caches.
+
+SCOPE_WHITELIST = [
+    # these are not actually secrets, and just about everything needs them
+    re.compile(r"^secrets:get:project/taskcluster/gecko/(hgfingerprint|hgmointernal)$"),
+    # public downloads are OK
+    re.compile(r"^docker-worker:relengapi-proxy:tooltool.download.public$"),
+    re.compile(r"^project:releng:services/tooltool/api/download/public$"),
+    # internal downloads are OK
+    re.compile(r"^docker-worker:relengapi-proxy:tooltool.download.internal$"),
+    re.compile(r"^project:releng:services/tooltool/api/download/internal$"),
+    # private toolchain artifacts from tasks
+    re.compile(r"^queue:get-artifact:project/gecko/.*$"),
+    # level-appropriate secrets are generally necessary to run a task; these
+    # also are "not that secret" - most of them are built into the resulting
+    # binary and could be extracted by someone with `strings`.
+    re.compile(r"^secrets:get:project/releng/gecko/build/level-[0-9]/\*"),
+    # ptracing is generally useful for interactive tasks, too!
+    re.compile(r"^docker-worker:feature:allowPtrace$"),
+    # docker-worker capabilities include loopback devices
+    re.compile(r"^docker-worker:capability:device:.*$"),
+    re.compile(r"^docker-worker:capability:privileged$"),
+    re.compile(r"^docker-worker:cache:gecko-level-1-checkouts.*$"),
+    re.compile(r"^docker-worker:cache:gecko-level-1-tooltool-cache.*$"),
+]
+
+
+def context(params):
+    # available for any docker-worker tasks at levels 1, 2; and for
+    # test tasks on level 3 (level-3 builders are firewalled off)
+    if int(params["level"]) < 3:
+        return [{"worker-implementation": "docker-worker"}]
+    return [{"worker-implementation": "docker-worker", "kind": "test"}]
+    # Windows is not supported by one-click loaners yet. See
+    # https://wiki.mozilla.org/ReleaseEngineering/How_To/Self_Provision_a_TaskCluster_Windows_Instance
+    # for instructions for using them.
+
+
+@register_callback_action(
+    title="Create Interactive Task",
+    name="create-interactive",
+    symbol="create-inter",
+    description=("Create a a copy of the task that you can interact with"),
+    order=50,
+    context=context,
+    schema={
+        "type": "object",
+        "properties": {
+            "notify": {
+                "type": "string",
+                "format": "email",
+                "title": "Who to notify of the pending interactive task",
+                "description": (
+                    "Enter your email here to get an email containing a link "
+                    "to interact with the task"
+                ),
+                # include a default for ease of users' editing
+                "default": "noreply@noreply.mozilla.org",
+            },
+        },
+        "additionalProperties": False,
+    },
+)
+def create_interactive_action(parameters, graph_config, input, task_group_id, task_id):
+    # fetch the original task definition from the taskgraph, to avoid
+    # creating interactive copies of unexpected tasks.  Note that this only applies
+    # to docker-worker tasks, so we can assume the docker-worker payload format.
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    task = get_task_definition(task_id)
+    label = task["metadata"]["name"]
+
+    def edit(task):
+        if task.label != label:
+            return task
+        task_def = task.task
+
+        # drop task routes (don't index this!)
+        task_def["routes"] = []
+
+        # only try this once
+        task_def["retries"] = 0
+
+        # short expirations, at least 3 hour maxRunTime
+        task_def["deadline"] = {"relative-datestamp": "12 hours"}
+        task_def["created"] = {"relative-datestamp": "0 hours"}
+        task_def["expires"] = {"relative-datestamp": "1 day"}
+
+        # filter scopes with the SCOPE_WHITELIST
+        task.task["scopes"] = [
+            s
+            for s in task.task.get("scopes", [])
+            if any(p.match(s) for p in SCOPE_WHITELIST)
+        ]
+
+        payload = task_def["payload"]
+
+        # make sure the task runs for long enough..
+        payload["maxRunTime"] = max(3600 * 3, payload.get("maxRunTime", 0))
+
+        # no caches or artifacts
+        payload["cache"] = {}
+        payload["artifacts"] = {}
+
+        # enable interactive mode
+        payload.setdefault("features", {})["interactive"] = True
+        payload.setdefault("env", {})["TASKCLUSTER_INTERACTIVE"] = "true"
+
+        for key in task_def["payload"]["env"].keys():
+            payload["env"][key] = task_def["payload"]["env"].get(key, "")
+
+        return task
+
+    # Create the task and any of its dependencies. This uses a new taskGroupId to avoid
+    # polluting the existing taskGroup with interactive tasks.
+    action_task_id = os.environ.get("TASK_ID")
+    label_to_taskid = create_tasks(
+        graph_config,
+        [label],
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id=action_task_id,
+        modifier=edit,
+    )
+
+    taskId = label_to_taskid[label]
+    logger.info(f"Created interactive task {taskId}; sending notification")
+
+    if input and "notify" in input:
+        email = input["notify"]
+        # no point sending to a noreply address!
+        if email == "noreply@noreply.mozilla.org":
+            return
+
+        info = {
+            "url": taskcluster_urls.ui(get_root_url(False), f"tasks/{taskId}/connect"),
+            "label": label,
+            "revision": parameters["head_rev"],
+            "repo": parameters["head_repository"],
+        }
+        send_email(
+            email,
+            subject=EMAIL_SUBJECT.format(**info),
+            content=EMAIL_CONTENT.format(**info),
+            link={
+                "text": "Connect",
+                "href": info["url"],
+            },
+            use_proxy=True,
+        )
diff --git a/taskcluster/gecko_taskgraph/actions/gecko_profile.py b/taskcluster/gecko_taskgraph/actions/gecko_profile.py
new file mode 100644
index 0000000000..ce4394e77c
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/gecko_profile.py
@@ -0,0 +1,138 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+import requests
+from requests.exceptions import HTTPError
+from taskgraph.taskgraph import TaskGraph
+from taskgraph.util.taskcluster import get_artifact_from_index, get_task_definition
+
+from gecko_taskgraph.util.taskgraph import find_decision_task
+
+from .registry import register_callback_action
+from .util import combine_task_graph_files, create_tasks
+
+PUSHLOG_TMPL = "{}/json-pushes?version=2&startID={}&endID={}"
+INDEX_TMPL = "gecko.v2.{}.pushlog-id.{}.decision"
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    title="GeckoProfile",
+    name="geckoprofile",
+    symbol="Gp",
+    description=(
+        "Take the label of the current task, "
+        "and trigger the task with that label "
+        "on previous pushes in the same project "
+        "while adding the --gecko-profile cmd arg."
+    ),
+    order=200,
+    context=[{"test-type": "talos"}, {"test-type": "raptor"}],
+    schema={},
+    available=lambda parameters: True,
+)
+def geckoprofile_action(parameters, graph_config, input, task_group_id, task_id):
+    task = get_task_definition(task_id)
+    label = task["metadata"]["name"]
+    pushes = []
+    depth = 2
+    end_id = int(parameters["pushlog_id"])
+
+    while True:
+        start_id = max(end_id - depth, 0)
+        pushlog_url = PUSHLOG_TMPL.format(
+            parameters["head_repository"], start_id, end_id
+        )
+        r = requests.get(pushlog_url)
+        r.raise_for_status()
+        pushes = pushes + list(r.json()["pushes"].keys())
+        if len(pushes) >= depth:
+            break
+
+        end_id = start_id - 1
+        start_id -= depth
+        if start_id < 0:
+            break
+
+    pushes = sorted(pushes)[-depth:]
+    backfill_pushes = []
+
+    for push in pushes:
+        try:
+            full_task_graph = get_artifact_from_index(
+                INDEX_TMPL.format(parameters["project"], push),
+                "public/full-task-graph.json",
+            )
+            _, full_task_graph = TaskGraph.from_json(full_task_graph)
+            label_to_taskid = get_artifact_from_index(
+                INDEX_TMPL.format(parameters["project"], push),
+                "public/label-to-taskid.json",
+            )
+            push_params = get_artifact_from_index(
+                INDEX_TMPL.format(parameters["project"], push), "public/parameters.yml"
+            )
+            push_decision_task_id = find_decision_task(push_params, graph_config)
+        except HTTPError as e:
+            logger.info(f"Skipping {push} due to missing index artifacts! Error: {e}")
+            continue
+
+        if label in full_task_graph.tasks.keys():
+
+            def modifier(task):
+                if task.label != label:
+                    return task
+
+                cmd = task.task["payload"]["command"]
+                task.task["payload"]["command"] = add_args_to_perf_command(
+                    cmd, ["--gecko-profile"]
+                )
+                task.task["extra"]["treeherder"]["symbol"] += "-p"
+                task.task["extra"]["treeherder"]["groupName"] += " (profiling)"
+                return task
+
+            create_tasks(
+                graph_config,
+                [label],
+                full_task_graph,
+                label_to_taskid,
+                push_params,
+                push_decision_task_id,
+                push,
+                modifier=modifier,
+            )
+            backfill_pushes.append(push)
+        else:
+            logging.info(f"Could not find {label} on {push}. Skipping.")
+    combine_task_graph_files(backfill_pushes)
+
+
+def add_args_to_perf_command(payload_commands, extra_args=[]):
+    """
+    Add custom command line args to a given command.
+    args:
+      payload_commands: the raw command as seen by taskcluster
+      extra_args: array of args we want to inject
+    """
+    perf_command_idx = -1  # currently, it's the last (or only) command
+    perf_command = payload_commands[perf_command_idx]
+
+    command_form = "default"
+    if isinstance(perf_command, str):
+        # windows has a single command, in long string form
+        perf_command = perf_command.split(" ")
+        command_form = "string"
+    # osx & linux have an array of subarrays
+
+    perf_command.extend(extra_args)
+
+    if command_form == "string":
+        # pack it back to list
+        perf_command = " ".join(perf_command)
+
+    payload_commands[perf_command_idx] = perf_command
+    return payload_commands
diff --git a/taskcluster/gecko_taskgraph/actions/merge_automation.py b/taskcluster/gecko_taskgraph/actions/merge_automation.py
new file mode 100644
index 0000000000..8b9455536b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/merge_automation.py
@@ -0,0 +1,99 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.parameters import Parameters
+
+from gecko_taskgraph.actions.registry import register_callback_action
+from gecko_taskgraph.decision import taskgraph_decision
+from gecko_taskgraph.util.attributes import RELEASE_PROMOTION_PROJECTS
+
+
+def is_release_promotion_available(parameters):
+    return parameters["project"] in RELEASE_PROMOTION_PROJECTS
+
+
+@register_callback_action(
+    name="merge-automation",
+    title="Merge Day Automation",
+    symbol="${input.behavior}",
+    description="Merge repository branches.",
+    permission="merge-automation",
+    order=500,
+    context=[],
+    available=is_release_promotion_available,
+    schema=lambda graph_config: {
+        "type": "object",
+        "properties": {
+            "force-dry-run": {
+                "type": "boolean",
+                "description": "Override other options and do not push changes",
+                "default": True,
+            },
+            "push": {
+                "type": "boolean",
+                "description": "Push changes using to_repo and to_branch",
+                "default": False,
+            },
+            "behavior": {
+                "type": "string",
+                "description": "The type of release promotion to perform.",
+                "enum": sorted(graph_config["merge-automation"]["behaviors"].keys()),
+                "default": "central-to-beta",
+            },
+            "from-repo": {
+                "type": "string",
+                "description": "The URI of the source repository",
+            },
+            "to-repo": {
+                "type": "string",
+                "description": "The push URI of the target repository",
+            },
+            "from-branch": {
+                "type": "string",
+                "description": "The fx head of the source, such as central",
+            },
+            "to-branch": {
+                "type": "string",
+                "description": "The fx head of the target, such as beta",
+            },
+            "ssh-user-alias": {
+                "type": "string",
+                "description": "The alias of an ssh account to use when pushing changes.",
+            },
+            "fetch-version-from": {
+                "type": "string",
+                "description": "Path to file used when querying current version.",
+            },
+        },
+        "required": ["behavior"],
+    },
+)
+def merge_automation_action(parameters, graph_config, input, task_group_id, task_id):
+
+    # make parameters read-write
+    parameters = dict(parameters)
+
+    parameters["target_tasks_method"] = "merge_automation"
+    parameters["merge_config"] = {
+        "force-dry-run": input.get("force-dry-run", False),
+        "behavior": input["behavior"],
+    }
+
+    for field in [
+        "from-repo",
+        "from-branch",
+        "to-repo",
+        "to-branch",
+        "ssh-user-alias",
+        "push",
+        "fetch-version-from",
+    ]:
+        if input.get(field):
+            parameters["merge_config"][field] = input[field]
+    parameters["tasks_for"] = "action"
+
+    # make parameters read-only
+    parameters = Parameters(**parameters)
+
+    taskgraph_decision({"root": graph_config.root_dir}, parameters=parameters)
diff --git a/taskcluster/gecko_taskgraph/actions/openh264.py b/taskcluster/gecko_taskgraph/actions/openh264.py
new file mode 100644
index 0000000000..226817f696
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/openh264.py
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels
+
+
+@register_callback_action(
+    name="openh264",
+    title="OpenH264 Binaries",
+    symbol="h264",
+    description="Action to prepare openh264 binaries for shipping",
+    context=[],
+)
+def openh264_action(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    to_run = [
+        label
+        for label, entry in full_task_graph.tasks.items()
+        if "openh264" in entry.kind
+    ]
+    create_tasks(
+        graph_config,
+        to_run,
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id,
+    )
diff --git a/taskcluster/gecko_taskgraph/actions/purge_caches.py b/taskcluster/gecko_taskgraph/actions/purge_caches.py
new file mode 100644
index 0000000000..4905526f6c
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/purge_caches.py
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from taskgraph.util.taskcluster import get_task_definition, purge_cache
+
+from .registry import register_callback_action
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    title="Purge Worker Caches",
+    name="purge-cache",
+    symbol="purge-cache",
+    description=(
+        "Purge any caches associated with this task "
+        "across all workers of the same workertype as the task."
+    ),
+    order=450,
+    context=[{"worker-implementation": "docker-worker"}],
+)
+def purge_caches_action(parameters, graph_config, input, task_group_id, task_id):
+    task = get_task_definition(task_id)
+    if task["payload"].get("cache"):
+        for cache in task["payload"]["cache"]:
+            purge_cache(
+                task["provisionerId"], task["workerType"], cache, use_proxy=True
+            )
+    else:
+        logger.info("Task has no caches. Will not clear anything!")
diff --git a/taskcluster/gecko_taskgraph/actions/raptor_extra_options.py b/taskcluster/gecko_taskgraph/actions/raptor_extra_options.py
new file mode 100644
index 0000000000..43b26d284d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/raptor_extra_options.py
@@ -0,0 +1,77 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from taskgraph.util.taskcluster import get_task_definition
+
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    title="Raptor Extra Options",
+    name="raptor-extra-options",
+    symbol="rxo",
+    description=(
+        "Allows the user to rerun raptor-browsertime tasks with additional arguments."
+    ),
+    order=200,
+    context=[{"test-type": "raptor"}],
+    schema={
+        "type": "object",
+        "properties": {
+            "extra_options": {
+                "type": "string",
+                "default": "",
+                "description": "A space-delimited string of extra options "
+                "to be passed into a raptor-browsertime test."
+                "This also works with options with values, where the values "
+                "should be set as an assignment e.g. browser-cycles=3 "
+                "Passing multiple extra options could look something this:  "
+                "`verbose browser-cycles=3` where the test runs with verbose "
+                "mode on and the browser cycles only 3 times.",
+            }
+        },
+    },
+    available=lambda parameters: True,
+)
+def raptor_extra_options_action(
+    parameters, graph_config, input, task_group_id, task_id
+):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    task = get_task_definition(task_id)
+    label = task["metadata"]["name"]
+
+    def modifier(task):
+        if task.label != label:
+            return task
+
+        if task.task["payload"]["env"].get("PERF_FLAGS"):
+            task.task["payload"]["env"]["PERF_FLAGS"] += " " + input.get(
+                "extra_options"
+            )
+        else:
+            task.task["payload"]["env"].setdefault(
+                "PERF_FLAGS", input.get("extra_options")
+            )
+
+        task.task["extra"]["treeherder"]["symbol"] += "-rxo"
+        task.task["extra"]["treeherder"]["groupName"] += " (extra options run)"
+        return task
+
+    create_tasks(
+        graph_config,
+        [label],
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id,
+        modifier=modifier,
+    )
diff --git a/taskcluster/gecko_taskgraph/actions/rebuild_cached_tasks.py b/taskcluster/gecko_taskgraph/actions/rebuild_cached_tasks.py
new file mode 100644
index 0000000000..9d8906caf1
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/rebuild_cached_tasks.py
@@ -0,0 +1,37 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels
+
+
+@register_callback_action(
+    name="rebuild-cached-tasks",
+    title="Rebuild Cached Tasks",
+    symbol="rebuild-cached",
+    description="Rebuild cached tasks.",
+    order=1000,
+    context=[],
+)
+def rebuild_cached_tasks_action(
+    parameters, graph_config, input, task_group_id, task_id
+):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    cached_tasks = [
+        label
+        for label, task in full_task_graph.tasks.items()
+        if task.attributes.get("cached_task", False)
+    ]
+    if cached_tasks:
+        create_tasks(
+            graph_config,
+            cached_tasks,
+            full_task_graph,
+            label_to_taskid,
+            parameters,
+            decision_task_id,
+        )
diff --git a/taskcluster/gecko_taskgraph/actions/registry.py b/taskcluster/gecko_taskgraph/actions/registry.py
new file mode 100644
index 0000000000..0c99e68d20
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/registry.py
@@ -0,0 +1,371 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import re
+from collections import namedtuple
+from types import FunctionType
+
+from mozbuild.util import memoize
+from taskgraph import create
+from taskgraph.config import load_graph_config
+from taskgraph.parameters import Parameters
+from taskgraph.util import taskcluster, yaml
+from taskgraph.util.python_path import import_sibling_modules
+
+from gecko_taskgraph.util import hash
+
+actions = []
+callbacks = {}
+
+Action = namedtuple("Action", ["order", "cb_name", "permission", "action_builder"])
+
+
+def is_json(data):
+    """Return ``True``, if ``data`` is a JSON serializable data structure."""
+    try:
+        json.dumps(data)
+    except ValueError:
+        return False
+    return True
+
+
+@memoize
+def read_taskcluster_yml(filename):
+    """Load and parse .taskcluster.yml, memoized to save some time"""
+    return yaml.load_yaml(filename)
+
+
+@memoize
+def hash_taskcluster_yml(filename):
+    """
+    Generate a hash of the given .taskcluster.yml.  This is the first 10 digits
+    of the sha256 of the file's content, and is used by administrative scripts
+    to create a hook based on this content.
+    """
+    return hash.hash_path(filename)[:10]
+
+
+def register_callback_action(
+    name,
+    title,
+    symbol,
+    description,
+    order=10000,
+    context=[],
+    available=lambda parameters: True,
+    schema=None,
+    permission="generic",
+    cb_name=None,
+):
+    """
+    Register an action callback that can be triggered from supporting
+    user interfaces, such as Treeherder.
+
+    This function is to be used as a decorator for a callback that takes
+    parameters as follows:
+
+    ``parameters``:
+        Decision task parameters, see ``taskgraph.parameters.Parameters``.
+    ``input``:
+        Input matching specified JSON schema, ``None`` if no ``schema``
+        parameter is given to ``register_callback_action``.
+    ``task_group_id``:
+        The id of the task-group this was triggered for.
+    ``task_id`` and `task``:
+        task identifier and task definition for task the action was triggered
+        for, ``None`` if no ``context`` parameters was given to
+        ``register_callback_action``.
+
+    Parameters
+    ----------
+    name : str
+        An identifier for this action, used by UIs to find the action.
+    title : str
+        A human readable title for the action to be used as label on a button
+        or text on a link for triggering the action.
+    symbol : str
+        Treeherder symbol for the action callback, this is the symbol that the
+        task calling your callback will be displayed as. This is usually 1-3
+        letters abbreviating the action title.
+    description : str
+        A human readable description of the action in **markdown**.
+        This will be display as tooltip and in dialog window when the action
+        is triggered. This is a good place to describe how to use the action.
+    order : int
+        Order of the action in menus, this is relative to the ``order`` of
+        other actions declared.
+    context : list of dict
+        List of tag-sets specifying which tasks the action is can take as input.
+        If no tag-sets is specified as input the action is related to the
+        entire task-group, and won't be triggered with a given task.
+
+        Otherwise, if ``context = [{'k': 'b', 'p': 'l'}, {'k': 't'}]`` will only
+        be displayed in the context menu for tasks that has
+        ``task.tags.k == 'b' && task.tags.p = 'l'`` or ``task.tags.k = 't'``.
+        Esentially, this allows filtering on ``task.tags``.
+
+        If this is a function, it is given the decision parameters and must return
+        a value of the form described above.
+    available : function
+        An optional function that given decision parameters decides if the
+        action is available. Defaults to a function that always returns ``True``.
+    schema : dict
+        JSON schema specifying input accepted by the action.
+        This is optional and can be left ``null`` if no input is taken.
+    permission : string
+        This defaults to ``generic`` and needs to be set for actions that need
+        additional permissions. It appears appears in ci-configuration and
+        various role and hook
+        names.
+    cb_name : string
+        The name under which this function should be registered, defaulting to
+        `name`.  Unlike `name`, which can appear multiple times, cb_name must be
+        unique among all registered callbacks.
+
+    Returns
+    -------
+    function
+        To be used as decorator for the callback function.
+    """
+    mem = {"registered": False}  # workaround nonlocal missing in 2.x
+
+    assert isinstance(title, str), "title must be a string"
+    assert isinstance(description, str), "description must be a string"
+    title = title.strip()
+    description = description.strip()
+
+    if not cb_name:
+        cb_name = name
+
+    # ensure that context is callable
+    if not callable(context):
+        context_value = context
+
+        # Because of the same name as param it must be redefined
+        # pylint: disable=E0102
+        def context(params):
+            return context_value  # noqa
+
+    def register_callback(cb):
+        assert isinstance(name, str), "name must be a string"
+        assert isinstance(order, int), "order must be an integer"
+        assert callable(schema) or is_json(
+            schema
+        ), "schema must be a JSON compatible object"
+        assert isinstance(cb, FunctionType), "callback must be a function"
+        # Allow for json-e > 25 chars in the symbol.
+        if "$" not in symbol:
+            assert 1 <= len(symbol) <= 25, "symbol must be between 1 and 25 characters"
+        assert isinstance(symbol, str), "symbol must be a string"
+
+        assert not mem[
+            "registered"
+        ], "register_callback_action must be used as decorator"
+        assert cb_name not in callbacks, "callback name {} is not unique".format(
+            cb_name
+        )
+
+        def action_builder(parameters, graph_config, decision_task_id):
+            if not available(parameters):
+                return None
+
+            # gather up the common decision-task-supplied data for this action
+            repo_param = "{}head_repository".format(
+                graph_config["project-repo-param-prefix"]
+            )
+            repository = {
+                "url": parameters[repo_param],
+                "project": parameters["project"],
+                "level": parameters["level"],
+            }
+
+            revision = parameters[
+                "{}head_rev".format(graph_config["project-repo-param-prefix"])
+            ]
+            base_revision = parameters[
+                "{}base_rev".format(graph_config["project-repo-param-prefix"])
+            ]
+            push = {
+                "owner": "mozilla-taskcluster-maintenance@mozilla.com",
+                "pushlog_id": parameters["pushlog_id"],
+                "revision": revision,
+                "base_revision": base_revision,
+            }
+
+            match = re.match(
+                r"https://(hg.mozilla.org)/(.*?)/?$", parameters[repo_param]
+            )
+            if not match:
+                raise Exception(f"Unrecognized {repo_param}")
+            action = {
+                "name": name,
+                "title": title,
+                "description": description,
+                # target taskGroupId (the task group this decision task is creating)
+                "taskGroupId": decision_task_id,
+                "cb_name": cb_name,
+                "symbol": symbol,
+            }
+
+            rv = {
+                "name": name,
+                "title": title,
+                "description": description,
+                "context": context(parameters),
+            }
+            if schema:
+                rv["schema"] = (
+                    schema(graph_config=graph_config) if callable(schema) else schema
+                )
+
+            trustDomain = graph_config["trust-domain"]
+            level = parameters["level"]
+            tcyml_hash = hash_taskcluster_yml(graph_config.taskcluster_yml)
+
+            # the tcyml_hash is prefixed with `/` in the hookId, so users will be granted
+            # hooks:trigger-hook:project-gecko/in-tree-action-3-myaction/*; if another
+            # action was named `myaction/release`, then the `*` in the scope would also
+            # match that action.  To prevent such an accident, we prohibit `/` in hook
+            # names.
+            if "/" in permission:
+                raise Exception("`/` is not allowed in action names; use `-`")
+
+            rv.update(
+                {
+                    "kind": "hook",
+                    "hookGroupId": f"project-{trustDomain}",
+                    "hookId": "in-tree-action-{}-{}/{}".format(
+                        level, permission, tcyml_hash
+                    ),
+                    "hookPayload": {
+                        # provide the decision-task parameters as context for triggerHook
+                        "decision": {
+                            "action": action,
+                            "repository": repository,
+                            "push": push,
+                        },
+                        # and pass everything else through from our own context
+                        "user": {
+                            "input": {"$eval": "input"},
+                            "taskId": {"$eval": "taskId"},  # target taskId (or null)
+                            "taskGroupId": {
+                                "$eval": "taskGroupId"
+                            },  # target task group
+                        },
+                    },
+                    "extra": {
+                        "actionPerm": permission,
+                    },
+                }
+            )
+
+            return rv
+
+        actions.append(Action(order, cb_name, permission, action_builder))
+
+        mem["registered"] = True
+        callbacks[cb_name] = cb
+        return cb
+
+    return register_callback
+
+
+def render_actions_json(parameters, graph_config, decision_task_id):
+    """
+    Render JSON object for the ``public/actions.json`` artifact.
+
+    Parameters
+    ----------
+    parameters : taskgraph.parameters.Parameters
+        Decision task parameters.
+
+    Returns
+    -------
+    dict
+        JSON object representation of the ``public/actions.json`` artifact.
+    """
+    assert isinstance(parameters, Parameters), "requires instance of Parameters"
+    actions = []
+    for action in sorted(_get_actions(graph_config), key=lambda action: action.order):
+        action = action.action_builder(parameters, graph_config, decision_task_id)
+        if action:
+            assert is_json(action), "action must be a JSON compatible object"
+            actions.append(action)
+    return {
+        "version": 1,
+        "variables": {},
+        "actions": actions,
+    }
+
+
+def sanity_check_task_scope(callback, parameters, graph_config):
+    """
+    If this action is not generic, then verify that this task has the necessary
+    scope to run the action. This serves as a backstop preventing abuse by
+    running non-generic actions using generic hooks. While scopes should
+    prevent serious damage from such abuse, it's never a valid thing to do.
+    """
+    for action in _get_actions(graph_config):
+        if action.cb_name == callback:
+            break
+    else:
+        raise Exception(f"No action with cb_name {callback}")
+
+    repo_param = "{}head_repository".format(graph_config["project-repo-param-prefix"])
+    head_repository = parameters[repo_param]
+    assert head_repository.startswith("https://hg.mozilla.org/")
+    expected_scope = "assume:repo:{}:action:{}".format(
+        head_repository[8:], action.permission
+    )
+
+    # the scope should appear literally; no need for a satisfaction check. The use of
+    # get_current_scopes here calls the auth service through the Taskcluster Proxy, giving
+    # the precise scopes available to this task.
+    if expected_scope not in taskcluster.get_current_scopes():
+        raise Exception(f"Expected task scope {expected_scope} for this action")
+
+
+def trigger_action_callback(
+    task_group_id, task_id, input, callback, parameters, root, test=False
+):
+    """
+    Trigger action callback with the given inputs. If `test` is true, then run
+    the action callback in testing mode, without actually creating tasks.
+    """
+    graph_config = load_graph_config(root)
+    graph_config.register()
+    callbacks = _get_callbacks(graph_config)
+    cb = callbacks.get(callback, None)
+    if not cb:
+        raise Exception(
+            "Unknown callback: {}. Known callbacks: {}".format(
+                callback, ", ".join(callbacks)
+            )
+        )
+
+    if test:
+        create.testing = True
+        taskcluster.testing = True
+
+    if not test:
+        sanity_check_task_scope(callback, parameters, graph_config)
+
+    cb(Parameters(**parameters), graph_config, input, task_group_id, task_id)
+
+
+def _load(graph_config):
+    # Load all modules from this folder, relying on the side-effects of register_
+    # functions to populate the action registry.
+    import_sibling_modules(exceptions=("util.py",))
+    return callbacks, actions
+
+
+def _get_callbacks(graph_config):
+    return _load(graph_config)[0]
+
+
+def _get_actions(graph_config):
+    return _load(graph_config)[1]
diff --git a/taskcluster/gecko_taskgraph/actions/release_promotion.py b/taskcluster/gecko_taskgraph/actions/release_promotion.py
new file mode 100644
index 0000000000..9d6b7ad0b7
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/release_promotion.py
@@ -0,0 +1,426 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+
+import requests
+from taskgraph.parameters import Parameters
+from taskgraph.taskgraph import TaskGraph
+from taskgraph.util.taskcluster import get_artifact, list_task_group_incomplete_tasks
+
+from gecko_taskgraph.actions.registry import register_callback_action
+from gecko_taskgraph.decision import taskgraph_decision
+from gecko_taskgraph.util.attributes import RELEASE_PROMOTION_PROJECTS, release_level
+from gecko_taskgraph.util.partials import populate_release_history
+from gecko_taskgraph.util.partners import (
+    fix_partner_config,
+    get_partner_config_by_url,
+    get_partner_url_config,
+    get_token,
+)
+from gecko_taskgraph.util.taskgraph import (
+    find_decision_task,
+    find_existing_tasks_from_previous_kinds,
+)
+
+RELEASE_PROMOTION_SIGNOFFS = ("mar-signing",)
+
+
+def is_release_promotion_available(parameters):
+    return parameters["project"] in RELEASE_PROMOTION_PROJECTS
+
+
+def get_partner_config(partner_url_config, github_token):
+    partner_config = {}
+    for kind, url in partner_url_config.items():
+        if url:
+            partner_config[kind] = get_partner_config_by_url(url, kind, github_token)
+    return partner_config
+
+
+def get_signoff_properties():
+    props = {}
+    for signoff in RELEASE_PROMOTION_SIGNOFFS:
+        props[signoff] = {
+            "type": "string",
+        }
+    return props
+
+
+def get_required_signoffs(input, parameters):
+    input_signoffs = set(input.get("required_signoffs", []))
+    params_signoffs = set(parameters["required_signoffs"] or [])
+    return sorted(list(input_signoffs | params_signoffs))
+
+
+def get_signoff_urls(input, parameters):
+    signoff_urls = parameters["signoff_urls"]
+    signoff_urls.update(input.get("signoff_urls", {}))
+    return signoff_urls
+
+
+def get_flavors(graph_config, param):
+    """
+    Get all flavors with the given parameter enabled.
+    """
+    promotion_flavors = graph_config["release-promotion"]["flavors"]
+    return sorted(
+        flavor
+        for (flavor, config) in promotion_flavors.items()
+        if config.get(param, False)
+    )
+
+
+@register_callback_action(
+    name="release-promotion",
+    title="Release Promotion",
+    symbol="${input.release_promotion_flavor}",
+    description="Promote a release.",
+    permission="release-promotion",
+    order=500,
+    context=[],
+    available=is_release_promotion_available,
+    schema=lambda graph_config: {
+        "type": "object",
+        "properties": {
+            "build_number": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "title": "The release build number",
+                "description": (
+                    "The release build number. Starts at 1 per "
+                    "release version, and increments on rebuild."
+                ),
+            },
+            "do_not_optimize": {
+                "type": "array",
+                "description": (
+                    "Optional: a list of labels to avoid optimizing out "
+                    "of the graph (to force a rerun of, say, "
+                    "funsize docker-image tasks)."
+                ),
+                "items": {
+                    "type": "string",
+                },
+            },
+            "revision": {
+                "type": "string",
+                "title": "Optional: revision to promote",
+                "description": (
+                    "Optional: the revision to promote. If specified, "
+                    "and `previous_graph_kinds is not specified, find the "
+                    "push graph to promote based on the revision."
+                ),
+            },
+            "release_promotion_flavor": {
+                "type": "string",
+                "description": "The flavor of release promotion to perform.",
+                "default": "FILL ME OUT",
+                "enum": sorted(graph_config["release-promotion"]["flavors"].keys()),
+            },
+            "rebuild_kinds": {
+                "type": "array",
+                "description": (
+                    "Optional: an array of kinds to ignore from the previous "
+                    "graph(s)."
+                ),
+                "items": {
+                    "type": "string",
+                },
+            },
+            "previous_graph_ids": {
+                "type": "array",
+                "description": (
+                    "Optional: an array of taskIds of decision or action "
+                    "tasks from the previous graph(s) to use to populate "
+                    "our `previous_graph_kinds`."
+                ),
+                "items": {
+                    "type": "string",
+                },
+            },
+            "version": {
+                "type": "string",
+                "description": (
+                    "Optional: override the version for release promotion. "
+                    "Occasionally we'll land a taskgraph fix in a later "
+                    "commit, but want to act on a build from a previous "
+                    "commit. If a version bump has landed in the meantime, "
+                    "relying on the in-tree version will break things."
+                ),
+                "default": "",
+            },
+            "next_version": {
+                "type": "string",
+                "description": (
+                    "Next version. Required in the following flavors: "
+                    "{}".format(get_flavors(graph_config, "version-bump"))
+                ),
+                "default": "",
+            },
+            # Example:
+            #   'partial_updates': {
+            #       '38.0': {
+            #           'buildNumber': 1,
+            #           'locales': ['de', 'en-GB', 'ru', 'uk', 'zh-TW']
+            #       },
+            #       '37.0': {
+            #           'buildNumber': 2,
+            #           'locales': ['de', 'en-GB', 'ru', 'uk']
+            #       }
+            #   }
+            "partial_updates": {
+                "type": "object",
+                "description": (
+                    "Partial updates. Required in the following flavors: "
+                    "{}".format(get_flavors(graph_config, "partial-updates"))
+                ),
+                "default": {},
+                "additionalProperties": {
+                    "type": "object",
+                    "properties": {
+                        "buildNumber": {
+                            "type": "number",
+                        },
+                        "locales": {
+                            "type": "array",
+                            "items": {
+                                "type": "string",
+                            },
+                        },
+                    },
+                    "required": [
+                        "buildNumber",
+                        "locales",
+                    ],
+                    "additionalProperties": False,
+                },
+            },
+            "release_eta": {
+                "type": "string",
+                "default": "",
+            },
+            "release_enable_partner_repack": {
+                "type": "boolean",
+                "default": False,
+                "description": "Toggle for creating partner repacks",
+            },
+            "release_enable_partner_attribution": {
+                "type": "boolean",
+                "default": False,
+                "description": "Toggle for creating partner attribution",
+            },
+            "release_partner_build_number": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "description": (
+                    "The partner build number. This translates to, e.g. "
+                    "`v1` in the path. We generally only have to "
+                    "bump this on off-cycle partner rebuilds."
+                ),
+            },
+            "release_partners": {
+                "type": "array",
+                "description": (
+                    "A list of partners to repack, or if null or empty then use "
+                    "the current full set"
+                ),
+                "items": {
+                    "type": "string",
+                },
+            },
+            "release_partner_config": {
+                "type": "object",
+                "description": "Partner configuration to use for partner repacks.",
+                "properties": {},
+                "additionalProperties": True,
+            },
+            "release_enable_emefree": {
+                "type": "boolean",
+                "default": False,
+                "description": "Toggle for creating EME-free repacks",
+            },
+            "required_signoffs": {
+                "type": "array",
+                "description": ("The flavor of release promotion to perform."),
+                "items": {
+                    "enum": RELEASE_PROMOTION_SIGNOFFS,
+                },
+            },
+            "signoff_urls": {
+                "type": "object",
+                "default": {},
+                "additionalProperties": False,
+                "properties": get_signoff_properties(),
+            },
+        },
+        "required": ["release_promotion_flavor", "build_number"],
+    },
+)
+def release_promotion_action(parameters, graph_config, input, task_group_id, task_id):
+    release_promotion_flavor = input["release_promotion_flavor"]
+    promotion_config = graph_config["release-promotion"]["flavors"][
+        release_promotion_flavor
+    ]
+    release_history = {}
+    product = promotion_config["product"]
+
+    next_version = str(input.get("next_version") or "")
+    if promotion_config.get("version-bump", False):
+        # We force str() the input, hence the 'None'
+        if next_version in ["", "None"]:
+            raise Exception(
+                "`next_version` property needs to be provided for `{}` "
+                "target.".format(release_promotion_flavor)
+            )
+
+    if promotion_config.get("partial-updates", False):
+        partial_updates = input.get("partial_updates", {})
+        if not partial_updates and release_level(parameters["project"]) == "production":
+            raise Exception(
+                "`partial_updates` property needs to be provided for `{}`"
+                "target.".format(release_promotion_flavor)
+            )
+        balrog_prefix = product.title()
+        os.environ["PARTIAL_UPDATES"] = json.dumps(partial_updates, sort_keys=True)
+        release_history = populate_release_history(
+            balrog_prefix, parameters["project"], partial_updates=partial_updates
+        )
+
+    target_tasks_method = promotion_config["target-tasks-method"].format(
+        project=parameters["project"]
+    )
+    rebuild_kinds = input.get(
+        "rebuild_kinds", promotion_config.get("rebuild-kinds", [])
+    )
+    do_not_optimize = input.get(
+        "do_not_optimize", promotion_config.get("do-not-optimize", [])
+    )
+
+    # Make sure no pending tasks remain from a previous run
+    own_task_id = os.environ.get("TASK_ID", "")
+    try:
+        for t in list_task_group_incomplete_tasks(own_task_id):
+            if t == own_task_id:
+                continue
+            raise Exception(
+                "task group has unexpected pre-existing incomplete tasks (e.g. {})".format(
+                    t
+                )
+            )
+    except requests.exceptions.HTTPError as e:
+        # 404 means the task group doesn't exist yet, and we're fine
+        if e.response.status_code != 404:
+            raise
+
+    # Build previous_graph_ids from ``previous_graph_ids``, ``revision``,
+    # or the action parameters.
+    previous_graph_ids = input.get("previous_graph_ids")
+    if not previous_graph_ids:
+        revision = input.get("revision")
+        if revision:
+            head_rev_param = "{}head_rev".format(
+                graph_config["project-repo-param-prefix"]
+            )
+            push_parameters = {
+                head_rev_param: revision,
+                "project": parameters["project"],
+            }
+        else:
+            push_parameters = parameters
+        previous_graph_ids = [find_decision_task(push_parameters, graph_config)]
+
+    # Download parameters from the first decision task
+    parameters = get_artifact(previous_graph_ids[0], "public/parameters.yml")
+    # Download and combine full task graphs from each of the previous_graph_ids.
+    # Sometimes previous relpro action tasks will add tasks, like partials,
+    # that didn't exist in the first full_task_graph, so combining them is
+    # important. The rightmost graph should take precedence in the case of
+    # conflicts.
+    combined_full_task_graph = {}
+    for graph_id in previous_graph_ids:
+        full_task_graph = get_artifact(graph_id, "public/full-task-graph.json")
+        combined_full_task_graph.update(full_task_graph)
+    _, combined_full_task_graph = TaskGraph.from_json(combined_full_task_graph)
+    parameters["existing_tasks"] = find_existing_tasks_from_previous_kinds(
+        combined_full_task_graph, previous_graph_ids, rebuild_kinds
+    )
+    parameters["do_not_optimize"] = do_not_optimize
+    parameters["target_tasks_method"] = target_tasks_method
+    parameters["build_number"] = int(input["build_number"])
+    parameters["next_version"] = next_version
+    parameters["release_history"] = release_history
+    if promotion_config.get("is-rc"):
+        parameters["release_type"] += "-rc"
+    parameters["release_eta"] = input.get("release_eta", "")
+    parameters["release_product"] = product
+    # When doing staging releases on try, we still want to re-use tasks from
+    # previous graphs.
+    parameters["optimize_target_tasks"] = True
+
+    if release_promotion_flavor == "promote_firefox_partner_repack":
+        release_enable_partner_repack = True
+        release_enable_partner_attribution = False
+        release_enable_emefree = False
+    elif release_promotion_flavor == "promote_firefox_partner_attribution":
+        release_enable_partner_repack = False
+        release_enable_partner_attribution = True
+        release_enable_emefree = False
+    else:
+        # for promotion or ship phases, we use the action input to turn the repacks/attribution off
+        release_enable_partner_repack = input["release_enable_partner_repack"]
+        release_enable_partner_attribution = input["release_enable_partner_attribution"]
+        release_enable_emefree = input["release_enable_emefree"]
+
+    partner_url_config = get_partner_url_config(parameters, graph_config)
+    if (
+        release_enable_partner_repack
+        and not partner_url_config["release-partner-repack"]
+    ):
+        raise Exception("Can't enable partner repacks when no config url found")
+    if (
+        release_enable_partner_attribution
+        and not partner_url_config["release-partner-attribution"]
+    ):
+        raise Exception("Can't enable partner attribution when no config url found")
+    if release_enable_emefree and not partner_url_config["release-eme-free-repack"]:
+        raise Exception("Can't enable EMEfree repacks when no config url found")
+    parameters["release_enable_partner_repack"] = release_enable_partner_repack
+    parameters[
+        "release_enable_partner_attribution"
+    ] = release_enable_partner_attribution
+    parameters["release_enable_emefree"] = release_enable_emefree
+
+    partner_config = input.get("release_partner_config")
+    if not partner_config and any(
+        [
+            release_enable_partner_repack,
+            release_enable_partner_attribution,
+            release_enable_emefree,
+        ]
+    ):
+        github_token = get_token(parameters)
+        partner_config = get_partner_config(partner_url_config, github_token)
+    if partner_config:
+        parameters["release_partner_config"] = fix_partner_config(partner_config)
+    parameters["release_partners"] = input.get("release_partners")
+    if input.get("release_partner_build_number"):
+        parameters["release_partner_build_number"] = input[
+            "release_partner_build_number"
+        ]
+
+    if input["version"]:
+        parameters["version"] = input["version"]
+
+    parameters["required_signoffs"] = get_required_signoffs(input, parameters)
+    parameters["signoff_urls"] = get_signoff_urls(input, parameters)
+
+    # make parameters read-only
+    parameters = Parameters(**parameters)
+
+    taskgraph_decision({"root": graph_config.root_dir}, parameters=parameters)
diff --git a/taskcluster/gecko_taskgraph/actions/retrigger.py b/taskcluster/gecko_taskgraph/actions/retrigger.py
new file mode 100644
index 0000000000..fc8c05c83f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/retrigger.py
@@ -0,0 +1,301 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import sys
+import textwrap
+
+from taskgraph.util.taskcluster import get_task_definition, rerun_task
+
+from gecko_taskgraph.util.taskcluster import state_task
+
+from .registry import register_callback_action
+from .util import (
+    combine_task_graph_files,
+    create_task_from_def,
+    create_tasks,
+    fetch_graph_and_labels,
+    get_tasks_with_downstream,
+    relativize_datestamps,
+)
+
+logger = logging.getLogger(__name__)
+
+RERUN_STATES = ("exception", "failed")
+
+
+def _should_retrigger(task_graph, label):
+    """
+    Return whether a given task in the taskgraph should be retriggered.
+
+    This handles the case where the task isn't there by assuming it should not be.
+    """
+    if label not in task_graph:
+        logger.info(
+            "Task {} not in full taskgraph, assuming task should not be retriggered.".format(
+                label
+            )
+        )
+        return False
+    return task_graph[label].attributes.get("retrigger", False)
+
+
+@register_callback_action(
+    title="Retrigger",
+    name="retrigger",
+    symbol="rt",
+    cb_name="retrigger-decision",
+    description=textwrap.dedent(
+        """\
+        Create a clone of the task (retriggering decision, action, and cron tasks requires
+        special scopes)."""
+    ),
+    order=11,
+    context=[
+        {"kind": "decision-task"},
+        {"kind": "action-callback"},
+        {"kind": "cron-task"},
+        {"action": "backfill-task"},
+    ],
+)
+def retrigger_decision_action(parameters, graph_config, input, task_group_id, task_id):
+    """For a single task, we try to just run exactly the same task once more.
+    It's quite possible that we don't have the scopes to do so (especially for
+    an action), but this is best-effort."""
+
+    # make all of the timestamps relative; they will then be turned back into
+    # absolute timestamps relative to the current time.
+    task = get_task_definition(task_id)
+    task = relativize_datestamps(task)
+    create_task_from_def(
+        task, parameters["level"], action_tag="retrigger-decision-task"
+    )
+
+
+@register_callback_action(
+    title="Retrigger",
+    name="retrigger",
+    symbol="rt",
+    description=("Create a clone of the task."),
+    order=19,  # must be greater than other orders in this file, as this is the fallback version
+    context=[{"retrigger": "true"}],
+    schema={
+        "type": "object",
+        "properties": {
+            "downstream": {
+                "type": "boolean",
+                "description": (
+                    "If true, downstream tasks from this one will be cloned as well. "
+                    "The dependencies will be updated to work with the new task at the root."
+                ),
+                "default": False,
+            },
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 100,
+                "title": "Times",
+                "description": "How many times to run each task.",
+            },
+        },
+    },
+)
+@register_callback_action(
+    title="Retrigger (disabled)",
+    name="retrigger",
+    cb_name="retrigger-disabled",
+    symbol="rt",
+    description=(
+        "Create a clone of the task.\n\n"
+        "This type of task should typically be re-run instead of re-triggered."
+    ),
+    order=20,  # must be greater than other orders in this file, as this is the fallback version
+    context=[{}],
+    schema={
+        "type": "object",
+        "properties": {
+            "downstream": {
+                "type": "boolean",
+                "description": (
+                    "If true, downstream tasks from this one will be cloned as well. "
+                    "The dependencies will be updated to work with the new task at the root."
+                ),
+                "default": False,
+            },
+            "times": {
+                "type": "integer",
+                "default": 1,
+                "minimum": 1,
+                "maximum": 100,
+                "title": "Times",
+                "description": "How many times to run each task.",
+            },
+            "force": {
+                "type": "boolean",
+                "default": False,
+                "description": (
+                    "This task should not be re-triggered. "
+                    "This can be overridden by passing `true` here."
+                ),
+            },
+        },
+    },
+)
+def retrigger_action(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    task = get_task_definition(task_id)
+    label = task["metadata"]["name"]
+
+    with_downstream = " "
+    to_run = [label]
+
+    if not input.get("force", None) and not _should_retrigger(full_task_graph, label):
+        logger.info(
+            "Not retriggering task {}, task should not be retrigged "
+            "and force not specified.".format(label)
+        )
+        sys.exit(1)
+
+    if input.get("downstream"):
+        to_run = get_tasks_with_downstream(to_run, full_task_graph, label_to_taskid)
+        with_downstream = " (with downstream) "
+
+    times = input.get("times", 1)
+    for i in range(times):
+        create_tasks(
+            graph_config,
+            to_run,
+            full_task_graph,
+            label_to_taskid,
+            parameters,
+            decision_task_id,
+            i,
+            action_tag="retrigger-task",
+        )
+
+        logger.info(f"Scheduled {label}{with_downstream}(time {i + 1}/{times})")
+    combine_task_graph_files(list(range(times)))
+
+
+@register_callback_action(
+    title="Rerun",
+    name="rerun",
+    symbol="rr",
+    description=(
+        "Rerun a task.\n\n"
+        "This only works on failed or exception tasks in the original taskgraph,"
+        " and is CoT friendly."
+    ),
+    order=300,
+    context=[{}],
+    schema={"type": "object", "properties": {}},
+)
+def rerun_action(parameters, graph_config, input, task_group_id, task_id):
+    task = get_task_definition(task_id)
+    parameters = dict(parameters)
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    label = task["metadata"]["name"]
+    if task_id not in label_to_taskid.values():
+        logger.error(
+            "Refusing to rerun {}: taskId {} not in decision task {} label_to_taskid!".format(
+                label, task_id, decision_task_id
+            )
+        )
+
+    _rerun_task(task_id, label)
+
+
+def _rerun_task(task_id, label):
+    state = state_task(task_id)
+    if state not in RERUN_STATES:
+        logger.warning(
+            "No need to rerun {}: state '{}' not in {}!".format(
+                label, state, RERUN_STATES
+            )
+        )
+        return
+    rerun_task(task_id)
+    logger.info(f"Reran {label}")
+
+
+@register_callback_action(
+    title="Retrigger",
+    name="retrigger-multiple",
+    symbol="rt",
+    description=("Create a clone of the task."),
+    context=[],
+    schema={
+        "type": "object",
+        "properties": {
+            "requests": {
+                "type": "array",
+                "items": {
+                    "tasks": {
+                        "type": "array",
+                        "description": "An array of task labels",
+                        "items": {"type": "string"},
+                    },
+                    "times": {
+                        "type": "integer",
+                        "minimum": 1,
+                        "maximum": 100,
+                        "title": "Times",
+                        "description": "How many times to run each task.",
+                    },
+                    "additionalProperties": False,
+                },
+            },
+            "additionalProperties": False,
+        },
+    },
+)
+def retrigger_multiple(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    suffixes = []
+    for i, request in enumerate(input.get("requests", [])):
+        times = request.get("times", 1)
+        rerun_tasks = [
+            label
+            for label in request.get("tasks")
+            if not _should_retrigger(full_task_graph, label)
+        ]
+        retrigger_tasks = [
+            label
+            for label in request.get("tasks")
+            if _should_retrigger(full_task_graph, label)
+        ]
+
+        for label in rerun_tasks:
+            # XXX we should not re-run tasks pulled in from other pushes
+            # In practice, this shouldn't matter, as only completed tasks
+            # are pulled in from other pushes and treeherder won't pass
+            # those labels.
+            _rerun_task(label_to_taskid[label], label)
+
+        for j in range(times):
+            suffix = f"{i}-{j}"
+            suffixes.append(suffix)
+            create_tasks(
+                graph_config,
+                retrigger_tasks,
+                full_task_graph,
+                label_to_taskid,
+                parameters,
+                decision_task_id,
+                suffix,
+                action_tag="retrigger-multiple-task",
+            )
+
+    if suffixes:
+        combine_task_graph_files(suffixes)
diff --git a/taskcluster/gecko_taskgraph/actions/retrigger_custom.py b/taskcluster/gecko_taskgraph/actions/retrigger_custom.py
new file mode 100644
index 0000000000..677cb00a11
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/retrigger_custom.py
@@ -0,0 +1,185 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+
+from taskgraph.util.parameterization import resolve_task_references
+from taskgraph.util.taskcluster import get_task_definition
+
+from .registry import register_callback_action
+from .util import create_task_from_def, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+# Properties available for custom retrigger of any supported test suites
+basic_properties = {
+    "path": {
+        "type": "string",
+        "maxLength": 255,
+        "default": "",
+        "title": "Path name",
+        "description": "Path of test(s) to retrigger",
+    },
+    "logLevel": {
+        "type": "string",
+        "enum": ["debug", "info", "warning", "error", "critical"],
+        "default": "info",
+        "title": "Log level",
+        "description": "Log level for output (INFO is normal, DEBUG gives more detail)",
+    },
+    "environment": {
+        "type": "object",
+        "default": {"MOZ_LOG": ""},
+        "title": "Extra environment variables",
+        "description": "Extra environment variables to use for this run",
+        "additionalProperties": {"type": "string"},
+    },
+}
+
+# Additional properties available for custom retrigger of some additional test suites
+extended_properties = basic_properties.copy()
+extended_properties.update(
+    {
+        "runUntilFail": {
+            "type": "boolean",
+            "default": False,
+            "title": "Run until failure",
+            "description": (
+                "Runs the specified set of tests repeatedly "
+                "until failure (up to REPEAT times)"
+            ),
+        },
+        "repeat": {
+            "type": "integer",
+            "default": 0,
+            "minimum": 0,
+            "title": "Repeat test(s) N times",
+            "description": (
+                "Run test(s) repeatedly (usually used in "
+                "conjunction with runUntilFail)"
+            ),
+        },
+        "preferences": {
+            "type": "object",
+            "default": {"remote.log.level": "Info"},
+            "title": "Extra gecko (about:config) preferences",
+            "description": "Extra gecko (about:config) preferences to use for this run",
+            "additionalProperties": {"type": "string"},
+        },
+    }
+)
+
+
+@register_callback_action(
+    name="retrigger-custom",
+    title="Retrigger task with custom parameters",
+    symbol="rt",
+    description="Retriggers the specified task with custom environment and parameters",
+    context=[
+        {"test-type": "mochitest", "worker-implementation": "docker-worker"},
+        {"test-type": "reftest", "worker-implementation": "docker-worker"},
+        {"test-type": "geckoview-junit", "worker-implementation": "docker-worker"},
+    ],
+    order=10,
+    schema={
+        "type": "object",
+        "properties": extended_properties,
+        "additionalProperties": False,
+        "required": ["path"],
+    },
+)
+def extended_custom_retrigger_action(
+    parameters, graph_config, input, task_group_id, task_id
+):
+    handle_custom_retrigger(parameters, graph_config, input, task_group_id, task_id)
+
+
+@register_callback_action(
+    name="retrigger-custom (gtest)",
+    title="Retrigger gtest task with custom parameters",
+    symbol="rt",
+    description="Retriggers the specified task with custom environment and parameters",
+    context=[{"test-type": "gtest", "worker-implementation": "docker-worker"}],
+    order=10,
+    schema={
+        "type": "object",
+        "properties": basic_properties,
+        "additionalProperties": False,
+        "required": ["path"],
+    },
+)
+def basic_custom_retrigger_action_basic(
+    parameters, graph_config, input, task_group_id, task_id
+):
+    handle_custom_retrigger(parameters, graph_config, input, task_group_id, task_id)
+
+
+def handle_custom_retrigger(parameters, graph_config, input, task_group_id, task_id):
+    task = get_task_definition(task_id)
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+
+    pre_task = full_task_graph.tasks[task["metadata"]["name"]]
+
+    # fix up the task's dependencies, similar to how optimization would
+    # have done in the decision
+    dependencies = {
+        name: label_to_taskid[label] for name, label in pre_task.dependencies.items()
+    }
+    new_task_definition = resolve_task_references(
+        pre_task.label, pre_task.task, task_id, decision_task_id, dependencies
+    )
+    new_task_definition.setdefault("dependencies", []).extend(dependencies.values())
+
+    # don't want to run mozharness tests, want a custom mach command instead
+    new_task_definition["payload"]["command"] += ["--no-run-tests"]
+
+    custom_mach_command = [task["tags"]["test-type"]]
+
+    # mochitests may specify a flavor
+    if new_task_definition["payload"]["env"].get("MOCHITEST_FLAVOR"):
+        custom_mach_command += [
+            "--keep-open=false",
+            "-f",
+            new_task_definition["payload"]["env"]["MOCHITEST_FLAVOR"],
+        ]
+
+    enable_e10s = json.loads(
+        new_task_definition["payload"]["env"].get("ENABLE_E10S", "true")
+    )
+    if not enable_e10s:
+        custom_mach_command += ["--disable-e10s"]
+
+    custom_mach_command += [
+        "--log-tbpl=-",
+        "--log-tbpl-level={}".format(input.get("logLevel", "debug")),
+    ]
+    if input.get("runUntilFail"):
+        custom_mach_command += ["--run-until-failure"]
+    if input.get("repeat"):
+        custom_mach_command += ["--repeat", str(input.get("repeat", 30))]
+
+    # add any custom gecko preferences
+    for (key, val) in input.get("preferences", {}).items():
+        custom_mach_command += ["--setpref", f"{key}={val}"]
+
+    custom_mach_command += [input["path"]]
+    new_task_definition["payload"]["env"]["CUSTOM_MACH_COMMAND"] = " ".join(
+        custom_mach_command
+    )
+
+    # update environment
+    new_task_definition["payload"]["env"].update(input.get("environment", {}))
+
+    # tweak the treeherder symbol
+    new_task_definition["extra"]["treeherder"]["symbol"] += "-custom"
+
+    logging.info("New task definition: %s", new_task_definition)
+
+    create_task_from_def(
+        new_task_definition, parameters["level"], action_tag="retrigger-custom-task"
+    )
diff --git a/taskcluster/gecko_taskgraph/actions/run_missing_tests.py b/taskcluster/gecko_taskgraph/actions/run_missing_tests.py
new file mode 100644
index 0000000000..92310445f3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/run_missing_tests.py
@@ -0,0 +1,62 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from taskgraph.util.taskcluster import get_artifact
+
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels
+
+logger = logging.getLogger(__name__)
+
+
+@register_callback_action(
+    name="run-missing-tests",
+    title="Run Missing Tests",
+    symbol="rmt",
+    description=(
+        "Run tests in the selected push that were optimized away, usually by SETA."
+        "\n"
+        "This action is for use on pushes that will be merged into another branch,"
+        "to check that optimization hasn't hidden any failures."
+    ),
+    order=250,
+    context=[],  # Applies to decision task
+)
+def run_missing_tests(parameters, graph_config, input, task_group_id, task_id):
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    target_tasks = get_artifact(decision_task_id, "public/target-tasks.json")
+
+    # The idea here is to schedule all tasks of the `test` kind that were
+    # targetted but did not appear in the final task-graph -- those were the
+    # optimized tasks.
+    to_run = []
+    already_run = 0
+    for label in target_tasks:
+        task = full_task_graph.tasks[label]
+        if task.kind != "test":
+            continue  # not a test
+        if label in label_to_taskid:
+            already_run += 1
+            continue
+        to_run.append(label)
+
+    create_tasks(
+        graph_config,
+        to_run,
+        full_task_graph,
+        label_to_taskid,
+        parameters,
+        decision_task_id,
+    )
+
+    logger.info(
+        "Out of {} test tasks, {} already existed and the action created {}".format(
+            already_run + len(to_run), already_run, len(to_run)
+        )
+    )
diff --git a/taskcluster/gecko_taskgraph/actions/scriptworker_canary.py b/taskcluster/gecko_taskgraph/actions/scriptworker_canary.py
new file mode 100644
index 0000000000..e0057da9a6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/scriptworker_canary.py
@@ -0,0 +1,45 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.parameters import Parameters
+
+from gecko_taskgraph.actions.registry import register_callback_action
+from gecko_taskgraph.decision import taskgraph_decision
+
+
+@register_callback_action(
+    title="Push scriptworker canaries.",
+    name="scriptworker-canary",
+    symbol="scriptworker-canary",
+    description="Trigger scriptworker-canary pushes for the given scriptworkers.",
+    schema={
+        "type": "object",
+        "properties": {
+            "scriptworkers": {
+                "type": "array",
+                "description": "List of scriptworker types to run canaries for.",
+                "items": {"type": "string"},
+            },
+        },
+    },
+    order=1000,
+    permission="scriptworker-canary",
+    context=[],
+)
+def scriptworker_canary(parameters, graph_config, input, task_group_id, task_id):
+    scriptworkers = input["scriptworkers"]
+
+    # make parameters read-write
+    parameters = dict(parameters)
+
+    parameters["target_tasks_method"] = "scriptworker_canary"
+    parameters["try_task_config"] = {
+        "scriptworker-canary-workers": scriptworkers,
+    }
+    parameters["tasks_for"] = "action"
+
+    # make parameters read-only
+    parameters = Parameters(**parameters)
+
+    taskgraph_decision({"root": graph_config.root_dir}, parameters=parameters)
diff --git a/taskcluster/gecko_taskgraph/actions/side_by_side.py b/taskcluster/gecko_taskgraph/actions/side_by_side.py
new file mode 100644
index 0000000000..816e716fde
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/side_by_side.py
@@ -0,0 +1,189 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import os
+import sys
+from functools import partial
+
+from taskgraph.util.taskcluster import get_artifact, get_task_definition
+
+from ..util.taskcluster import list_task_group_complete_tasks
+from .registry import register_callback_action
+from .util import create_tasks, fetch_graph_and_labels, get_decision_task_id, get_pushes
+
+logger = logging.getLogger(__name__)
+
+
+def input_for_support_action(revision, base_revision, base_branch, task):
+    """Generate input for action to be scheduled.
+
+    Define what label to schedule with 'label'.
+    If it is a test task that uses explicit manifests add that information.
+    """
+    platform, test_name = task["metadata"]["name"].split("/opt-")
+    new_branch = os.environ.get("GECKO_HEAD_REPOSITORY", "/try").split("/")[-1]
+    symbol = task["extra"]["treeherder"]["symbol"]
+    input = {
+        "label": "perftest-linux-side-by-side",
+        "symbol": symbol,
+        "new_revision": revision,
+        "base_revision": base_revision,
+        "test_name": test_name,
+        "platform": platform,
+        "base_branch": base_branch,
+        "new_branch": new_branch,
+    }
+
+    return input
+
+
+def side_by_side_modifier(task, input):
+    if task.label != input["label"]:
+        return task
+
+    # Make side-by-side job searchable by the platform, test name, and revisions
+    # it was triggered for
+    task.task["metadata"][
+        "name"
+    ] = f"{input['platform']} {input['test_name']} {input['base_revision'][:12]} {input['new_revision'][:12]}"
+    # Use a job symbol to include the symbol of the job the side-by-side
+    # is running for
+    task.task["extra"]["treeherder"]["symbol"] += f"-{input['symbol']}"
+
+    cmd = task.task["payload"]["command"]
+    task.task["payload"]["command"][1][-1] = cmd[1][-1].format(**input)
+
+    return task
+
+
+@register_callback_action(
+    title="Side by side",
+    name="side-by-side",
+    symbol="gen-sxs",
+    description=(
+        "Given a performance test pageload job generate a side-by-side comparison against"
+        "the pageload job from the revision at the input."
+    ),
+    order=200,
+    context=[{"test-type": "raptor"}],
+    schema={
+        "type": "object",
+        "properties": {
+            "revision": {
+                "type": "string",
+                "default": "",
+                "description": "Revision of the push against the comparison is wanted.",
+            },
+            "project": {
+                "type": "string",
+                "default": "autoland",
+                "description": "Revision of the push against the comparison is wanted.",
+            },
+        },
+        "additionalProperties": False,
+    },
+)
+def side_by_side_action(parameters, graph_config, input, task_group_id, task_id):
+    """
+    This action does a side-by-side comparison between current revision and
+    the revision entered manually or the latest revision that ran the
+    pageload job (via support action).
+
+    To execute this action locally follow the documentation here:
+    https://firefox-source-docs.mozilla.org/taskcluster/actions.html#testing-the-action-locally
+    """
+    task = get_task_definition(task_id)
+    decision_task_id, full_task_graph, label_to_taskid = fetch_graph_and_labels(
+        parameters, graph_config
+    )
+    # TODO: find another way to detect side-by-side comparable jobs
+    # (potentially lookig at the visual metrics flag)
+    if not (
+        "browsertime-tp6" in task["metadata"]["name"]
+        or "welcome" in task["metadata"]["name"]
+    ):
+        logger.exception(
+            f"Task {task['metadata']['name']} is not side-by-side comparable."
+        )
+        return
+
+    failed = False
+    input_for_action = {}
+
+    if input.get("revision"):
+        # If base_revision was introduced manually, use that
+        input_for_action = input_for_support_action(
+            revision=parameters["head_rev"],
+            base_revision=input.get("revision"),
+            base_branch=input.get("project"),
+            task=task,
+        )
+    else:
+        current_push_id = int(parameters["pushlog_id"]) - 1
+        # Go decrementally through pushlog_id, get push data, decision task id,
+        # full task graph and everything needed to find which of the past revisions
+        # ran the pageload job to compare against
+        while int(parameters["pushlog_id"]) - current_push_id < 30:
+            pushes = get_pushes(
+                project=parameters["head_repository"],
+                end_id=current_push_id,
+                depth=1,
+                full_response=True,
+            )
+            try:
+                # Get label-to-taskid.json artifact + the tasks triggered
+                # by the action tasks at a later time than the decision task
+                current_decision_task_id = get_decision_task_id(
+                    parameters["project"], current_push_id
+                )
+                current_task_group_id = get_task_definition(current_decision_task_id)[
+                    "taskGroupId"
+                ]
+                current_label_to_taskid = get_artifact(
+                    current_decision_task_id, "public/label-to-taskid.json"
+                )
+                current_full_label_to_taskid = current_label_to_taskid.copy()
+                action_task_triggered = list_task_group_complete_tasks(
+                    current_task_group_id
+                )
+                current_full_label_to_taskid.update(action_task_triggered)
+                if task["metadata"]["name"] in current_full_label_to_taskid.keys():
+                    input_for_action = input_for_support_action(
+                        revision=parameters["head_rev"],
+                        base_revision=pushes[str(current_push_id)]["changesets"][-1],
+                        base_branch=input.get("project", parameters["project"]),
+                        task=task,
+                    )
+                    break
+            except Exception:
+                logger.warning(
+                    f"Could not find decision task for push {current_push_id}"
+                )
+                # The decision task may have failed, this is common enough that we
+                # don't want to report an error for it.
+                continue
+            current_push_id -= 1
+        if not input_for_action:
+            raise Exception(
+                "Could not find a side-by-side comparable task within a depth of 30 revisions."
+            )
+
+    try:
+        create_tasks(
+            graph_config,
+            [input_for_action["label"]],
+            full_task_graph,
+            label_to_taskid,
+            parameters,
+            decision_task_id,
+            modifier=partial(side_by_side_modifier, input=input_for_action),
+        )
+    except Exception as e:
+        logger.exception(f"Failed to trigger action: {e}.")
+        failed = True
+
+    if failed:
+        sys.exit(1)
diff --git a/taskcluster/gecko_taskgraph/actions/util.py b/taskcluster/gecko_taskgraph/actions/util.py
new file mode 100644
index 0000000000..76181dae2b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/actions/util.py
@@ -0,0 +1,433 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import concurrent.futures as futures
+import copy
+import logging
+import os
+import re
+from functools import reduce
+
+import jsone
+import requests
+from requests.exceptions import HTTPError
+from slugid import nice as slugid
+from taskgraph import create
+from taskgraph.optimize.base import optimize_task_graph
+from taskgraph.taskgraph import TaskGraph
+from taskgraph.util.taskcluster import (
+    CONCURRENCY,
+    find_task_id,
+    get_artifact,
+    get_session,
+    get_task_definition,
+    list_tasks,
+    parse_time,
+)
+
+from gecko_taskgraph.decision import read_artifact, rename_artifact, write_artifact
+from gecko_taskgraph.util.taskcluster import trigger_hook
+from gecko_taskgraph.util.taskgraph import find_decision_task
+
+logger = logging.getLogger(__name__)
+
+INDEX_TMPL = "gecko.v2.{}.pushlog-id.{}.decision"
+PUSHLOG_TMPL = "{}/json-pushes?version=2&startID={}&endID={}"
+
+
+def _tags_within_context(tags, context=[]):
+    """A context of [] means that it *only* applies to a task group"""
+    return any(
+        all(tag in tags and tags[tag] == tag_set[tag] for tag in tag_set.keys())
+        for tag_set in context
+    )
+
+
+def _extract_applicable_action(actions_json, action_name, task_group_id, task_id):
+    """Extract action that applies to the given task or task group.
+
+    A task (as defined by its tags) is said to match a tag-set if its
+    tags are a super-set of the tag-set. A tag-set is a set of key-value pairs.
+
+    An action (as defined by its context) is said to be relevant for
+    a given task, if the task's tags match one of the tag-sets given
+    in the context property of the action.
+
+    The order of the actions is significant. When multiple actions apply to a
+    task the first one takes precedence.
+
+    For more details visit:
+    https://docs.taskcluster.net/docs/manual/design/conventions/actions/spec
+    """
+    if task_id:
+        tags = get_task_definition(task_id).get("tags")
+
+    for _action in actions_json["actions"]:
+        if action_name != _action["name"]:
+            continue
+
+        context = _action.get("context", [])
+        # Ensure the task is within the context of the action
+        if task_id and tags and _tags_within_context(tags, context):
+            return _action
+        if context == []:
+            return _action
+
+    available_actions = ", ".join(sorted({a["name"] for a in actions_json["actions"]}))
+    raise LookupError(
+        "{} action is not available for this task. Available: {}".format(
+            action_name, available_actions
+        )
+    )
+
+
+def trigger_action(action_name, decision_task_id, task_id=None, input={}):
+    if not decision_task_id:
+        raise ValueError("No decision task. We can't find the actions artifact.")
+    actions_json = get_artifact(decision_task_id, "public/actions.json")
+    if actions_json["version"] != 1:
+        raise RuntimeError("Wrong version of actions.json, unable to continue")
+
+    # These values substitute $eval in the template
+    context = {
+        "input": input,
+        "taskId": task_id,
+        "taskGroupId": decision_task_id,
+    }
+    # https://docs.taskcluster.net/docs/manual/design/conventions/actions/spec#variables
+    context.update(actions_json["variables"])
+    action = _extract_applicable_action(
+        actions_json, action_name, decision_task_id, task_id
+    )
+    kind = action["kind"]
+    if create.testing:
+        logger.info(f"Skipped triggering action for {kind} as testing is enabled")
+    elif kind == "hook":
+        hook_payload = jsone.render(action["hookPayload"], context)
+        trigger_hook(action["hookGroupId"], action["hookId"], hook_payload)
+    else:
+        raise NotImplementedError(f"Unable to submit actions with {kind} kind.")
+
+
+def get_pushes_from_params_input(parameters, input):
+    inclusive_tweak = 1 if input.get("inclusive") else 0
+    return get_pushes(
+        project=parameters["head_repository"],
+        end_id=int(parameters["pushlog_id"]) - (1 - inclusive_tweak),
+        depth=input.get("depth", 9) + inclusive_tweak,
+    )
+
+
+def get_pushes(project, end_id, depth, full_response=False):
+    pushes = []
+    while True:
+        start_id = max(end_id - depth, 0)
+        pushlog_url = PUSHLOG_TMPL.format(project, start_id, end_id)
+        logger.debug(pushlog_url)
+        r = requests.get(pushlog_url)
+        r.raise_for_status()
+        pushes = pushes + list(r.json()["pushes"].keys())
+        if len(pushes) >= depth:
+            break
+
+        end_id = start_id - 1
+        start_id -= depth
+        if start_id < 0:
+            break
+
+    pushes = sorted(pushes)[-depth:]
+    push_dict = {push: r.json()["pushes"][push] for push in pushes}
+    return push_dict if full_response else pushes
+
+
+def get_decision_task_id(project, push_id):
+    return find_task_id(INDEX_TMPL.format(project, push_id))
+
+
+def get_parameters(decision_task_id):
+    return get_artifact(decision_task_id, "public/parameters.yml")
+
+
+def get_tasks_with_downstream(labels, full_task_graph, label_to_taskid):
+    # Used to gather tasks when downstream tasks need to run as well
+    return full_task_graph.graph.transitive_closure(
+        set(labels), reverse=True
+    ).nodes & set(label_to_taskid.keys())
+
+
+def fetch_graph_and_labels(parameters, graph_config):
+    decision_task_id = find_decision_task(parameters, graph_config)
+
+    # First grab the graph and labels generated during the initial decision task
+    full_task_graph = get_artifact(decision_task_id, "public/full-task-graph.json")
+    logger.info("Load taskgraph from JSON.")
+    _, full_task_graph = TaskGraph.from_json(full_task_graph)
+    label_to_taskid = get_artifact(decision_task_id, "public/label-to-taskid.json")
+
+    logger.info("Fetching additional tasks from action and cron tasks.")
+    # fetch everything in parallel; this avoids serializing any delay in downloading
+    # each artifact (such as waiting for the artifact to be mirrored locally)
+    with futures.ThreadPoolExecutor(CONCURRENCY) as e:
+        fetches = []
+
+        # fetch any modifications made by action tasks and swap out new tasks
+        # for old ones
+        def fetch_action(task_id):
+            logger.info(f"fetching label-to-taskid.json for action task {task_id}")
+            try:
+                run_label_to_id = get_artifact(task_id, "public/label-to-taskid.json")
+                label_to_taskid.update(run_label_to_id)
+            except HTTPError as e:
+                if e.response.status_code != 404:
+                    raise
+                logger.debug(f"No label-to-taskid.json found for {task_id}: {e}")
+
+        head_rev_param = "{}head_rev".format(graph_config["project-repo-param-prefix"])
+
+        namespace = "{}.v2.{}.revision.{}.taskgraph.actions".format(
+            graph_config["trust-domain"],
+            parameters["project"],
+            parameters[head_rev_param],
+        )
+        for task_id in list_tasks(namespace):
+            fetches.append(e.submit(fetch_action, task_id))
+
+        # Similarly for cron tasks..
+        def fetch_cron(task_id):
+            logger.info(f"fetching label-to-taskid.json for cron task {task_id}")
+            try:
+                run_label_to_id = get_artifact(task_id, "public/label-to-taskid.json")
+                label_to_taskid.update(run_label_to_id)
+            except HTTPError as e:
+                if e.response.status_code != 404:
+                    raise
+                logger.debug(f"No label-to-taskid.json found for {task_id}: {e}")
+
+        namespace = "{}.v2.{}.revision.{}.cron".format(
+            graph_config["trust-domain"],
+            parameters["project"],
+            parameters[head_rev_param],
+        )
+        for task_id in list_tasks(namespace):
+            fetches.append(e.submit(fetch_cron, task_id))
+
+        # now wait for each fetch to complete, raising an exception if there
+        # were any issues
+        for f in futures.as_completed(fetches):
+            f.result()
+
+    return (decision_task_id, full_task_graph, label_to_taskid)
+
+
+def create_task_from_def(task_def, level, action_tag=None):
+    """Create a new task from a definition rather than from a label
+    that is already in the full-task-graph. The task definition will
+    have {relative-datestamp': '..'} rendered just like in a decision task.
+    Use this for entirely new tasks or ones that change internals of the task.
+    It is useful if you want to "edit" the full_task_graph and then hand
+    it to this function. No dependencies will be scheduled. You must handle
+    this yourself. Seeing how create_tasks handles it might prove helpful."""
+    task_def["schedulerId"] = f"gecko-level-{level}"
+    label = task_def["metadata"]["name"]
+    task_id = slugid()
+    session = get_session()
+    if action_tag:
+        task_def.setdefault("tags", {}).setdefault("action", action_tag)
+    create.create_task(session, task_id, label, task_def)
+
+
+def update_parent(task, graph):
+    task.task.setdefault("extra", {})["parent"] = os.environ.get("TASK_ID", "")
+    return task
+
+
+def update_action_tag(task, graph, action_tag):
+    task.task.setdefault("tags", {}).setdefault("action", action_tag)
+    return task
+
+
+def update_dependencies(task, graph):
+    if os.environ.get("TASK_ID"):
+        task.task.setdefault("dependencies", []).append(os.environ["TASK_ID"])
+    return task
+
+
+def create_tasks(
+    graph_config,
+    to_run,
+    full_task_graph,
+    label_to_taskid,
+    params,
+    decision_task_id,
+    suffix="",
+    modifier=lambda t: t,
+    action_tag=None,
+):
+    """Create new tasks.  The task definition will have {relative-datestamp':
+    '..'} rendered just like in a decision task.  Action callbacks should use
+    this function to create new tasks,
+    allowing easy debugging with `mach taskgraph action-callback --test`.
+    This builds up all required tasks to run in order to run the tasks requested.
+
+    Optionally this function takes a `modifier` function that is passed in each
+    task before it is put into a new graph. It should return a valid task. Note
+    that this is passed _all_ tasks in the graph, not just the set in to_run. You
+    may want to skip modifying tasks not in your to_run list.
+
+    If `suffix` is given, then it is used to give unique names to the resulting
+    artifacts.  If you call this function multiple times in the same action,
+    pass a different suffix each time to avoid overwriting artifacts.
+
+    If you wish to create the tasks in a new group, leave out decision_task_id.
+
+    Returns an updated label_to_taskid containing the new tasks"""
+    import gecko_taskgraph.optimize  # noqa: triggers registration of strategies
+
+    if suffix != "":
+        suffix = f"-{suffix}"
+    to_run = set(to_run)
+
+    #  Copy to avoid side-effects later
+    full_task_graph = copy.deepcopy(full_task_graph)
+    label_to_taskid = label_to_taskid.copy()
+
+    target_graph = full_task_graph.graph.transitive_closure(to_run)
+    target_task_graph = TaskGraph(
+        {l: modifier(full_task_graph[l]) for l in target_graph.nodes}, target_graph
+    )
+    target_task_graph.for_each_task(update_parent)
+    if action_tag:
+        target_task_graph.for_each_task(update_action_tag, action_tag)
+    if decision_task_id and decision_task_id != os.environ.get("TASK_ID"):
+        target_task_graph.for_each_task(update_dependencies)
+    optimized_task_graph, label_to_taskid = optimize_task_graph(
+        target_task_graph,
+        to_run,
+        params,
+        to_run,
+        decision_task_id,
+        existing_tasks=label_to_taskid,
+    )
+    write_artifact(f"task-graph{suffix}.json", optimized_task_graph.to_json())
+    write_artifact(f"label-to-taskid{suffix}.json", label_to_taskid)
+    write_artifact(f"to-run{suffix}.json", list(to_run))
+    create.create_tasks(
+        graph_config,
+        optimized_task_graph,
+        label_to_taskid,
+        params,
+        decision_task_id,
+    )
+    return label_to_taskid
+
+
+def _update_reducer(accumulator, new_value):
+    "similar to set or dict `update` method, but returning the modified object"
+    accumulator.update(new_value)
+    return accumulator
+
+
+def combine_task_graph_files(suffixes):
+    """Combine task-graph-{suffix}.json files into a single task-graph.json file.
+
+    Since Chain of Trust verification requires a task-graph.json file that
+    contains all children tasks, we can combine the various task-graph-0.json
+    type files into a master task-graph.json file at the end.
+
+    Actions also look for various artifacts, so we combine those in a similar
+    fashion.
+
+    In the case where there is only one suffix, we simply rename it to avoid the
+    additional cost of uploading two copies of the same data.
+    """
+
+    if len(suffixes) == 1:
+        for filename in ["task-graph", "label-to-taskid", "to-run"]:
+            rename_artifact(f"{filename}-{suffixes[0]}.json", f"{filename}.json")
+        return
+
+    def combine(file_contents, base):
+        return reduce(_update_reducer, file_contents, base)
+
+    files = [read_artifact(f"task-graph-{suffix}.json") for suffix in suffixes]
+    write_artifact("task-graph.json", combine(files, dict()))
+
+    files = [read_artifact(f"label-to-taskid-{suffix}.json") for suffix in suffixes]
+    write_artifact("label-to-taskid.json", combine(files, dict()))
+
+    files = [read_artifact(f"to-run-{suffix}.json") for suffix in suffixes]
+    write_artifact("to-run.json", list(combine(files, set())))
+
+
+def relativize_datestamps(task_def):
+    """
+    Given a task definition as received from the queue, convert all datestamps
+    to {relative_datestamp: ..} format, with the task creation time as "now".
+    The result is useful for handing to ``create_task``.
+    """
+    base = parse_time(task_def["created"])
+    # borrowed from https://github.com/epoberezkin/ajv/blob/master/lib/compile/formats.js
+    ts_pattern = re.compile(
+        r"^\d\d\d\d-[0-1]\d-[0-3]\d[t\s]"
+        r"(?:[0-2]\d:[0-5]\d:[0-5]\d|23:59:60)(?:\.\d+)?"
+        r"(?:z|[+-]\d\d:\d\d)$",
+        re.I,
+    )
+
+    def recurse(value):
+        if isinstance(value, str):
+            if ts_pattern.match(value):
+                value = parse_time(value)
+                diff = value - base
+                return {"relative-datestamp": f"{int(diff.total_seconds())} seconds"}
+        if isinstance(value, list):
+            return [recurse(e) for e in value]
+        if isinstance(value, dict):
+            return {k: recurse(v) for k, v in value.items()}
+        return value
+
+    return recurse(task_def)
+
+
+def add_args_to_command(cmd_parts, extra_args=[]):
+    """
+    Add custom command line args to a given command.
+    args:
+      cmd_parts: the raw command as seen by taskcluster
+      extra_args: array of args we want to add
+    """
+    # Prevent modification of the caller's copy of cmd_parts
+    cmd_parts = copy.deepcopy(cmd_parts)
+    cmd_type = "default"
+    if len(cmd_parts) == 1 and isinstance(cmd_parts[0], dict):
+        # windows has single cmd part as dict: 'task-reference', with long string
+        cmd_parts = cmd_parts[0]["task-reference"].split(" ")
+        cmd_type = "dict"
+    elif len(cmd_parts) == 1 and isinstance(cmd_parts[0], str):
+        # windows has single cmd part as a long string
+        cmd_parts = cmd_parts[0].split(" ")
+        cmd_type = "unicode"
+    elif len(cmd_parts) == 1 and isinstance(cmd_parts[0], list):
+        # osx has an single value array with an array inside
+        cmd_parts = cmd_parts[0]
+        cmd_type = "subarray"
+    elif len(cmd_parts) == 2 and isinstance(cmd_parts[1], list):
+        # osx has an double value array with an array inside each element.
+        # The first element is a pre-requisite command while the second
+        # is the actual test command.
+        cmd_type = "subarray2"
+
+    if cmd_type == "subarray2":
+        cmd_parts[1].extend(extra_args)
+    else:
+        cmd_parts.extend(extra_args)
+
+    if cmd_type == "dict":
+        cmd_parts = [{"task-reference": " ".join(cmd_parts)}]
+    elif cmd_type == "unicode":
+        cmd_parts = [" ".join(cmd_parts)]
+    elif cmd_type == "subarray":
+        cmd_parts = [cmd_parts]
+    return cmd_parts
diff --git a/taskcluster/gecko_taskgraph/config.py b/taskcluster/gecko_taskgraph/config.py
new file mode 100644
index 0000000000..62c261647a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/config.py
@@ -0,0 +1,122 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.util.schema import Schema, optionally_keyed_by
+from voluptuous import Any, Optional, Required
+
+graph_config_schema = Schema(
+    {
+        # The trust-domain for this graph.
+        # (See https://firefox-source-docs.mozilla.org/taskcluster/taskcluster/taskgraph.html#taskgraph-trust-domain)  # noqa
+        Required("trust-domain"): str,
+        # This specifes the prefix for repo parameters that refer to the project being built.
+        # This selects between `head_rev` and `comm_head_rev` and related paramters.
+        # (See http://firefox-source-docs.mozilla.org/taskcluster/taskcluster/parameters.html#push-information  # noqa
+        # and http://firefox-source-docs.mozilla.org/taskcluster/taskcluster/parameters.html#comm-push-information)  # noqa
+        Required("project-repo-param-prefix"): str,
+        # This specifies the top level directory of the application being built.
+        # ie. "browser/" for Firefox, "comm/mail/" for Thunderbird.
+        Required("product-dir"): str,
+        Required("treeherder"): {
+            # Mapping of treeherder group symbols to descriptive names
+            Required("group-names"): {str: str}
+        },
+        Required("index"): {Required("products"): [str]},
+        Required("try"): {
+            # We have a few platforms for which we want to do some "extra" builds, or at
+            # least build-ish things.  Sort of.  Anyway, these other things are implemented
+            # as different "platforms".  These do *not* automatically ride along with "-p
+            # all"
+            Required("ridealong-builds"): {str: [str]},
+        },
+        Required("release-promotion"): {
+            Required("products"): [str],
+            Required("flavors"): {
+                str: {
+                    Required("product"): str,
+                    Required("target-tasks-method"): str,
+                    Optional("is-rc"): bool,
+                    Optional("rebuild-kinds"): [str],
+                    Optional("version-bump"): bool,
+                    Optional("partial-updates"): bool,
+                }
+            },
+        },
+        Required("merge-automation"): {
+            Required("behaviors"): {
+                str: {
+                    Optional("from-branch"): str,
+                    Required("to-branch"): str,
+                    Optional("from-repo"): str,
+                    Required("to-repo"): str,
+                    Required("version-files"): [
+                        {
+                            Required("filename"): str,
+                            Optional("new-suffix"): str,
+                            Optional("version-bump"): Any("major", "minor"),
+                        }
+                    ],
+                    Required("replacements"): [[str]],
+                    Required("merge-old-head"): bool,
+                    Optional("base-tag"): str,
+                    Optional("end-tag"): str,
+                    Optional("fetch-version-from"): str,
+                }
+            },
+        },
+        Required("scriptworker"): {
+            # Prefix to add to scopes controlling scriptworkers
+            Required("scope-prefix"): str,
+        },
+        Required("task-priority"): optionally_keyed_by(
+            "project",
+            Any(
+                "highest",
+                "very-high",
+                "high",
+                "medium",
+                "low",
+                "very-low",
+                "lowest",
+            ),
+        ),
+        Required("partner-urls"): {
+            Required("release-partner-repack"): optionally_keyed_by(
+                "release-product", "release-level", "release-type", Any(str, None)
+            ),
+            Optional("release-partner-attribution"): optionally_keyed_by(
+                "release-product", "release-level", "release-type", Any(str, None)
+            ),
+            Required("release-eme-free-repack"): optionally_keyed_by(
+                "release-product", "release-level", "release-type", Any(str, None)
+            ),
+        },
+        Required("workers"): {
+            Required("aliases"): {
+                str: {
+                    Required("provisioner"): optionally_keyed_by("level", str),
+                    Required("implementation"): str,
+                    Required("os"): str,
+                    Required("worker-type"): optionally_keyed_by(
+                        "level", "release-level", "project", str
+                    ),
+                }
+            },
+        },
+        Required("mac-notarization"): {
+            Required("mac-entitlements"): optionally_keyed_by(
+                "platform", "release-level", str
+            ),
+            Required("mac-requirements"): optionally_keyed_by("platform", str),
+        },
+        Required("taskgraph"): {
+            Optional(
+                "register",
+                description="Python function to call to register extensions.",
+            ): str,
+            Optional("decision-parameters"): str,
+        },
+        Required("expiration-policy"): optionally_keyed_by("project", {str: str}),
+    }
+)
diff --git a/taskcluster/gecko_taskgraph/decision.py b/taskcluster/gecko_taskgraph/decision.py
new file mode 100644
index 0000000000..1849770481
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/decision.py
@@ -0,0 +1,565 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+import os
+import shutil
+import sys
+import time
+from collections import defaultdict
+
+import yaml
+from redo import retry
+from taskgraph import create
+from taskgraph.create import create_tasks
+
+# TODO: Let standalone taskgraph generate parameters instead of calling internals
+from taskgraph.decision import (
+    _determine_more_accurate_base_ref,
+    _determine_more_accurate_base_rev,
+    _get_env_prefix,
+)
+from taskgraph.generator import TaskGraphGenerator
+from taskgraph.parameters import Parameters
+from taskgraph.taskgraph import TaskGraph
+from taskgraph.util.python_path import find_object
+from taskgraph.util.schema import Schema, validate_schema
+from taskgraph.util.taskcluster import get_artifact
+from taskgraph.util.vcs import get_repository
+from taskgraph.util.yaml import load_yaml
+from voluptuous import Any, Optional, Required
+
+from . import GECKO
+from .actions import render_actions_json
+from .parameters import get_app_version, get_version
+from .try_option_syntax import parse_message
+from .util.backstop import BACKSTOP_INDEX, is_backstop
+from .util.bugbug import push_schedules
+from .util.chunking import resolver
+from .util.hg import get_hg_commit_message, get_hg_revision_branch
+from .util.partials import populate_release_history
+from .util.taskcluster import insert_index
+from .util.taskgraph import find_decision_task, find_existing_tasks_from_previous_kinds
+
+logger = logging.getLogger(__name__)
+
+ARTIFACTS_DIR = "artifacts"
+
+# For each project, this gives a set of parameters specific to the project.
+# See `taskcluster/docs/parameters.rst` for information on parameters.
+PER_PROJECT_PARAMETERS = {
+    "try": {
+        "enable_always_target": True,
+        "target_tasks_method": "try_tasks",
+    },
+    "kaios-try": {
+        "target_tasks_method": "try_tasks",
+    },
+    "ash": {
+        "target_tasks_method": "default",
+    },
+    "cedar": {
+        "target_tasks_method": "default",
+    },
+    "holly": {
+        "enable_always_target": True,
+        "target_tasks_method": "holly_tasks",
+    },
+    "oak": {
+        "target_tasks_method": "default",
+        "release_type": "nightly-oak",
+    },
+    "graphics": {
+        "target_tasks_method": "graphics_tasks",
+    },
+    "autoland": {
+        "optimize_strategies": "gecko_taskgraph.optimize:project.autoland",
+        "target_tasks_method": "autoland_tasks",
+        "test_manifest_loader": "bugbug",  # Remove this line to disable "manifest scheduling".
+    },
+    "mozilla-central": {
+        "target_tasks_method": "mozilla_central_tasks",
+        "release_type": "nightly",
+    },
+    "mozilla-beta": {
+        "target_tasks_method": "mozilla_beta_tasks",
+        "release_type": "beta",
+    },
+    "mozilla-release": {
+        "target_tasks_method": "mozilla_release_tasks",
+        "release_type": "release",
+    },
+    "mozilla-esr102": {
+        "target_tasks_method": "mozilla_esr102_tasks",
+        "release_type": "esr102",
+    },
+    "mozilla-esr115": {
+        "target_tasks_method": "mozilla_esr115_tasks",
+        "release_type": "esr115",
+    },
+    "pine": {
+        "target_tasks_method": "pine_tasks",
+    },
+    "kaios": {
+        "target_tasks_method": "kaios_tasks",
+    },
+    "toolchains": {
+        "target_tasks_method": "mozilla_central_tasks",
+    },
+    # the default parameters are used for projects that do not match above.
+    "default": {
+        "target_tasks_method": "default",
+    },
+}
+
+try_task_config_schema = Schema(
+    {
+        Required("tasks"): [str],
+        Optional("browsertime"): bool,
+        Optional("chemspill-prio"): bool,
+        Optional("disable-pgo"): bool,
+        Optional("env"): {str: str},
+        Optional("gecko-profile"): bool,
+        Optional("gecko-profile-interval"): float,
+        Optional("gecko-profile-entries"): int,
+        Optional("gecko-profile-features"): str,
+        Optional("gecko-profile-threads"): str,
+        Optional(
+            "perftest-options",
+            description="Options passed from `mach perftest` to try.",
+        ): object,
+        Optional(
+            "optimize-strategies",
+            description="Alternative optimization strategies to use instead of the default. "
+            "A module path pointing to a dict to be use as the `strategy_override` "
+            "argument in `taskgraph.optimize.base.optimize_task_graph`.",
+        ): str,
+        Optional("rebuild"): int,
+        Optional("tasks-regex"): {
+            "include": Any(None, [str]),
+            "exclude": Any(None, [str]),
+        },
+        Optional("use-artifact-builds"): bool,
+        Optional(
+            "worker-overrides",
+            description="Mapping of worker alias to worker pools to use for those aliases.",
+        ): {str: str},
+        Optional("routes"): [str],
+    }
+)
+"""
+Schema for try_task_config.json files.
+"""
+
+try_task_config_schema_v2 = Schema(
+    {
+        Optional("parameters"): {str: object},
+    }
+)
+
+
+def full_task_graph_to_runnable_jobs(full_task_json):
+    runnable_jobs = {}
+    for label, node in full_task_json.items():
+        if not ("extra" in node["task"] and "treeherder" in node["task"]["extra"]):
+            continue
+
+        th = node["task"]["extra"]["treeherder"]
+        runnable_jobs[label] = {"symbol": th["symbol"]}
+
+        for i in ("groupName", "groupSymbol", "collection"):
+            if i in th:
+                runnable_jobs[label][i] = th[i]
+        if th.get("machine", {}).get("platform"):
+            runnable_jobs[label]["platform"] = th["machine"]["platform"]
+    return runnable_jobs
+
+
+def full_task_graph_to_manifests_by_task(full_task_json):
+    manifests_by_task = defaultdict(list)
+    for label, node in full_task_json.items():
+        manifests = node["attributes"].get("test_manifests")
+        if not manifests:
+            continue
+
+        manifests_by_task[label].extend(manifests)
+    return manifests_by_task
+
+
+def try_syntax_from_message(message):
+    """
+    Parse the try syntax out of a commit message, returning '' if none is
+    found.
+    """
+    try_idx = message.find("try:")
+    if try_idx == -1:
+        return ""
+    return message[try_idx:].split("\n", 1)[0]
+
+
+def taskgraph_decision(options, parameters=None):
+    """
+    Run the decision task.  This function implements `mach taskgraph decision`,
+    and is responsible for
+
+     * processing decision task command-line options into parameters
+     * running task-graph generation exactly the same way the other `mach
+       taskgraph` commands do
+     * generating a set of artifacts to memorialize the graph
+     * calling TaskCluster APIs to create the graph
+    """
+
+    parameters = parameters or (
+        lambda graph_config: get_decision_parameters(graph_config, options)
+    )
+
+    decision_task_id = os.environ["TASK_ID"]
+
+    # create a TaskGraphGenerator instance
+    tgg = TaskGraphGenerator(
+        root_dir=options.get("root"),
+        parameters=parameters,
+        decision_task_id=decision_task_id,
+        write_artifacts=True,
+    )
+
+    if not create.testing:
+        # set additional index paths for the decision task
+        set_decision_indexes(decision_task_id, tgg.parameters, tgg.graph_config)
+
+    # write out the parameters used to generate this graph
+    write_artifact("parameters.yml", dict(**tgg.parameters))
+
+    # write out the public/actions.json file
+    write_artifact(
+        "actions.json",
+        render_actions_json(tgg.parameters, tgg.graph_config, decision_task_id),
+    )
+
+    # write out the full graph for reference
+    full_task_json = tgg.full_task_graph.to_json()
+    write_artifact("full-task-graph.json", full_task_json)
+
+    # write out the public/runnable-jobs.json file
+    write_artifact(
+        "runnable-jobs.json", full_task_graph_to_runnable_jobs(full_task_json)
+    )
+
+    # write out the public/manifests-by-task.json file
+    write_artifact(
+        "manifests-by-task.json.gz",
+        full_task_graph_to_manifests_by_task(full_task_json),
+    )
+
+    # write out the public/tests-by-manifest.json file
+    write_artifact("tests-by-manifest.json.gz", resolver.tests_by_manifest)
+
+    # this is just a test to check whether the from_json() function is working
+    _, _ = TaskGraph.from_json(full_task_json)
+
+    # write out the target task set to allow reproducing this as input
+    write_artifact("target-tasks.json", list(tgg.target_task_set.tasks.keys()))
+
+    # write out the optimized task graph to describe what will actually happen,
+    # and the map of labels to taskids
+    write_artifact("task-graph.json", tgg.morphed_task_graph.to_json())
+    write_artifact("label-to-taskid.json", tgg.label_to_taskid)
+
+    # write bugbug scheduling information if it was invoked
+    if len(push_schedules) > 0:
+        write_artifact("bugbug-push-schedules.json", push_schedules.popitem()[1])
+
+    # cache run-task & misc/fetch-content
+    scripts_root_dir = os.path.join(
+        "/builds/worker/checkouts/gecko/taskcluster/scripts"
+    )
+    run_task_file_path = os.path.join(scripts_root_dir, "run-task")
+    fetch_content_file_path = os.path.join(scripts_root_dir, "misc/fetch-content")
+    shutil.copy2(run_task_file_path, ARTIFACTS_DIR)
+    shutil.copy2(fetch_content_file_path, ARTIFACTS_DIR)
+
+    # actually create the graph
+    create_tasks(
+        tgg.graph_config,
+        tgg.morphed_task_graph,
+        tgg.label_to_taskid,
+        tgg.parameters,
+        decision_task_id=decision_task_id,
+    )
+
+
+def get_decision_parameters(graph_config, options):
+    """
+    Load parameters from the command-line options for 'taskgraph decision'.
+    This also applies per-project parameters, based on the given project.
+
+    """
+    product_dir = graph_config["product-dir"]
+
+    parameters = {
+        n: options[n]
+        for n in [
+            "base_repository",
+            "base_ref",
+            "base_rev",
+            "head_repository",
+            "head_rev",
+            "head_ref",
+            "head_tag",
+            "project",
+            "pushlog_id",
+            "pushdate",
+            "owner",
+            "level",
+            "repository_type",
+            "target_tasks_method",
+            "tasks_for",
+        ]
+        if n in options
+    }
+
+    commit_message = get_hg_commit_message(os.path.join(GECKO, product_dir))
+
+    repo_path = os.getcwd()
+    repo = get_repository(repo_path)
+    parameters["base_ref"] = _determine_more_accurate_base_ref(
+        repo,
+        candidate_base_ref=options.get("base_ref"),
+        head_ref=options.get("head_ref"),
+        base_rev=options.get("base_rev"),
+    )
+
+    parameters["base_rev"] = _determine_more_accurate_base_rev(
+        repo,
+        base_ref=parameters["base_ref"],
+        candidate_base_rev=options.get("base_rev"),
+        head_rev=options.get("head_rev"),
+        env_prefix=_get_env_prefix(graph_config),
+    )
+
+    # Define default filter list, as most configurations shouldn't need
+    # custom filters.
+    parameters["filters"] = [
+        "target_tasks_method",
+    ]
+    parameters["enable_always_target"] = False
+    parameters["existing_tasks"] = {}
+    parameters["do_not_optimize"] = []
+    parameters["build_number"] = 1
+    parameters["version"] = get_version(product_dir)
+    parameters["app_version"] = get_app_version(product_dir)
+    parameters["message"] = try_syntax_from_message(commit_message)
+    parameters["hg_branch"] = get_hg_revision_branch(
+        GECKO, revision=parameters["head_rev"]
+    )
+    parameters["next_version"] = None
+    parameters["optimize_strategies"] = None
+    parameters["optimize_target_tasks"] = True
+    parameters["phabricator_diff"] = None
+    parameters["release_type"] = ""
+    parameters["release_eta"] = ""
+    parameters["release_enable_partner_repack"] = False
+    parameters["release_enable_partner_attribution"] = False
+    parameters["release_partners"] = []
+    parameters["release_partner_config"] = {}
+    parameters["release_partner_build_number"] = 1
+    parameters["release_enable_emefree"] = False
+    parameters["release_product"] = None
+    parameters["required_signoffs"] = []
+    parameters["signoff_urls"] = {}
+    parameters["test_manifest_loader"] = "default"
+    parameters["try_mode"] = None
+    parameters["try_task_config"] = {}
+    parameters["try_options"] = None
+
+    # owner must be an email, but sometimes (e.g., for ffxbld) it is not, in which
+    # case, fake it
+    if "@" not in parameters["owner"]:
+        parameters["owner"] += "@noreply.mozilla.org"
+
+    # use the pushdate as build_date if given, else use current time
+    parameters["build_date"] = parameters["pushdate"] or int(time.time())
+    # moz_build_date is the build identifier based on build_date
+    parameters["moz_build_date"] = time.strftime(
+        "%Y%m%d%H%M%S", time.gmtime(parameters["build_date"])
+    )
+
+    project = parameters["project"]
+    try:
+        parameters.update(PER_PROJECT_PARAMETERS[project])
+    except KeyError:
+        logger.warning(
+            "using default project parameters; add {} to "
+            "PER_PROJECT_PARAMETERS in {} to customize behavior "
+            "for this project".format(project, __file__)
+        )
+        parameters.update(PER_PROJECT_PARAMETERS["default"])
+
+    # `target_tasks_method` has higher precedence than `project` parameters
+    if options.get("target_tasks_method"):
+        parameters["target_tasks_method"] = options["target_tasks_method"]
+
+    # ..but can be overridden by the commit message: if it contains the special
+    # string "DONTBUILD" and this is an on-push decision task, then use the
+    # special 'nothing' target task method.
+    if "DONTBUILD" in commit_message and options["tasks_for"] == "hg-push":
+        parameters["target_tasks_method"] = "nothing"
+
+    if options.get("include_push_tasks"):
+        get_existing_tasks(options.get("rebuild_kinds", []), parameters, graph_config)
+
+    # If the target method is nightly, we should build partials. This means
+    # knowing what has been released previously.
+    # An empty release_history is fine, it just means no partials will be built
+    parameters.setdefault("release_history", dict())
+    if "nightly" in parameters.get("target_tasks_method", ""):
+        parameters["release_history"] = populate_release_history("Firefox", project)
+
+    if options.get("try_task_config_file"):
+        task_config_file = os.path.abspath(options.get("try_task_config_file"))
+    else:
+        # if try_task_config.json is present, load it
+        task_config_file = os.path.join(os.getcwd(), "try_task_config.json")
+
+    # load try settings
+    if "try" in project and options["tasks_for"] == "hg-push":
+        set_try_config(parameters, task_config_file)
+
+    if options.get("optimize_target_tasks") is not None:
+        parameters["optimize_target_tasks"] = options["optimize_target_tasks"]
+
+    # Determine if this should be a backstop push.
+    parameters["backstop"] = is_backstop(parameters)
+
+    if "decision-parameters" in graph_config["taskgraph"]:
+        find_object(graph_config["taskgraph"]["decision-parameters"])(
+            graph_config, parameters
+        )
+
+    result = Parameters(**parameters)
+    result.check()
+    return result
+
+
+def get_existing_tasks(rebuild_kinds, parameters, graph_config):
+    """
+    Find the decision task corresponding to the on-push graph, and return
+    a mapping of labels to task-ids from it. This will skip the kinds specificed
+    by `rebuild_kinds`.
+    """
+    try:
+        decision_task = retry(
+            find_decision_task,
+            args=(parameters, graph_config),
+            attempts=4,
+            sleeptime=5 * 60,
+        )
+    except Exception:
+        logger.exception("Didn't find existing push task.")
+        sys.exit(1)
+    _, task_graph = TaskGraph.from_json(
+        get_artifact(decision_task, "public/full-task-graph.json")
+    )
+    parameters["existing_tasks"] = find_existing_tasks_from_previous_kinds(
+        task_graph, [decision_task], rebuild_kinds
+    )
+
+
+def set_try_config(parameters, task_config_file):
+    if os.path.isfile(task_config_file):
+        logger.info(f"using try tasks from {task_config_file}")
+        with open(task_config_file) as fh:
+            task_config = json.load(fh)
+        task_config_version = task_config.pop("version", 1)
+        if task_config_version == 1:
+            validate_schema(
+                try_task_config_schema,
+                task_config,
+                "Invalid v1 `try_task_config.json`.",
+            )
+            parameters["try_mode"] = "try_task_config"
+            parameters["try_task_config"] = task_config
+        elif task_config_version == 2:
+            validate_schema(
+                try_task_config_schema_v2,
+                task_config,
+                "Invalid v2 `try_task_config.json`.",
+            )
+            parameters.update(task_config["parameters"])
+            return
+        else:
+            raise Exception(
+                f"Unknown `try_task_config.json` version: {task_config_version}"
+            )
+
+    if "try:" in parameters["message"]:
+        parameters["try_mode"] = "try_option_syntax"
+        parameters.update(parse_message(parameters["message"]))
+    else:
+        parameters["try_options"] = None
+
+    if parameters["try_mode"] == "try_task_config":
+        # The user has explicitly requested a set of jobs, so run them all
+        # regardless of optimization.  Their dependencies can be optimized,
+        # though.
+        parameters["optimize_target_tasks"] = False
+    else:
+        # For a try push with no task selection, apply the default optimization
+        # process to all of the tasks.
+        parameters["optimize_target_tasks"] = True
+
+
+def set_decision_indexes(decision_task_id, params, graph_config):
+    index_paths = []
+    if params["backstop"]:
+        index_paths.append(BACKSTOP_INDEX)
+
+    subs = params.copy()
+    subs["trust-domain"] = graph_config["trust-domain"]
+
+    index_paths = [i.format(**subs) for i in index_paths]
+    for index_path in index_paths:
+        insert_index(index_path, decision_task_id, use_proxy=True)
+
+
+def write_artifact(filename, data):
+    logger.info(f"writing artifact file `{filename}`")
+    if not os.path.isdir(ARTIFACTS_DIR):
+        os.mkdir(ARTIFACTS_DIR)
+    path = os.path.join(ARTIFACTS_DIR, filename)
+    if filename.endswith(".yml"):
+        with open(path, "w") as f:
+            yaml.safe_dump(data, f, allow_unicode=True, default_flow_style=False)
+    elif filename.endswith(".json"):
+        with open(path, "w") as f:
+            json.dump(data, f, sort_keys=True, indent=2, separators=(",", ": "))
+    elif filename.endswith(".json.gz"):
+        import gzip
+
+        with gzip.open(path, "wb") as f:
+            f.write(json.dumps(data).encode("utf-8"))
+    else:
+        raise TypeError(f"Don't know how to write to {filename}")
+
+
+def read_artifact(filename):
+    path = os.path.join(ARTIFACTS_DIR, filename)
+    if filename.endswith(".yml"):
+        return load_yaml(path, filename)
+    if filename.endswith(".json"):
+        with open(path) as f:
+            return json.load(f)
+    if filename.endswith(".json.gz"):
+        import gzip
+
+        with gzip.open(path, "rb") as f:
+            return json.load(f.decode("utf-8"))
+    else:
+        raise TypeError(f"Don't know how to read {filename}")
+
+
+def rename_artifact(src, dest):
+    os.rename(os.path.join(ARTIFACTS_DIR, src), os.path.join(ARTIFACTS_DIR, dest))
diff --git a/taskcluster/gecko_taskgraph/docker.py b/taskcluster/gecko_taskgraph/docker.py
new file mode 100644
index 0000000000..a1952f278c
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/docker.py
@@ -0,0 +1,198 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+import tarfile
+from io import BytesIO
+
+from taskgraph.generator import load_tasks_for_kind
+from taskgraph.parameters import Parameters
+from taskgraph.util.taskcluster import get_artifact_url, get_session
+
+from gecko_taskgraph.optimize.strategies import IndexSearch
+from gecko_taskgraph.util import docker
+
+from . import GECKO
+
+
+def get_image_digest(image_name):
+    params = Parameters(
+        level=os.environ.get("MOZ_SCM_LEVEL", "3"),
+        strict=False,
+    )
+    tasks = load_tasks_for_kind(params, "docker-image")
+    task = tasks[f"docker-image-{image_name}"]
+    return task.attributes["cached_task"]["digest"]
+
+
+def load_image_by_name(image_name, tag=None):
+    params = {"level": os.environ.get("MOZ_SCM_LEVEL", "3")}
+    tasks = load_tasks_for_kind(params, "docker-image")
+    task = tasks[f"docker-image-{image_name}"]
+    deadline = None
+    task_id = IndexSearch().should_replace_task(
+        task, {}, deadline, task.optimization.get("index-search", [])
+    )
+
+    if task_id in (True, False):
+        print(
+            "Could not find artifacts for a docker image "
+            "named `{image_name}`. Local commits and other changes "
+            "in your checkout may cause this error. Try "
+            "updating to a fresh checkout of mozilla-central "
+            "to download image.".format(image_name=image_name)
+        )
+        return False
+
+    return load_image_by_task_id(task_id, tag)
+
+
+def load_image_by_task_id(task_id, tag=None):
+    artifact_url = get_artifact_url(task_id, "public/image.tar.zst")
+    result = load_image(artifact_url, tag)
+    print("Found docker image: {}:{}".format(result["image"], result["tag"]))
+    if tag:
+        print(f"Re-tagged as: {tag}")
+    else:
+        tag = "{}:{}".format(result["image"], result["tag"])
+    print(f"Try: docker run -ti --rm {tag} bash")
+    return True
+
+
+def build_context(name, outputFile, args=None):
+    """Build a context.tar for image with specified name."""
+    if not name:
+        raise ValueError("must provide a Docker image name")
+    if not outputFile:
+        raise ValueError("must provide a outputFile")
+
+    image_dir = docker.image_path(name)
+    if not os.path.isdir(image_dir):
+        raise Exception("image directory does not exist: %s" % image_dir)
+
+    docker.create_context_tar(GECKO, image_dir, outputFile, image_name=name, args=args)
+
+
+def build_image(name, tag, args=None):
+    """Build a Docker image of specified name.
+
+    Output from image building process will be printed to stdout.
+    """
+    if not name:
+        raise ValueError("must provide a Docker image name")
+
+    image_dir = docker.image_path(name)
+    if not os.path.isdir(image_dir):
+        raise Exception("image directory does not exist: %s" % image_dir)
+
+    tag = tag or docker.docker_image(name, by_tag=True)
+
+    buf = BytesIO()
+    docker.stream_context_tar(GECKO, image_dir, buf, name, args)
+    docker.post_to_docker(buf.getvalue(), "/build", nocache=1, t=tag)
+
+    print(f"Successfully built {name} and tagged with {tag}")
+
+    if tag.endswith(":latest"):
+        print("*" * 50)
+        print("WARNING: no VERSION file found in image directory.")
+        print("Image is not suitable for deploying/pushing.")
+        print("Create an image suitable for deploying/pushing by creating")
+        print("a VERSION file in the image directory.")
+        print("*" * 50)
+
+
+def load_image(url, imageName=None, imageTag=None):
+    """
+    Load docker image from URL as imageName:tag, if no imageName or tag is given
+    it will use whatever is inside the zstd compressed tarball.
+
+    Returns an object with properties 'image', 'tag' and 'layer'.
+    """
+    import zstandard as zstd
+
+    # If imageName is given and we don't have an imageTag
+    # we parse out the imageTag from imageName, or default it to 'latest'
+    # if no imageName and no imageTag is given, 'repositories' won't be rewritten
+    if imageName and not imageTag:
+        if ":" in imageName:
+            imageName, imageTag = imageName.split(":", 1)
+        else:
+            imageTag = "latest"
+
+    info = {}
+
+    def download_and_modify_image():
+        # This function downloads and edits the downloaded tar file on the fly.
+        # It emits chunked buffers of the editted tar file, as a generator.
+        print(f"Downloading from {url}")
+        # get_session() gets us a requests.Session set to retry several times.
+        req = get_session().get(url, stream=True)
+        req.raise_for_status()
+
+        with zstd.ZstdDecompressor().stream_reader(req.raw) as ifh:
+
+            tarin = tarfile.open(
+                mode="r|",
+                fileobj=ifh,
+                bufsize=zstd.DECOMPRESSION_RECOMMENDED_OUTPUT_SIZE,
+            )
+
+            # Stream through each member of the downloaded tar file individually.
+            for member in tarin:
+                # Non-file members only need a tar header. Emit one.
+                if not member.isfile():
+                    yield member.tobuf(tarfile.GNU_FORMAT)
+                    continue
+
+                # Open stream reader for the member
+                reader = tarin.extractfile(member)
+
+                # If member is `repositories`, we parse and possibly rewrite the
+                # image tags.
+                if member.name == "repositories":
+                    # Read and parse repositories
+                    repos = json.loads(reader.read())
+                    reader.close()
+
+                    # If there is more than one image or tag, we can't handle it
+                    # here.
+                    if len(repos.keys()) > 1:
+                        raise Exception("file contains more than one image")
+                    info["image"] = image = list(repos.keys())[0]
+                    if len(repos[image].keys()) > 1:
+                        raise Exception("file contains more than one tag")
+                    info["tag"] = tag = list(repos[image].keys())[0]
+                    info["layer"] = layer = repos[image][tag]
+
+                    # Rewrite the repositories file
+                    data = json.dumps({imageName or image: {imageTag or tag: layer}})
+                    reader = BytesIO(data.encode("utf-8"))
+                    member.size = len(data)
+
+                # Emit the tar header for this member.
+                yield member.tobuf(tarfile.GNU_FORMAT)
+                # Then emit its content.
+                remaining = member.size
+                while remaining:
+                    length = min(remaining, zstd.DECOMPRESSION_RECOMMENDED_OUTPUT_SIZE)
+                    buf = reader.read(length)
+                    remaining -= len(buf)
+                    yield buf
+                # Pad to fill a 512 bytes block, per tar format.
+                remainder = member.size % 512
+                if remainder:
+                    yield ("\0" * (512 - remainder)).encode("utf-8")
+
+                reader.close()
+
+    docker.post_to_docker(download_and_modify_image(), "/images/load", quiet=0)
+
+    # Check that we found a repositories file
+    if not info.get("image") or not info.get("tag") or not info.get("layer"):
+        raise Exception("No repositories file found!")
+
+    return info
diff --git a/taskcluster/gecko_taskgraph/files_changed.py b/taskcluster/gecko_taskgraph/files_changed.py
new file mode 100644
index 0000000000..c814df0806
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/files_changed.py
@@ -0,0 +1,95 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Support for optimizing tasks based on the set of files that have changed.
+"""
+
+import logging
+import os
+from subprocess import CalledProcessError
+
+from mozbuild.util import memoize
+from mozpack.path import join as join_path
+from mozpack.path import match as mozpackmatch
+from mozversioncontrol import InvalidRepoPath, get_repository_object
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.util.hg import get_json_automationrelevance
+
+logger = logging.getLogger(__name__)
+
+
+@memoize
+def get_changed_files(repository, revision):
+    """
+    Get the set of files changed in the push headed by the given revision.
+    Responses are cached, so multiple calls with the same arguments are OK.
+    """
+    contents = get_json_automationrelevance(repository, revision)
+    try:
+        changesets = contents["changesets"]
+    except KeyError:
+        # We shouldn't hit this error in CI.
+        if os.environ.get("MOZ_AUTOMATION"):
+            raise
+
+        # We're likely on an unpublished commit, grab changed files from
+        # version control.
+        return get_locally_changed_files(GECKO)
+
+    logger.debug("{} commits influencing task scheduling:".format(len(changesets)))
+    changed_files = set()
+    for c in changesets:
+        desc = ""  # Support empty desc
+        if c["desc"]:
+            desc = c["desc"].splitlines()[0].encode("ascii", "ignore")
+        logger.debug(" {cset} {desc}".format(cset=c["node"][0:12], desc=desc))
+        changed_files |= set(c["files"])
+
+    return changed_files
+
+
+def check(params, file_patterns):
+    """Determine whether any of the files changed in the indicated push to
+    https://hg.mozilla.org match any of the given file patterns."""
+    repository = params.get("head_repository")
+    revision = params.get("head_rev")
+    if not repository or not revision:
+        logger.warning(
+            "Missing `head_repository` or `head_rev` parameters; "
+            "assuming all files have changed"
+        )
+        return True
+
+    changed_files = get_changed_files(repository, revision)
+
+    if "comm_head_repository" in params:
+        repository = params.get("comm_head_repository")
+        revision = params.get("comm_head_rev")
+        if not revision:
+            logger.warning(
+                "Missing `comm_head_rev` parameters; " "assuming all files have changed"
+            )
+            return True
+
+        changed_files |= {
+            join_path("comm", file) for file in get_changed_files(repository, revision)
+        }
+
+    for pattern in file_patterns:
+        for path in changed_files:
+            if mozpackmatch(path, pattern):
+                return True
+
+    return False
+
+
+@memoize
+def get_locally_changed_files(repo):
+    try:
+        vcs = get_repository_object(repo)
+        return set(vcs.get_outgoing_files("AM"))
+    except (InvalidRepoPath, CalledProcessError):
+        return set()
diff --git a/taskcluster/gecko_taskgraph/loader/__init__.py b/taskcluster/gecko_taskgraph/loader/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/loader/__init__.py
diff --git a/taskcluster/gecko_taskgraph/loader/multi_dep.py b/taskcluster/gecko_taskgraph/loader/multi_dep.py
new file mode 100644
index 0000000000..04fda04415
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/loader/multi_dep.py
@@ -0,0 +1,275 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.task import Task
+from taskgraph.util.schema import Schema
+from voluptuous import Required
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+from ..util.attributes import sorted_unique_list
+
+schema = Schema(
+    {
+        Required("primary-dependency", "primary dependency task"): Task,
+        Required(
+            "dependent-tasks",
+            "dictionary of dependent tasks, keyed by kind",
+        ): {str: Task},
+    }
+)
+
+
+# Define a collection of group_by functions
+GROUP_BY_MAP = {}
+
+
+def group_by(name):
+    def wrapper(func):
+        GROUP_BY_MAP[name] = func
+        return func
+
+    return wrapper
+
+
+def loader(kind, path, config, params, loaded_tasks):
+    """
+    Load tasks based on the jobs dependant kinds, designed for use as
+    multiple-dependent needs.
+
+    Required ``group-by-fn`` is used to define how we coalesce the
+    multiple deps together to pass to transforms, e.g. all kinds specified get
+    collapsed by platform with `platform`
+
+    Optional ``primary-dependency`` (ordered list or string) is used to determine
+    which upstream kind to inherit attrs from. See ``get_primary_dep``.
+
+    The `only-for-build-platforms` kind configuration, if specified, will limit
+    the build platforms for which a job will be created. Alternatively there is
+    'not-for-build-platforms' kind configuration which will be consulted only after
+    'only-for-build-platforms' is checked (if present), and omit any jobs where the
+    build platform matches.
+
+    Optional ``job-template`` kind configuration value, if specified, will be used to
+    pass configuration down to the specified transforms used.
+    """
+    job_template = config.get("job-template")
+
+    for dep_tasks in group_tasks(config, loaded_tasks):
+        job = {"dependent-tasks": dep_tasks}
+        job["primary-dependency"] = get_primary_dep(config, dep_tasks)
+        if job_template:
+            job.update(copy_task(job_template))
+        # copy shipping_product from upstream
+        product = job["primary-dependency"].attributes.get(
+            "shipping_product", job["primary-dependency"].task.get("shipping-product")
+        )
+        if product:
+            job.setdefault("shipping-product", product)
+        job.setdefault("attributes", {})["required_signoffs"] = sorted_unique_list(
+            *(
+                task.attributes.get("required_signoffs", [])
+                for task in dep_tasks.values()
+            )
+        )
+
+        yield job
+
+
+def skip_only_or_not(config, task):
+    """Return True if we should skip this task based on `only_` or `not_` config."""
+    only_platforms = config.get("only-for-build-platforms")
+    not_platforms = config.get("not-for-build-platforms")
+    only_attributes = config.get("only-for-attributes")
+    not_attributes = config.get("not-for-attributes")
+    task_attrs = task.attributes
+    if only_platforms or not_platforms:
+        platform = task_attrs.get("build_platform")
+        build_type = task_attrs.get("build_type")
+        if not platform or not build_type:
+            return True
+        combined_platform = f"{platform}/{build_type}"
+        if only_platforms and combined_platform not in only_platforms:
+            return True
+        if not_platforms and combined_platform in not_platforms:
+            return True
+    if only_attributes:
+        if not set(only_attributes) & set(task_attrs):
+            # make sure any attribute exists
+            return True
+    if not_attributes:
+        if set(not_attributes) & set(task_attrs):
+            return True
+    return False
+
+
+def group_tasks(config, tasks):
+    group_by_fn = GROUP_BY_MAP[config["group-by"]]
+
+    groups = group_by_fn(config, tasks)
+
+    for combinations in groups.values():
+        kinds = [f.kind for f in combinations]
+        assert_unique_members(
+            kinds,
+            error_msg=("Multi_dep.py should have filtered down to one task per kind"),
+        )
+        dependencies = {t.kind: copy_task(t) for t in combinations}
+        yield dependencies
+
+
+@group_by("platform")
+def platform_grouping(config, tasks):
+    groups = {}
+    for task in tasks:
+        if task.kind not in config.get("kind-dependencies", []):
+            continue
+        if skip_only_or_not(config, task):
+            continue
+        platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        product = task.attributes.get(
+            "shipping_product", task.task.get("shipping-product")
+        )
+
+        groups.setdefault((platform, build_type, product), []).append(task)
+    return groups
+
+
+@group_by("single-locale")
+def single_locale_grouping(config, tasks):
+    """Split by a single locale (but also by platform, build-type, product)
+
+    The locale can be `None` (en-US build/signing/repackage), a single locale,
+    or multiple locales per task, e.g. for l10n chunking. In the case of a task
+    with, say, five locales, the task will show up in all five locale groupings.
+
+    This grouping is written for non-partner-repack beetmover, but might also
+    be useful elsewhere.
+
+    """
+    groups = {}
+
+    for task in tasks:
+        if task.kind not in config.get("kind-dependencies", []):
+            continue
+        if skip_only_or_not(config, task):
+            continue
+        platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        product = task.attributes.get(
+            "shipping_product", task.task.get("shipping-product")
+        )
+        task_locale = task.attributes.get("locale")
+        chunk_locales = task.attributes.get("chunk_locales")
+        locales = chunk_locales or [task_locale]
+
+        for locale in locales:
+            locale_key = (platform, build_type, product, locale)
+            groups.setdefault(locale_key, [])
+            if task not in groups[locale_key]:
+                groups[locale_key].append(task)
+
+    return groups
+
+
+@group_by("chunk-locales")
+def chunk_locale_grouping(config, tasks):
+    """Split by a chunk_locale (but also by platform, build-type, product)
+
+    This grouping is written for mac signing with notarization, but might also
+    be useful elsewhere.
+
+    """
+    groups = {}
+
+    for task in tasks:
+        if task.kind not in config.get("kind-dependencies", []):
+            continue
+        if skip_only_or_not(config, task):
+            continue
+        platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        product = task.attributes.get(
+            "shipping_product", task.task.get("shipping-product")
+        )
+        chunk_locales = tuple(sorted(task.attributes.get("chunk_locales", [])))
+
+        chunk_locale_key = (platform, build_type, product, chunk_locales)
+        groups.setdefault(chunk_locale_key, [])
+        if task not in groups[chunk_locale_key]:
+            groups[chunk_locale_key].append(task)
+
+    return groups
+
+
+@group_by("partner-repack-ids")
+def partner_repack_ids_grouping(config, tasks):
+    """Split by partner_repack_ids (but also by platform, build-type, product)
+
+    This grouping is written for release-{eme-free,partner}-repack-signing.
+
+    """
+    groups = {}
+
+    for task in tasks:
+        if task.kind not in config.get("kind-dependencies", []):
+            continue
+        if skip_only_or_not(config, task):
+            continue
+        platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        product = task.attributes.get(
+            "shipping_product", task.task.get("shipping-product")
+        )
+        partner_repack_ids = tuple(
+            sorted(task.task.get("extra", {}).get("repack_ids", []))
+        )
+
+        partner_repack_ids_key = (platform, build_type, product, partner_repack_ids)
+        groups.setdefault(partner_repack_ids_key, [])
+        if task not in groups[partner_repack_ids_key]:
+            groups[partner_repack_ids_key].append(task)
+
+    return groups
+
+
+def assert_unique_members(kinds, error_msg=None):
+    if len(kinds) != len(set(kinds)):
+        raise Exception(error_msg)
+
+
+def get_primary_dep(config, dep_tasks):
+    """Find the dependent task to inherit attributes from.
+
+    If ``primary-dependency`` is defined in ``kind.yml`` and is a string,
+    then find the first dep with that task kind and return it. If it is
+    defined and is a list, the first kind in that list with a matching dep
+    is the primary dependency. If it's undefined, return the first dep.
+
+    """
+    primary_dependencies = config.get("primary-dependency")
+    if isinstance(primary_dependencies, str):
+        primary_dependencies = [primary_dependencies]
+    if not primary_dependencies:
+        assert len(dep_tasks) == 1, "Must define a primary-dependency!"
+        return list(dep_tasks.values())[0]
+    primary_dep = None
+    for primary_kind in primary_dependencies:
+        for dep_kind in dep_tasks:
+            if dep_kind == primary_kind:
+                assert (
+                    primary_dep is None
+                ), "Too many primary dependent tasks in dep_tasks: {}!".format(
+                    [t.label for t in dep_tasks]
+                )
+                primary_dep = dep_tasks[dep_kind]
+    if primary_dep is None:
+        raise Exception(
+            "Can't find dependency of {}: {}".format(
+                config["primary-dependency"], config
+            )
+        )
+    return primary_dep
diff --git a/taskcluster/gecko_taskgraph/loader/single_dep.py b/taskcluster/gecko_taskgraph/loader/single_dep.py
new file mode 100644
index 0000000000..caea4b85d0
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/loader/single_dep.py
@@ -0,0 +1,76 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.task import Task
+from taskgraph.util.schema import Schema
+from voluptuous import Required
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+schema = Schema(
+    {
+        Required("primary-dependency", "primary dependency task"): Task,
+    }
+)
+
+
+def loader(kind, path, config, params, loaded_tasks):
+    """
+    Load tasks based on the jobs dependant kinds.
+
+    The `only-for-build-platforms` kind configuration, if specified, will limit
+    the build platforms for which a job will be created. Alternatively there is
+    'not-for-build-platforms' kind configuration which will be consulted only after
+    'only-for-build-platforms' is checked (if present), and omit any jobs where the
+    build platform matches.
+
+    Optional `only-for-attributes` kind configuration, if specified, will limit
+    the jobs chosen to ones which have the specified attribute, with the specified
+    value.
+
+    Optional `job-template` kind configuration value, if specified, will be used to
+    pass configuration down to the specified transforms used.
+    """
+    only_platforms = config.get("only-for-build-platforms")
+    not_platforms = config.get("not-for-build-platforms")
+    only_attributes = config.get("only-for-attributes")
+    job_template = config.get("job-template")
+
+    for task in loaded_tasks:
+        if task.kind not in config.get("kind-dependencies", []):
+            continue
+
+        if only_platforms or not_platforms:
+            build_platform = task.attributes.get("build_platform")
+            build_type = task.attributes.get("build_type")
+            if not build_platform or not build_type:
+                continue
+            platform = f"{build_platform}/{build_type}"
+            if only_platforms and platform not in only_platforms:
+                continue
+            elif not_platforms and platform in not_platforms:
+                continue
+
+        if only_attributes:
+            config_attrs = set(only_attributes)
+            if not config_attrs & set(task.attributes):
+                # make sure any attribute exists
+                continue
+
+        job = {
+            "primary-dependency": task,
+        }
+
+        if job_template:
+            job.update(copy_task(job_template))
+
+        # copy shipping_product from upstream
+        product = task.attributes.get(
+            "shipping_product", task.task.get("shipping-product")
+        )
+        if product:
+            job.setdefault("shipping-product", product)
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/loader/test.py b/taskcluster/gecko_taskgraph/loader/test.py
new file mode 100644
index 0000000000..c97acecd1a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/loader/test.py
@@ -0,0 +1,142 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from taskgraph.util.yaml import load_yaml
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+from .transform import loader as transform_loader
+
+logger = logging.getLogger(__name__)
+
+
+def loader(kind, path, config, params, loaded_tasks):
+    """
+    Generate tasks implementing Gecko tests.
+    """
+
+    builds_by_platform = get_builds_by_platform(
+        dep_kind="build", loaded_tasks=loaded_tasks
+    )
+    signed_builds_by_platform = get_builds_by_platform(
+        dep_kind="build-signing", loaded_tasks=loaded_tasks
+    )
+
+    # get the test platforms for those build tasks
+    test_platforms_cfg = load_yaml(path, "test-platforms.yml")
+    test_platforms = get_test_platforms(
+        test_platforms_cfg, builds_by_platform, signed_builds_by_platform
+    )
+
+    # expand the test sets for each of those platforms
+    test_sets_cfg = load_yaml(path, "test-sets.yml")
+    test_platforms = expand_tests(test_sets_cfg, test_platforms)
+
+    # load the test descriptions
+    tests = transform_loader(kind, path, config, params, loaded_tasks)
+    test_descriptions = {t.pop("name"): t for t in tests}
+
+    # generate all tests for all test platforms
+    for test_platform_name, test_platform in test_platforms.items():
+        for test_name in test_platform["test-names"]:
+            test = copy_task(test_descriptions[test_name])
+            test["build-platform"] = test_platform["build-platform"]
+            test["test-platform"] = test_platform_name
+            test["build-label"] = test_platform["build-label"]
+            if test_platform.get("build-signing-label", None):
+                test["build-signing-label"] = test_platform["build-signing-label"]
+
+            test["build-attributes"] = test_platform["build-attributes"]
+            test["test-name"] = test_name
+            if test_platform.get("shippable"):
+                test.setdefault("attributes", {})["shippable"] = True
+                test["attributes"]["shipping_product"] = test_platform[
+                    "shipping_product"
+                ]
+
+            logger.debug(
+                "Generating tasks for test {} on platform {}".format(
+                    test_name, test["test-platform"]
+                )
+            )
+            yield test
+
+
+def get_builds_by_platform(dep_kind, loaded_tasks):
+    """Find the build tasks on which tests will depend, keyed by
+    platform/type.  Returns a dictionary mapping build platform to task."""
+    builds_by_platform = {}
+    for task in loaded_tasks:
+        if task.kind != dep_kind:
+            continue
+
+        build_platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        if not build_platform or not build_type:
+            continue
+        platform = f"{build_platform}/{build_type}"
+        if platform in builds_by_platform:
+            raise Exception("multiple build jobs for " + platform)
+        builds_by_platform[platform] = task
+    return builds_by_platform
+
+
+def get_test_platforms(
+    test_platforms_cfg, builds_by_platform, signed_builds_by_platform={}
+):
+    """Get the test platforms for which test tasks should be generated,
+    based on the available build platforms.  Returns a dictionary mapping
+    test platform to {test-set, build-platform, build-label}."""
+    test_platforms = {}
+    for test_platform, cfg in test_platforms_cfg.items():
+        build_platform = cfg["build-platform"]
+        if build_platform not in builds_by_platform:
+            logger.warning(
+                "No build task with platform {}; ignoring test platform {}".format(
+                    build_platform, test_platform
+                )
+            )
+            continue
+        test_platforms[test_platform] = {
+            "build-platform": build_platform,
+            "build-label": builds_by_platform[build_platform].label,
+            "build-attributes": builds_by_platform[build_platform].attributes,
+        }
+
+        if builds_by_platform[build_platform].attributes.get("shippable"):
+            test_platforms[test_platform]["shippable"] = builds_by_platform[
+                build_platform
+            ].attributes["shippable"]
+            test_platforms[test_platform]["shipping_product"] = builds_by_platform[
+                build_platform
+            ].attributes["shipping_product"]
+
+        test_platforms[test_platform].update(cfg)
+
+    return test_platforms
+
+
+def expand_tests(test_sets_cfg, test_platforms):
+    """Expand the test sets in `test_platforms` out to sets of test names.
+    Returns a dictionary like `get_test_platforms`, with an additional
+    `test-names` key for each test platform, containing a set of test
+    names."""
+    rv = {}
+    for test_platform, cfg in test_platforms.items():
+        test_sets = cfg["test-sets"]
+        if not set(test_sets) <= set(test_sets_cfg):
+            raise Exception(
+                "Test sets {} for test platform {} are not defined".format(
+                    ", ".join(test_sets), test_platform
+                )
+            )
+        test_names = set()
+        for test_set in test_sets:
+            test_names.update(test_sets_cfg[test_set])
+        rv[test_platform] = cfg.copy()
+        rv[test_platform]["test-names"] = test_names
+    return rv
diff --git a/taskcluster/gecko_taskgraph/loader/transform.py b/taskcluster/gecko_taskgraph/loader/transform.py
new file mode 100644
index 0000000000..1e513bcb73
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/loader/transform.py
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+from taskgraph.util.yaml import load_yaml
+
+from ..util.templates import merge
+
+logger = logging.getLogger(__name__)
+
+
+def loader(kind, path, config, params, loaded_tasks):
+    """
+    Get the input elements that will be transformed into tasks in a generic
+    way.  The elements themselves are free-form, and become the input to the
+    first transform.
+
+    By default, this reads jobs from the `jobs` key, or from yaml files
+    named by `jobs-from`.  The entities are read from mappings, and the
+    keys to those mappings are added in the `name` key of each entity.
+
+    If there is a `job-defaults` config, then every job is merged with it.
+    This provides a simple way to set default values for all jobs of a kind.
+    The `job-defaults` key can also be specified in a yaml file pointed to by
+    `jobs-from`. In this case it will only apply to tasks defined in the same
+    file.
+
+    Other kind implementations can use a different loader function to
+    produce inputs and hand them to `transform_inputs`.
+    """
+
+    def jobs():
+        defaults = config.get("job-defaults")
+        for name, job in config.get("jobs", {}).items():
+            if defaults:
+                job = merge(defaults, job)
+            job["job-from"] = "kind.yml"
+            yield name, job
+
+        for filename in config.get("jobs-from", []):
+            tasks = load_yaml(path, filename)
+
+            file_defaults = tasks.pop("job-defaults", None)
+            if defaults:
+                file_defaults = merge(defaults, file_defaults or {})
+
+            for name, job in tasks.items():
+                if file_defaults:
+                    job = merge(file_defaults, job)
+                job["job-from"] = filename
+                yield name, job
+
+    for name, job in jobs():
+        job["name"] = name
+        logger.debug(f"Generating tasks for {kind} {name}")
+        yield job
diff --git a/taskcluster/gecko_taskgraph/main.py b/taskcluster/gecko_taskgraph/main.py
new file mode 100644
index 0000000000..bb49ba6000
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/main.py
@@ -0,0 +1,765 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import argparse
+import atexit
+import json
+import logging
+import os
+import re
+import shutil
+import subprocess
+import sys
+import tempfile
+import traceback
+from collections import namedtuple
+from concurrent.futures import ProcessPoolExecutor, as_completed
+from pathlib import Path
+from typing import Any, List
+
+import appdirs
+import yaml
+
+Command = namedtuple("Command", ["func", "args", "kwargs", "defaults"])
+commands = {}
+
+
+def command(*args, **kwargs):
+    defaults = kwargs.pop("defaults", {})
+
+    def decorator(func):
+        commands[args[0]] = Command(func, args, kwargs, defaults)
+        return func
+
+    return decorator
+
+
+def argument(*args, **kwargs):
+    def decorator(func):
+        if not hasattr(func, "args"):
+            func.args = []
+        func.args.append((args, kwargs))
+        return func
+
+    return decorator
+
+
+def format_taskgraph_labels(taskgraph):
+    return "\n".join(
+        sorted(
+            taskgraph.tasks[index].label for index in taskgraph.graph.visit_postorder()
+        )
+    )
+
+
+def format_taskgraph_json(taskgraph):
+    return json.dumps(
+        taskgraph.to_json(), sort_keys=True, indent=2, separators=(",", ": ")
+    )
+
+
+def format_taskgraph_yaml(taskgraph):
+    return yaml.safe_dump(taskgraph.to_json(), default_flow_style=False)
+
+
+def get_filtered_taskgraph(taskgraph, tasksregex):
+    """
+    Filter all the tasks on basis of a regular expression
+    and returns a new TaskGraph object
+    """
+    from taskgraph.graph import Graph
+    from taskgraph.taskgraph import TaskGraph
+
+    # return original taskgraph if no regular expression is passed
+    if not tasksregex:
+        return taskgraph
+    named_links_dict = taskgraph.graph.named_links_dict()
+    filteredtasks = {}
+    filterededges = set()
+    regexprogram = re.compile(tasksregex)
+
+    for key in taskgraph.graph.visit_postorder():
+        task = taskgraph.tasks[key]
+        if regexprogram.match(task.label):
+            filteredtasks[key] = task
+            for depname, dep in named_links_dict[key].items():
+                if regexprogram.match(dep):
+                    filterededges.add((key, dep, depname))
+    filtered_taskgraph = TaskGraph(
+        filteredtasks, Graph(set(filteredtasks), filterededges)
+    )
+    return filtered_taskgraph
+
+
+FORMAT_METHODS = {
+    "labels": format_taskgraph_labels,
+    "json": format_taskgraph_json,
+    "yaml": format_taskgraph_yaml,
+}
+
+
+def get_taskgraph_generator(root, parameters):
+    """Helper function to make testing a little easier."""
+    from taskgraph.generator import TaskGraphGenerator
+
+    return TaskGraphGenerator(root_dir=root, parameters=parameters)
+
+
+def format_taskgraph(options, parameters, logfile=None):
+    import taskgraph
+    from taskgraph.parameters import parameters_loader
+
+    if logfile:
+        handler = logging.FileHandler(logfile, mode="w")
+        if logging.root.handlers:
+            oldhandler = logging.root.handlers[-1]
+            logging.root.removeHandler(oldhandler)
+            handler.setFormatter(oldhandler.formatter)
+        logging.root.addHandler(handler)
+
+    if options["fast"]:
+        taskgraph.fast = True
+
+    if isinstance(parameters, str):
+        parameters = parameters_loader(
+            parameters,
+            overrides={"target-kind": options.get("target_kind")},
+            strict=False,
+        )
+
+    tgg = get_taskgraph_generator(options.get("root"), parameters)
+
+    tg = getattr(tgg, options["graph_attr"])
+    tg = get_filtered_taskgraph(tg, options["tasks_regex"])
+    format_method = FORMAT_METHODS[options["format"] or "labels"]
+    return format_method(tg)
+
+
+def dump_output(out, path=None, params_spec=None):
+    from taskgraph.parameters import Parameters
+
+    params_name = Parameters.format_spec(params_spec)
+    fh = None
+    if path:
+        # Substitute params name into file path if necessary
+        if params_spec and "{params}" not in path:
+            name, ext = os.path.splitext(path)
+            name += "_{params}"
+            path = name + ext
+
+        path = path.format(params=params_name)
+        fh = open(path, "w")
+    else:
+        print(
+            "Dumping result with parameters from {}:".format(params_name),
+            file=sys.stderr,
+        )
+    print(out + "\n", file=fh)
+
+
+def generate_taskgraph(options, parameters, logdir):
+    from taskgraph.parameters import Parameters
+
+    def logfile(spec):
+        """Determine logfile given a parameters specification."""
+        if logdir is None:
+            return None
+        return os.path.join(
+            logdir,
+            "{}_{}.log".format(options["graph_attr"], Parameters.format_spec(spec)),
+        )
+
+    # Don't bother using futures if there's only one parameter. This can make
+    # tracebacks a little more readable and avoids additional process overhead.
+    if len(parameters) == 1:
+        spec = parameters[0]
+        out = format_taskgraph(options, spec, logfile(spec))
+        dump_output(out, options["output_file"])
+        return
+
+    futures = {}
+    with ProcessPoolExecutor() as executor:
+        for spec in parameters:
+            f = executor.submit(format_taskgraph, options, spec, logfile(spec))
+            futures[f] = spec
+
+    for future in as_completed(futures):
+        output_file = options["output_file"]
+        spec = futures[future]
+        e = future.exception()
+        if e:
+            out = "".join(traceback.format_exception(type(e), e, e.__traceback__))
+            if options["diff"]:
+                # Dump to console so we don't accidentally diff the tracebacks.
+                output_file = None
+        else:
+            out = future.result()
+
+        dump_output(
+            out,
+            path=output_file,
+            params_spec=spec if len(parameters) > 1 else None,
+        )
+
+
+@command(
+    "tasks",
+    help="Show all tasks in the taskgraph.",
+    defaults={"graph_attr": "full_task_set"},
+)
+@command(
+    "full", help="Show the full taskgraph.", defaults={"graph_attr": "full_task_graph"}
+)
+@command(
+    "target",
+    help="Show the set of target tasks.",
+    defaults={"graph_attr": "target_task_set"},
+)
+@command(
+    "target-graph",
+    help="Show the target graph.",
+    defaults={"graph_attr": "target_task_graph"},
+)
+@command(
+    "optimized",
+    help="Show the optimized graph.",
+    defaults={"graph_attr": "optimized_task_graph"},
+)
+@command(
+    "morphed",
+    help="Show the morphed graph.",
+    defaults={"graph_attr": "morphed_task_graph"},
+)
+@argument("--root", "-r", help="root of the taskgraph definition relative to topsrcdir")
+@argument("--quiet", "-q", action="store_true", help="suppress all logging output")
+@argument(
+    "--verbose", "-v", action="store_true", help="include debug-level logging output"
+)
+@argument(
+    "--json",
+    "-J",
+    action="store_const",
+    dest="format",
+    const="json",
+    help="Output task graph as a JSON object",
+)
+@argument(
+    "--yaml",
+    "-Y",
+    action="store_const",
+    dest="format",
+    const="yaml",
+    help="Output task graph as a YAML object",
+)
+@argument(
+    "--labels",
+    "-L",
+    action="store_const",
+    dest="format",
+    const="labels",
+    help="Output the label for each task in the task graph (default)",
+)
+@argument(
+    "--parameters",
+    "-p",
+    default=None,
+    action="append",
+    help="Parameters to use for the generation. Can be a path to file (.yml or "
+    ".json; see `taskcluster/docs/parameters.rst`), a directory (containing "
+    "parameters files), a url, of the form `project=mozilla-central` to download "
+    "latest parameters file for the specified project from CI, or of the form "
+    "`task-id=<decision task id>` to download parameters from the specified "
+    "decision task. Can be specified multiple times, in which case multiple "
+    "generations will happen from the same invocation (one per parameters "
+    "specified).",
+)
+@argument(
+    "--no-optimize",
+    dest="optimize",
+    action="store_false",
+    default="true",
+    help="do not remove tasks from the graph that are found in the "
+    "index (a.k.a. optimize the graph)",
+)
+@argument(
+    "-o",
+    "--output-file",
+    default=None,
+    help="file path to store generated output.",
+)
+@argument(
+    "--tasks-regex",
+    "--tasks",
+    default=None,
+    help="only return tasks with labels matching this regular " "expression.",
+)
+@argument(
+    "--target-kind",
+    default=None,
+    help="only return tasks that are of the given kind, or their dependencies.",
+)
+@argument(
+    "-F",
+    "--fast",
+    default=False,
+    action="store_true",
+    help="enable fast task generation for local debugging.",
+)
+@argument(
+    "--diff",
+    const="default",
+    nargs="?",
+    default=None,
+    help="Generate and diff the current taskgraph against another revision. "
+    "Without args the base revision will be used. A revision specifier such as "
+    "the hash or `.~1` (hg) or `HEAD~1` (git) can be used as well.",
+)
+def show_taskgraph(options):
+    from mozversioncontrol import get_repository_object as get_repository
+    from taskgraph.parameters import Parameters, parameters_loader
+
+    if options.pop("verbose", False):
+        logging.root.setLevel(logging.DEBUG)
+
+    repo = None
+    cur_ref = None
+    diffdir = None
+    output_file = options["output_file"]
+
+    if options["diff"]:
+        repo = get_repository(os.getcwd())
+
+        if not repo.working_directory_clean():
+            print(
+                "abort: can't diff taskgraph with dirty working directory",
+                file=sys.stderr,
+            )
+            return 1
+
+        # We want to return the working directory to the current state
+        # as best we can after we're done. In all known cases, using
+        # branch or bookmark (which are both available on the VCS object)
+        # as `branch` is preferable to a specific revision.
+        cur_ref = repo.branch or repo.head_ref[:12]
+
+        diffdir = tempfile.mkdtemp()
+        atexit.register(
+            shutil.rmtree, diffdir
+        )  # make sure the directory gets cleaned up
+        options["output_file"] = os.path.join(
+            diffdir, f"{options['graph_attr']}_{cur_ref}"
+        )
+        print(f"Generating {options['graph_attr']} @ {cur_ref}", file=sys.stderr)
+
+    parameters: List[Any[str, Parameters]] = options.pop("parameters")
+    if not parameters:
+        overrides = {
+            "target-kind": options.get("target_kind"),
+        }
+        parameters = [
+            parameters_loader(None, strict=False, overrides=overrides)
+        ]  # will use default values
+
+    for param in parameters[:]:
+        if isinstance(param, str) and os.path.isdir(param):
+            parameters.remove(param)
+            parameters.extend(
+                [
+                    p.as_posix()
+                    for p in Path(param).iterdir()
+                    if p.suffix in (".yml", ".json")
+                ]
+            )
+
+    logdir = None
+    if len(parameters) > 1:
+        # Log to separate files for each process instead of stderr to
+        # avoid interleaving.
+        basename = os.path.basename(os.getcwd())
+        logdir = os.path.join(appdirs.user_log_dir("taskgraph"), basename)
+        if not os.path.isdir(logdir):
+            os.makedirs(logdir)
+    else:
+        # Only setup logging if we have a single parameter spec. Otherwise
+        # logging will go to files. This is also used as a hook for Gecko
+        # to setup its `mach` based logging.
+        setup_logging()
+
+    generate_taskgraph(options, parameters, logdir)
+
+    if options["diff"]:
+        assert diffdir is not None
+        assert repo is not None
+
+        # Reload taskgraph modules to pick up changes and clear global state.
+        for mod in sys.modules.copy():
+            if mod != __name__ and mod.split(".", 1)[0].endswith(
+                ("taskgraph", "mozbuild")
+            ):
+                del sys.modules[mod]
+
+        # Ensure gecko_taskgraph is ahead of taskcluster_taskgraph in sys.path.
+        # Without this, we may end up validating some things against the wrong
+        # schema.
+        import gecko_taskgraph  # noqa
+
+        if options["diff"] == "default":
+            base_ref = repo.base_ref
+        else:
+            base_ref = options["diff"]
+
+        try:
+            repo.update(base_ref)
+            base_ref = repo.head_ref[:12]
+            options["output_file"] = os.path.join(
+                diffdir, f"{options['graph_attr']}_{base_ref}"
+            )
+            print(f"Generating {options['graph_attr']} @ {base_ref}", file=sys.stderr)
+            generate_taskgraph(options, parameters, logdir)
+        finally:
+            repo.update(cur_ref)
+
+        # Generate diff(s)
+        diffcmd = [
+            "diff",
+            "-U20",
+            "--report-identical-files",
+            f"--label={options['graph_attr']}@{base_ref}",
+            f"--label={options['graph_attr']}@{cur_ref}",
+        ]
+
+        non_fatal_failures = []
+        for spec in parameters:
+            base_path = os.path.join(diffdir, f"{options['graph_attr']}_{base_ref}")
+            cur_path = os.path.join(diffdir, f"{options['graph_attr']}_{cur_ref}")
+
+            params_name = None
+            if len(parameters) > 1:
+                params_name = Parameters.format_spec(spec)
+                base_path += f"_{params_name}"
+                cur_path += f"_{params_name}"
+
+            # If the base or cur files are missing it means that generation
+            # failed. If one of them failed but not the other, the failure is
+            # likely due to the patch making changes to taskgraph in modules
+            # that don't get reloaded (safe to ignore). If both generations
+            # failed, there's likely a real issue.
+            base_missing = not os.path.isfile(base_path)
+            cur_missing = not os.path.isfile(cur_path)
+            if base_missing != cur_missing:  # != is equivalent to XOR for booleans
+                non_fatal_failures.append(os.path.basename(base_path))
+                continue
+
+            try:
+                # If the output file(s) are missing, this command will raise
+                # CalledProcessError with a returncode > 1.
+                proc = subprocess.run(
+                    diffcmd + [base_path, cur_path],
+                    stdout=subprocess.PIPE,
+                    stderr=subprocess.PIPE,
+                    universal_newlines=True,
+                    check=True,
+                )
+                diff_output = proc.stdout
+                returncode = 0
+            except subprocess.CalledProcessError as e:
+                # returncode 1 simply means diffs were found
+                if e.returncode != 1:
+                    print(e.stderr, file=sys.stderr)
+                    raise
+                diff_output = e.output
+                returncode = e.returncode
+
+            dump_output(
+                diff_output,
+                # Don't bother saving file if no diffs were found. Log to
+                # console in this case instead.
+                path=None if returncode == 0 else output_file,
+                params_spec=spec if len(parameters) > 1 else None,
+            )
+
+        if non_fatal_failures:
+            failstr = "\n  ".join(sorted(non_fatal_failures))
+            print(
+                "WARNING: Diff skipped for the following generation{s} "
+                "due to failures:\n  {failstr}".format(
+                    s="s" if len(non_fatal_failures) > 1 else "", failstr=failstr
+                ),
+                file=sys.stderr,
+            )
+
+        if options["format"] != "json":
+            print(
+                "If you were expecting differences in task bodies "
+                'you should pass "-J"\n',
+                file=sys.stderr,
+            )
+
+    if len(parameters) > 1:
+        print("See '{}' for logs".format(logdir), file=sys.stderr)
+
+
+@command("build-image", help="Build a Docker image")
+@argument("image_name", help="Name of the image to build")
+@argument(
+    "-t", "--tag", help="tag that the image should be built as.", metavar="name:tag"
+)
+@argument(
+    "--context-only",
+    help="File name the context tarball should be written to."
+    "with this option it will only build the context.tar.",
+    metavar="context.tar",
+)
+def build_image(args):
+    from gecko_taskgraph.docker import build_context, build_image
+
+    if args["context_only"] is None:
+        build_image(args["image_name"], args["tag"], os.environ)
+    else:
+        build_context(args["image_name"], args["context_only"], os.environ)
+
+
+@command(
+    "load-image",
+    help="Load a pre-built Docker image. Note that you need to "
+    "have docker installed and running for this to work.",
+)
+@argument(
+    "--task-id",
+    help="Load the image at public/image.tar.zst in this task, "
+    "rather than searching the index",
+)
+@argument(
+    "-t",
+    "--tag",
+    help="tag that the image should be loaded as. If not "
+    "image will be loaded with tag from the tarball",
+    metavar="name:tag",
+)
+@argument(
+    "image_name",
+    nargs="?",
+    help="Load the image of this name based on the current "
+    "contents of the tree (as built for mozilla-central "
+    "or mozilla-inbound)",
+)
+def load_image(args):
+    from gecko_taskgraph.docker import load_image_by_name, load_image_by_task_id
+
+    if not args.get("image_name") and not args.get("task_id"):
+        print("Specify either IMAGE-NAME or TASK-ID")
+        sys.exit(1)
+    try:
+        if args["task_id"]:
+            ok = load_image_by_task_id(args["task_id"], args.get("tag"))
+        else:
+            ok = load_image_by_name(args["image_name"], args.get("tag"))
+        if not ok:
+            sys.exit(1)
+    except Exception:
+        traceback.print_exc()
+        sys.exit(1)
+
+
+@command("image-digest", help="Print the digest of a docker image.")
+@argument(
+    "image_name",
+    help="Print the digest of the image of this name based on the current "
+    "contents of the tree.",
+)
+def image_digest(args):
+    from gecko_taskgraph.docker import get_image_digest
+
+    try:
+        digest = get_image_digest(args["image_name"])
+        print(digest)
+    except Exception:
+        traceback.print_exc()
+        sys.exit(1)
+
+
+@command("decision", help="Run the decision task")
+@argument("--root", "-r", help="root of the taskgraph definition relative to topsrcdir")
+@argument(
+    "--message",
+    required=False,
+    help=argparse.SUPPRESS,
+)
+@argument(
+    "--project",
+    required=True,
+    help="Project to use for creating task graph. Example: --project=try",
+)
+@argument("--pushlog-id", dest="pushlog_id", required=True, default="0")
+@argument("--pushdate", dest="pushdate", required=True, type=int, default=0)
+@argument("--owner", required=True, help="email address of who owns this graph")
+@argument("--level", required=True, help="SCM level of this repository")
+@argument(
+    "--target-tasks-method", help="method for selecting the target tasks to generate"
+)
+@argument(
+    "--repository-type",
+    required=True,
+    help='Type of repository, either "hg" or "git"',
+)
+@argument("--base-repository", required=True, help='URL for "base" repository to clone')
+@argument(
+    "--base-ref", default="", help='Reference of the revision in the "base" repository'
+)
+@argument(
+    "--base-rev",
+    default="",
+    help="Taskgraph decides what to do based on the revision range between "
+    "`--base-rev` and `--head-rev`. Value is determined automatically if not provided",
+)
+@argument(
+    "--head-repository",
+    required=True,
+    help='URL for "head" repository to fetch revision from',
+)
+@argument(
+    "--head-ref", required=True, help="Reference (this is same as rev usually for hg)"
+)
+@argument(
+    "--head-rev", required=True, help="Commit revision to use from head repository"
+)
+@argument("--head-tag", help="Tag attached to the revision", default="")
+@argument(
+    "--tasks-for", required=True, help="the tasks_for value used to generate this task"
+)
+@argument("--try-task-config-file", help="path to try task configuration file")
+def decision(options):
+    from gecko_taskgraph.decision import taskgraph_decision
+
+    taskgraph_decision(options)
+
+
+@command("action-callback", description="Run action callback used by action tasks")
+@argument(
+    "--root",
+    "-r",
+    default="taskcluster/ci",
+    help="root of the taskgraph definition relative to topsrcdir",
+)
+def action_callback(options):
+    from gecko_taskgraph.actions import trigger_action_callback
+    from gecko_taskgraph.actions.util import get_parameters
+
+    try:
+        # the target task for this action (or null if it's a group action)
+        task_id = json.loads(os.environ.get("ACTION_TASK_ID", "null"))
+        # the target task group for this action
+        task_group_id = os.environ.get("ACTION_TASK_GROUP_ID", None)
+        input = json.loads(os.environ.get("ACTION_INPUT", "null"))
+        callback = os.environ.get("ACTION_CALLBACK", None)
+        root = options["root"]
+
+        parameters = get_parameters(task_group_id)
+
+        return trigger_action_callback(
+            task_group_id=task_group_id,
+            task_id=task_id,
+            input=input,
+            callback=callback,
+            parameters=parameters,
+            root=root,
+            test=False,
+        )
+    except Exception:
+        traceback.print_exc()
+        sys.exit(1)
+
+
+@command("test-action-callback", description="Run an action callback in a testing mode")
+@argument(
+    "--root",
+    "-r",
+    default="taskcluster/ci",
+    help="root of the taskgraph definition relative to topsrcdir",
+)
+@argument(
+    "--parameters",
+    "-p",
+    default="",
+    help="parameters file (.yml or .json; see " "`taskcluster/docs/parameters.rst`)`",
+)
+@argument("--task-id", default=None, help="TaskId to which the action applies")
+@argument(
+    "--task-group-id", default=None, help="TaskGroupId to which the action applies"
+)
+@argument("--input", default=None, help="Action input (.yml or .json)")
+@argument("callback", default=None, help="Action callback name (Python function name)")
+def test_action_callback(options):
+    import taskgraph.parameters
+    from taskgraph.config import load_graph_config
+    from taskgraph.util import yaml
+
+    import gecko_taskgraph.actions
+
+    def load_data(filename):
+        with open(filename) as f:
+            if filename.endswith(".yml"):
+                return yaml.load_stream(f)
+            if filename.endswith(".json"):
+                return json.load(f)
+            raise Exception(f"unknown filename {filename}")
+
+    try:
+        task_id = options["task_id"]
+
+        if options["input"]:
+            input = load_data(options["input"])
+        else:
+            input = None
+
+        root = options["root"]
+        graph_config = load_graph_config(root)
+        trust_domain = graph_config["trust-domain"]
+        graph_config.register()
+
+        parameters = taskgraph.parameters.load_parameters_file(
+            options["parameters"], strict=False, trust_domain=trust_domain
+        )
+        parameters.check()
+
+        return gecko_taskgraph.actions.trigger_action_callback(
+            task_group_id=options["task_group_id"],
+            task_id=task_id,
+            input=input,
+            callback=options["callback"],
+            parameters=parameters,
+            root=root,
+            test=True,
+        )
+    except Exception:
+        traceback.print_exc()
+        sys.exit(1)
+
+
+def create_parser():
+    parser = argparse.ArgumentParser(description="Interact with taskgraph")
+    subparsers = parser.add_subparsers()
+    for _, (func, args, kwargs, defaults) in commands.items():
+        subparser = subparsers.add_parser(*args, **kwargs)
+        for arg in func.args:
+            subparser.add_argument(*arg[0], **arg[1])
+        subparser.set_defaults(command=func, **defaults)
+    return parser
+
+
+def setup_logging():
+    logging.basicConfig(
+        format="%(asctime)s - %(levelname)s - %(message)s", level=logging.INFO
+    )
+
+
+def main(args=sys.argv[1:]):
+    setup_logging()
+    parser = create_parser()
+    args = parser.parse_args(args)
+    try:
+        args.command(vars(args))
+    except Exception:
+        traceback.print_exc()
+        sys.exit(1)
diff --git a/taskcluster/gecko_taskgraph/manifests/fennec_geckoview.yml b/taskcluster/gecko_taskgraph/manifests/fennec_geckoview.yml
new file mode 100644
index 0000000000..18974d3c19
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/fennec_geckoview.yml
@@ -0,0 +1,210 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+s3_bucket_paths:
+    - maven2
+default_locales:  # Ignored for geckoview
+    - en-US
+tasktype_map:  # Map task reference to task type.
+    build: build
+    build-fat-aar: build
+    build-signing: signing
+
+# A default entry, which the mappings below extend and override.
+# Final 'destinations' will be the product of:
+# s3_bucket_paths + destinations + locale_prefix + pretty_name
+default: &default
+    locale_prefix: ''
+    source_path_modifier: maven/org/mozilla/geckoview/${artifact_id}/${major_version}.${minor_version}.${build_date}
+    description: "TO_BE_OVERRIDDEN"
+    destinations:  # locale_prefix is appended
+        - org/mozilla/geckoview/${artifact_id}/${major_version}.${minor_version}.${build_date}
+
+mapping:
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.asc:
+        <<: *default
+        from: ['build-signing']
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.asc
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.asc
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.md5:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.md5
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.md5
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha1:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha1
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha1
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha256:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha256
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha256
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha512:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha512
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.aar.sha512
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.asc:
+        <<: *default
+        from: ['build-signing']
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.asc
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.asc
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.md5:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.md5
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.md5
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha1:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha1
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha1
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha256:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha256
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha256
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha512:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha512
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.pom.sha512
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.asc:
+        <<: *default
+        from: ['build-signing']
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.asc
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.asc
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.md5:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.md5
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.md5
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha1:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha1
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha1
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha256:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha256
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha256
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha512:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha512
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}.module.sha512
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.asc:
+        <<: *default
+        from: ['build-signing']
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.asc
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.asc
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.md5:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.md5
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.md5
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha1:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha1
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha1
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha256:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha256
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha256
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha512:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha512
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-javadoc.jar.sha512
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.asc:
+        <<: *default
+        from: ['build-signing']
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.asc
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.asc
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.md5:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.md5
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.md5
+    ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.sha1:
+        <<: *default
+        from:
+            - build
+            - build-fat-aar
+        pretty_name: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.sha1
+        checksums_path: ${artifact_id}-${major_version}.${minor_version}.${build_date}-sources.jar.sha1
diff --git a/taskcluster/gecko_taskgraph/manifests/firefox_candidates.yml b/taskcluster/gecko_taskgraph/manifests/firefox_candidates.yml
new file mode 100644
index 0000000000..e8d7061c78
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/firefox_candidates.yml
@@ -0,0 +1,430 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+# This file contains exhaustive information about all the release artifacs that
+# are needed within a type of release.
+#
+# Structure
+# --------
+# `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
+# `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
+#                      destinations. If given an empty locale, it uses these locales instead.
+# `tasktype_map`          -- mapping between task reference and task type, particularly usefule when
+#                      composing the upstreamArtifacts for scriptworker.
+# `platform_names`        -- various platform mappings used in reckoning artifacts or other paths
+# `default`               -- a default entry, which the mappings extend and override in such a way that
+#                      final path full-destinations will be a concatenation of the following:
+#                      `s3_bucket_paths`, `destinations`, `locale_prefix`, `pretty_name`
+# `from`                  -- specifies the dependency(ies) from which to expect the particular artifact
+# `all_locales`           -- boolean argument to specify whether that particular artifact is to be expected
+#                      for all locales or just the default one
+# `description`           -- brief summary of what that artifact is
+# `locale_prefix`         -- prefix to be used in the final destination paths, whether that's for default locale or not
+# `source_path_modifier`  -- any parent dir that might be used in between artifact prefix and filename at source location
+#                            for example `public/build` vs `public/build/ach/`.
+# `destinations`          -- final list of directories where to push the artifacts in S3
+# `pretty_name`           -- the final name the artifact will have at destination
+# `checksums_path`        -- the name to identify one artifact within the checksums file
+# `not_for_platforms`     -- filtering option to avoid associating an artifact with a specific platform
+# `only_for_platforms`    -- filtering option to exclusively include the association of an artifact for a specific platform
+# `partials_only`         -- filtering option to avoid associating an artifact unless this flag is present
+# `update_balrog_manifest`-- flag needed downstream in beetmover jobs to reckon the balrog manifest
+# `from_buildid`          -- flag needed downstream in beetmover jobs to reckon the balrog manifest
+
+s3_bucket_paths:
+    by-platform:
+        .*devedition.*:
+            - pub/devedition/candidates
+        default:
+            - pub/firefox/candidates
+default_locales:
+    - en-US
+tasktype_map:
+    build: build
+    signing: signing
+    mar-signing: signing
+    partials-signing: signing
+    repackage: repackage
+    repackage-deb: repackage
+    repackage-deb-l10n: repackage
+    repackage-signing: repackage
+    repackage-signing-msi: repackage
+    repackage-signing-shippable-l10n-msix: signing
+    langpack-copy: scriptworker
+    attribution: build
+    attribution-l10n: build
+platform_names:
+    path_platform:
+        by-platform:
+            linux-shippable: 'linux-i686'
+            linux-devedition: 'linux-i686'
+            linux64-shippable: 'linux-x86_64'
+            linux64-devedition: 'linux-x86_64'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'mac'
+            macosx64-devedition: 'mac'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+    tools_platform:
+        by-platform:
+            linux-shippable: 'linux'
+            linux-devedition: 'linux-devedition'
+            linux64-shippable: 'linux64'
+            linux64-devedition: 'linux64-devedition'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'macosx64'
+            macosx64-devedition: 'macosx64-devedition'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32-devedition'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64-devedition'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64-devedition'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+    filename_platform:
+        by-platform:
+            linux-shippable: 'linux'
+            linux-devedition: 'linux'
+            linux64-shippable: 'linux64'
+            linux64-devedition: 'linux64'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'macosx64'
+            macosx64-devedition: 'macosx64'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64_aarch64'
+            win64-aarch64-devedition: 'win64_aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+
+default: &default
+    from:
+        - build
+    all_locales: false
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: '${locale}/'
+    source_path_modifier:
+        by-locale:
+            default: '${locale}'
+            en-US: ''
+    destinations:
+        - ${version}-candidates/build${build_number}/${path_platform}
+
+mapping:
+    buildhub.json:
+        <<: *default
+        all_locales: false
+        description: "Build related information to be consumed by Buildhub service"
+        pretty_name: buildhub.json
+        checksums_path: ${path_platform}/${locale}/buildhub.json
+    target.common.tests.tar.gz:
+        <<: *default
+        description: "Mixture of reftests, mochitests, UI and others, commonly bundled together in a test suite"
+        pretty_name: firefox-${version}.common.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.common.tests.tar.gz
+    target.cppunittest.tests.tar.gz:
+        <<: *default
+        description: "C++ unittests related in-tree test infrastructure"
+        pretty_name: firefox-${version}.cppunittest.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.cppunittest.tests.tar.gz
+    target.crashreporter-symbols.zip:
+        <<: *default
+        description: "Crashreporter symbols to be consumed by Socorro"
+        pretty_name: firefox-${version}.crashreporter-symbols.zip
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.crashreporter-symbols.zip
+    target.json:
+        <<: *default
+        description: "Various compile and moz_app flags baked together in a json file"
+        pretty_name: firefox-${version}.json
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.json
+    target.mochitest.tests.tar.gz:
+        <<: *default
+        description: "Results for running the mochitest testing framework via Javascript function calls"
+        pretty_name: firefox-${version}.mochitest.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.mochitest.tests.tar.gz
+    target.mozinfo.json:
+        <<: *default
+        description: "Various compile and moz_app flags baked together in a json file"
+        pretty_name: firefox-${version}.mozinfo.json
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.mozinfo.json
+    target.reftest.tests.tar.gz:
+        <<: *default
+        description: "Results for running the reftest testing framework via display of two Web pages comparison"
+        pretty_name: firefox-${version}.reftest.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.reftest.tests.tar.gz
+    target.talos.tests.tar.gz:
+        <<: *default
+        description: "Results for running the talos testing framework to measure performance"
+        pretty_name: firefox-${version}.talos.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.talos.tests.tar.gz
+    target.awsy.tests.tar.gz:
+        <<: *default
+        description: "Results for running the awsy testing framework to track memory usage"
+        pretty_name: firefox-${version}.awsy.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.awsy.tests.tar.gz
+    target.test_packages.json:
+        <<: *default
+        description: "File containing metadata about all other files and testing harnesses specifics"
+        pretty_name: firefox-${version}.test_packages.json
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.test_packages.json
+    target.web-platform.tests.tar.gz:
+        <<: *default
+        description: "Results for running the webplatform testing framework to cover standard Web platform features"
+        pretty_name: firefox-${version}.web-platform.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.web-platform.tests.tar.gz
+    target.xpcshell.tests.tar.gz:
+        <<: *default
+        description: "Results for running the xpcshell testing framework to enable XPConnect console application"
+        pretty_name: firefox-${version}.xpcshell.tests.tar.gz
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.xpcshell.tests.tar.gz
+    target_info.txt:
+        <<: *default
+        description: "File containing the buildID"
+        locale_prefix: ''
+        pretty_name: ${filename_platform}_info.txt
+        checksums_path: ${filename_platform}_info.txt
+        destinations:
+            - ${version}-candidates/build${build_number}
+    mozharness.zip:
+        <<: *default
+        description: "File containing the mozharness set of scripts and configuration used by various automation tools"
+        pretty_name: mozharness.zip
+        checksums_path: ${path_platform}/${locale}/mozharness.zip
+    target.jsshell.zip:
+        <<: *default
+        description: "Set of shells to allow test snippets of Javascript code without needing to reload the page"
+        locale_prefix: ''
+        pretty_name: jsshell-${path_platform}.zip
+        checksums_path: jsshell/jsshell-${path_platform}.zip
+        destinations:
+            - ${version}-candidates/build${build_number}/jsshell
+    target.langpack.xpi:
+        <<: *default
+        all_locales: true
+        description: "Localized repack that grabs a packaged en-US Firefox and repackages it as locale-specific Firefox"
+        locale_prefix: ''
+        from:
+            - langpack-copy
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux64-devedition
+            - macosx64-shippable
+            - win32-shippable
+            - win64-shippable
+        pretty_name: ${locale}.xpi
+        checksums_path: ${path_platform}/xpi/${locale}.xpi
+        destinations:
+            - ${version}-candidates/build${build_number}/${path_platform}/xpi
+    target.langpack.deb:
+        <<: *default
+        all_locales: true
+        description: "langpack.xpi repackaged as a .deb"
+        locale_prefix: ''
+        from:
+            - repackage-deb-l10n
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux-devedition
+            - linux64-devedition
+        pretty_name: ${locale}.deb
+        checksums_path: ${path_platform}/deb-l10n/${locale}.deb
+        destinations:
+            - ${version}-candidates/build${build_number}/${path_platform}/deb-l10n
+        update_balrog_manifest: false
+    mar:
+        <<: *default
+        description: "Alongside `mbsdiff`, a tool used to generate partials"
+        locale_prefix: ''
+        source_path_modifier: 'host/bin'
+        pretty_name: ${tools_platform}/mar
+        checksums_path: mar-tools/${tools_platform}/mar
+        not_for_platforms:
+            - win32-shippable
+            - win64-shippable
+            - win64-aarch64-shippable
+            - win32-devedition
+            - win64-devedition
+            - win64-aarch64-devedition
+        destinations:
+            - ${version}-candidates/build${build_number}/mar-tools
+    mbsdiff:
+        <<: *default
+        description: "Alongside `mar`, a tool used to generate partials"
+        locale_prefix: ''
+        source_path_modifier: 'host/bin'
+        pretty_name: ${tools_platform}/mbsdiff
+        checksums_path: mar-tools/${tools_platform}/mbsdiff
+        not_for_platforms:
+            - win32-shippable
+            - win64-shippable
+            - win64-aarch64-shippable
+            - win32-devedition
+            - win64-devedition
+            - win64-aarch64-devedition
+        destinations:
+            - ${version}-candidates/build${build_number}/mar-tools
+    target.tar.bz2:
+        <<: *default
+        description: "Main installer for Linux platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux-devedition
+            - linux64-devedition
+        pretty_name: firefox-${version}.tar.bz2
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.tar.bz2
+    target.tar.bz2.asc:
+        <<: *default
+        description: "Detached signature for the checksums file"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux-devedition
+            - linux64-devedition
+        pretty_name: firefox-${version}.tar.bz2.asc
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.tar.bz2.asc
+    target.pkg:
+        <<: *default
+        description: "Main package installer for Mac OS X platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - macosx64-shippable
+        pretty_name: Firefox ${version}.pkg
+        checksums_path: ${path_platform}/${locale}/Firefox ${version}.pkg
+    target.dmg:
+        <<: *default
+        description: "Main package disk image for Mac OS X platforms"
+        all_locales: true
+        from:
+            - repackage
+        only_for_platforms:
+            - macosx64-shippable
+            - macosx64-devedition
+        pretty_name: Firefox ${version}.dmg
+        checksums_path: ${path_platform}/${locale}/Firefox ${version}.dmg
+    target.zip:
+        <<: *default
+        description: "Main package installer for Windows platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-aarch64-shippable
+            - win64-devedition
+            - win32-devedition
+            - win64-aarch64-devedition
+        pretty_name: firefox-${version}.zip
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.zip
+    target.installer.exe:
+        <<: *default
+        description: "Main installer for Windows platforms"
+        all_locales: true
+        source_path_modifier: ''
+        from:
+            - attribution
+            - attribution-l10n
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-aarch64-shippable
+            - win64-devedition
+            - win32-devedition
+            - win64-aarch64-devedition
+        pretty_name: Firefox Setup ${version}.exe
+        checksums_path: ${path_platform}/${locale}/Firefox Setup ${version}.exe
+    target.stub-installer.exe:
+        <<: *default
+        description: "Stub installer for Win32 platforms"
+        all_locales: true
+        source_path_modifier: ''
+        from:
+            - attribution
+            - attribution-l10n
+        only_for_platforms:
+            - win32-shippable
+            - win32-devedition
+        pretty_name: Firefox Installer.exe
+        checksums_path: ${path_platform}/${locale}/Firefox Installer.exe
+    target.installer.msi:
+        <<: *default
+        description: "Windows installer for MSI platform"
+        all_locales: true
+        from:
+            - repackage-signing-msi
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-devedition
+            - win32-devedition
+        pretty_name: Firefox Setup ${version}.msi
+        checksums_path: ${path_platform}/${locale}/Firefox Setup ${version}.msi
+    target.installer.msix:
+        <<: *default
+        description: "Windows MSIX installer"
+        from:
+            - repackage-signing-shippable-l10n-msix
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-devedition
+            - win32-devedition
+        locale_prefix: 'multi/'
+        pretty_name: Firefox Setup ${version}.msix
+        checksums_path: ${path_platform}/multi/Firefox Setup ${version}.msix
+    target.complete.mar:
+        <<: *default
+        description: "Complete MAR to serve as updates"
+        all_locales: true
+        from:
+            - mar-signing
+        pretty_name: firefox-${version}.complete.mar
+        checksums_path: update/${path_platform}/${locale}/firefox-${version}.complete.mar
+        update_balrog_manifest: true
+        destinations:
+            - ${version}-candidates/build${build_number}/update/${path_platform}
+    target.deb:
+        <<: *default
+        description: "Firefox as a .deb package"
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux-devedition
+            - linux64-devedition
+        pretty_name: firefox-${version}.deb
+        checksums_path: ${path_platform}/${locale}/firefox-${version}.deb
+        from:
+            - repackage-deb
+        update_balrog_manifest: false
+    ${partial}:
+        <<: *default
+        description: "Partials MAR files to serve as updates"
+        all_locales: true
+        from:
+            - partials-signing
+        partials_only: true
+        pretty_name: firefox-${previous_version}-${version}.partial.mar
+        checksums_path: update/${path_platform}/${locale}/firefox-${previous_version}-${version}.partial.mar
+        update_balrog_manifest: true
+        from_buildid: ${from_buildid}
+        destinations:
+            - ${version}-candidates/build${build_number}/update/${path_platform}
diff --git a/taskcluster/gecko_taskgraph/manifests/firefox_candidates_checksums.yml b/taskcluster/gecko_taskgraph/manifests/firefox_candidates_checksums.yml
new file mode 100644
index 0000000000..43ba4cbf15
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/firefox_candidates_checksums.yml
@@ -0,0 +1,94 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+# This file contains exhaustive information about all the release artifacs that
+# are needed within a type of release.
+#
+# Structure
+# --------
+# `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
+# `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
+#                      destinations. If given an empty locale, it uses these locales instead.
+# `tasktype_map`          -- mapping between task reference and task type, particularly usefule when
+#                      composing the upstreamArtifacts for scriptworker.
+# `platform_names`        -- various platform mappings used in reckoning artifacts or other paths
+# `default`               -- a default entry, which the mappings extend and override in such a way that
+#                      final path full-destinations will be a concatenation of the following:
+#                      `s3_bucket_paths`, `destinations`, `locale_prefix`, `pretty_name`
+# `from`                  -- specifies the dependency(ies) from which to expect the particular artifact
+# `all_locales`           -- boolean argument to specify whether that particular artifact is to be expected
+#                      for all locales or just the default one
+# `description`           -- brief summary of what that artifact is
+# `locale_prefix`         -- prefix to be used in the final destination paths, whether that's for default locale or not
+# `source_path_modifier`  -- any parent dir that might be used in between artifact prefix and filename at source location
+#                            for example `public/build` vs `public/build/ach/`.
+# `destinations`          -- final list of directories where to push the artifacts in S3
+# `pretty_name`           -- the final name the artifact will have at destination
+# `checksums_path`        -- the name to identify one artifact within the checksums file
+# `not_for_platforms`     -- filtering option to avoid associating an artifact with a specific platform
+# `only_for_platforms`    -- filtering option to exclusively include the association of an artifact for a specific platform
+# `partials_only`         -- filtering option to avoid associating an artifact unless this flag is present
+# `update_balrog_manifest`-- flag needed downstream in beetmover jobs to reckon the balrog manifest
+# `from_buildid`          -- flag needed downstream in beetmover jobs to reckon the balrog manifest
+
+s3_bucket_paths:
+    by-platform:
+        .*devedition.*:
+            - pub/devedition/candidates
+        default:
+            - pub/firefox/candidates
+default_locales:
+    - en-US
+tasktype_map:
+    beetmover-repackage: beetmover
+    release-beetmover-signed-langpacks: signing
+platform_names:
+    path_platform:
+        by-platform:
+            linux-shippable: 'linux-i686'
+            linux-devedition: 'linux-i686'
+            linux64-shippable: 'linux-x86_64'
+            linux64-devedition: 'linux-x86_64'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'mac'
+            macosx64-devedition: 'mac'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+            linux: 'linux-i686'
+            linux64: 'linux-x86_64'
+            macosx64: 'mac'
+            win32: 'win32'
+            win64: 'win64'
+
+default: &default
+    from:
+        - beetmover-repackage
+    all_locales: true
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: '${locale}/'
+    source_path_modifier: ''
+    destinations:
+        - ${version}-candidates/build${build_number}/beetmover-checksums/${path_platform}
+
+mapping:
+    target.checksums:
+        <<: *default
+        description: "Checksums file containing size, hash, sha algorithm and filename"
+        pretty_name: firefox-${version}.checksums.beet
+        checksums_path: beetmover-checksums/${path_platform}/${locale}/firefox-${version}.checksums.beet
+    target-langpack.checksums:
+        <<: *default
+        description: "Checksums file containing size, hash, sha algorithm and filename for the langpack"
+        locale_prefix: ''
+        from:
+            - release-beetmover-signed-langpacks
+        pretty_name: ${locale}.checksums.beet
+        checksums_path: beetmover-checksums/${path_platform}/xpi/${locale}.checksums.beet
+        destinations:
+            - ${version}-candidates/build${build_number}/beetmover-checksums/${path_platform}/xpi
diff --git a/taskcluster/gecko_taskgraph/manifests/firefox_nightly.yml b/taskcluster/gecko_taskgraph/manifests/firefox_nightly.yml
new file mode 100644
index 0000000000..d2e4f6adf0
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/firefox_nightly.yml
@@ -0,0 +1,520 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+# This file contains exhaustive information about all the release artifacs that
+# are needed within a type of release.
+#
+# Structure
+# --------
+# `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
+# `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
+#                      destinations. If given an empty locale, it uses these locales instead.
+# `tasktype_map`          -- mapping between task reference and task type, particularly usefule when
+#                      composing the upstreamArtifacts for scriptworker.
+# `platform_names`        -- various platform mappings used in reckoning artifacts or other paths
+# `default`               -- a default entry, which the mappings extend and override in such a way that
+#                      final path full-destinations will be a concatenation of the following:
+#                      `s3_bucket_paths`, `destinations`, `locale_prefix`, `pretty_name`
+# `from`                  -- specifies the dependency(ies) from which to expect the particular artifact
+# `all_locales`           -- boolean argument to specify whether that particular artifact is to be expected
+#                      for all locales or just the default one
+# `description`           -- brief summary of what that artifact is
+# `locale_prefix`         -- prefix to be used in the final destination paths, whether that's for default locale or not
+# `source_path_modifier`  -- any parent dir that might be used in between artifact prefix and filename at source location
+#                            for example `public/build` vs `public/build/ach/`.
+# `destinations`          -- final list of directories where to push the artifacts in S3
+# `pretty_name`           -- the final name the artifact will have at destination
+# `checksums_path`        -- the name to identify one artifact within the checksums file
+# `not_for_platforms`     -- filtering option to avoid associating an artifact with a specific platform
+# `only_for_platforms`    -- filtering option to exclusively include the association of an artifact for a specific platform
+# `partials_only`         -- filtering option to avoid associating an artifact unless this flag is present
+# `update_balrog_manifest`-- flag needed downstream in beetmover jobs to reckon the balrog manifest
+# `from_buildid`          -- flag needed downstream in beetmover jobs to reckon the balrog manifest
+
+s3_bucket_paths:
+    - pub/firefox/nightly
+default_locales:
+    - en-US
+tasktype_map:
+    build: build
+    signing: signing
+    mar-signing: signing
+    partials-signing: signing
+    repackage: repackage
+    repackage-deb: repackage
+    repackage-deb-l10n: repackage
+    repackage-signing: repackage
+    repackage-signing-msi: repackage
+    repackage-signing-shippable-l10n-msix: signing
+    langpack-copy: signing
+    attribution: build
+    attribution-l10n: build
+platform_names:
+    filename_platform:
+        by-platform:
+            linux-shippable: 'linux-i686'
+            linux-devedition: 'linux-i686'
+            linux64-shippable: 'linux-x86_64'
+            linux64-devedition: 'linux-x86_64'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'mac'
+            macosx64-devedition: 'mac'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+    stage_platform:
+        by-platform:
+            linux-shippable: 'linux'
+            linux-devedition: 'linux'
+            linux64-asan-reporter-shippable: 'linux64-asan-reporter'
+            linux64-shippable: 'linux64'
+            linux64-devedition: 'linux64'
+            macosx64-shippable: 'macosx64'
+            macosx64-devedition: 'macosx64'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+
+default: &default
+    from:
+        - build
+    all_locales: false
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: ''
+    source_path_modifier:
+        by-locale:
+            default: '${locale}'
+            en-US: ''
+    destinations:
+        by-locale:
+            en-US:
+                - ${year}/${month}/${upload_date}-${branch}
+                - latest-${branch}
+            default:
+                - ${year}/${month}/${upload_date}-${branch}-l10n
+                - latest-${branch}-l10n
+
+mapping:
+    buildhub.json:
+        <<: *default
+        description: "Build related information to be consumed by Buildhub service"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.buildhub.json
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.buildhub.json
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    KEY:
+        <<: *default
+        from:
+            - signing
+        description: "Public GPG Key"
+        pretty_name: KEY
+        checksums_path: KEY
+        only_for_platforms:
+            - linux64-shippable
+        destinations:
+            - ${year}/${month}/${upload_date}-${branch}
+            - latest-${branch}
+    target.common.tests.tar.gz:
+        <<: *default
+        description: "Mixture of reftests, mochitests, UI and others, commonly bundled together in a test suite"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.common.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.common.tests.tar.gz
+    target.cppunittest.tests.tar.gz:
+        <<: *default
+        description: "C++ unittests related in-tree test infrastructure"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.cppunittest.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.cppunittest.tests.tar.gz
+    target.crashreporter-symbols.zip:
+        <<: *default
+        description: "Crashreporter symbols to be consumed by Socorro"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.crashreporter-symbols.zip
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.crashreporter-symbols.zip
+        not_for_platforms:
+            - linux64-asan-reporter-shippable
+            - win64-asan-reporter-shippable
+    target.json:
+        <<: *default
+        description: "Various compile and moz_app flags baked together in a json file"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.json
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.json
+    target.mochitest.tests.tar.gz:
+        <<: *default
+        description: "Results for running the mochitest testing framework via Javascript function calls"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.mochitest.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.mochitest.tests.tar.gz
+    target.mozinfo.json:
+        <<: *default
+        description: "Various compile and moz_app flags baked together in a json file"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.mozinfo.json
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.mozinfo.json
+    target.reftest.tests.tar.gz:
+        <<: *default
+        description: "Results for running the reftest testing framework via display of two Web pages comparison"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.reftest.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.reftest.tests.tar.gz
+    target.talos.tests.tar.gz:
+        <<: *default
+        description: "Results for running the talos testing framework to measure performance"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.talos.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.talos.tests.tar.gz
+    target.awsy.tests.tar.gz:
+        <<: *default
+        description: "Results for running the awsy testing framework to track memory usage"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.awsy.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.awsy.tests.tar.gz
+    target.test_packages.json:
+        <<: *default
+        description: "File containing metadata about all other files and testing harnesses specifics"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.test_packages.json
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.test_packages.json
+    target.txt:
+        <<: *default
+        description: "File containing buildid and revision"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.txt
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.txt
+    target.web-platform.tests.tar.gz:
+        <<: *default
+        description: "Results for running the webplatform testing framework to cover standard Web platform features"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.web-platform.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.web-platform.tests.tar.gz
+    target.xpcshell.tests.tar.gz:
+        <<: *default
+        description: "Results for running the xpcshell testing framework to enable XPConnect console application"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.xpcshell.tests.tar.gz
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.xpcshell.tests.tar.gz
+    target_info.txt:
+        <<: *default
+        description: "File containing the buildID"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}_info.txt
+        checksums_path: firefox-${version}.${locale}.${filename_platform}_info.txt
+    mozharness.zip:
+        <<: *default
+        description: "File containing the mozharness set of scripts and configuration used by various automation tools"
+        pretty_name: mozharness.zip
+        checksums_path: mozharness.zip
+    target.jsshell.zip:
+        <<: *default
+        description: "Set of shells to allow test snippets of Javascript code without needing to reload the page"
+        pretty_name: jsshell-${filename_platform}.zip
+        checksums_path: jsshell-${filename_platform}.zip
+        not_for_platforms:
+            - linux64-asan-reporter-shippable
+            - win64-asan-reporter-shippable
+    target.langpack.xpi:
+        <<: *default
+        all_locales: true
+        description: "Localized repack that grabs a packaged en-US Firefox and repackages it as locale-specific Firefox"
+        from:
+            - langpack-copy
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - macosx64-shippable
+            - win64-shippable
+            - win32-shippable
+            - win64-shippable
+            - win64-aarch64-shippable
+            - win64-asan-reporter-shippable
+            - linux64-asan-reporter-shippable
+        pretty_name: firefox-${version}.${locale}.langpack.xpi
+        checksums_path: firefox-${version}.${locale}.langpack.xpi
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n/${filename_platform}/xpi
+                    - latest-${branch}-l10n/${filename_platform}/xpi
+    target.langpack.deb:
+        <<: *default
+        all_locales: true
+        description: "langpack.xpi repackaged as a .deb"
+        from:
+            - repackage-deb-l10n
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux-devedition
+            - linux64-devedition
+        pretty_name: firefox-${version}.${locale}.langpack.deb
+        checksums_path: firefox-${version}.${locale}.langpack.deb
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n/${filename_platform}/deb-l10n
+                    - latest-${branch}-l10n/${filename_platform}/deb-l10n
+    mar:
+        <<: *default
+        description: "Alongside `mbsdiff`, a tool used to generate partials"
+        source_path_modifier: 'host/bin'
+        pretty_name: mar
+        checksums_path: mar
+        not_for_platforms:
+            - win32-shippable
+            - win64-shippable
+            - win64-aarch64-shippable
+            - win64-asan-reporter-shippable
+        destinations:
+            - ${year}/${month}/${upload_date}-${branch}/mar-tools/${stage_platform}
+            - latest-${branch}/mar-tools/${stage_platform}
+    mbsdiff:
+        <<: *default
+        description: "Alongside `mar`, a tool used to generate partials"
+        source_path_modifier: 'host/bin'
+        pretty_name: mbsdiff
+        checksums_path: mbsdiff
+        not_for_platforms:
+            - win32-shippable
+            - win64-shippable
+            - win64-aarch64-shippable
+            - win64-asan-reporter-shippable
+        destinations:
+            - ${year}/${month}/${upload_date}-${branch}/mar-tools/${stage_platform}
+            - latest-${branch}/mar-tools/${stage_platform}
+    target.tar.bz2:
+        <<: *default
+        description: "Main installer for Linux platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux64-asan-reporter-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.tar.bz2
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.tar.bz2
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.tar.bz2.asc:
+        <<: *default
+        description: "Detached signature for the checksums file"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+            - linux64-asan-reporter-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.tar.bz2.asc
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.tar.bz2.asc
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.pkg:
+        <<: *default
+        description: "Main package installer for Mac OS X platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - macosx64-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.pkg
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.pkg
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.dmg:
+        <<: *default
+        description: "Main package disk image for Mac OS X platforms"
+        all_locales: true
+        from:
+            - repackage
+        only_for_platforms:
+            - macosx64-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.dmg
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.dmg
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.zip:
+        <<: *default
+        description: "Main package installer for Windows platforms"
+        all_locales: true
+        from:
+            - signing
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-aarch64-shippable
+            - win64-asan-reporter-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.zip
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.zip
+    target.installer.exe:
+        <<: *default
+        description: "Main installer for Windows platforms"
+        all_locales: true
+        source_path_modifier: ''
+        from:
+            by-platform:
+                win64-asan-reporter-shippable:
+                    - repackage-signing
+                default:
+                    - attribution
+                    - attribution-l10n
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+            - win64-aarch64-shippable
+            - win64-asan-reporter-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.installer.exe
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.installer.exe
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.stub-installer.exe:
+        <<: *default
+        description: "Stub installer for Win32 platforms"
+        all_locales: true
+        source_path_modifier: ''
+        from:
+            - attribution
+            - attribution-l10n
+        only_for_platforms:
+            - win32-shippable
+        pretty_name: Firefox Installer.${locale}.exe
+        checksums_path: Firefox Installer.${locale}.exe
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.installer.msi:
+        <<: *default
+        description: "Windows installer for MSI platform"
+        all_locales: true
+        from:
+            - repackage-signing-msi
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.installer.msi
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.installer.msi
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.installer.msix:
+        <<: *default
+        description: "Windows MSIX installer"
+        all_locales: true
+        from:
+            - repackage-signing-shippable-l10n-msix
+        only_for_platforms:
+            - win64-shippable
+            - win32-shippable
+        pretty_name: firefox-${version}.multi.${filename_platform}.installer.msix
+        checksums_path: firefox-${version}.multi.${filename_platform}.installer.msix
+        destinations:
+            - ${year}/${month}/${upload_date}-${branch}
+            - latest-${branch}
+            - latest-${branch}-l10n
+    target.complete.mar:
+        <<: *default
+        description: "The main installer we ship our products baked within"
+        all_locales: true
+        from:
+            - mar-signing
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.complete.mar
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.complete.mar
+        update_balrog_manifest: true
+        destinations:
+            by-locale:
+                en-US:
+                    - ${year}/${month}/${upload_date}-${branch}
+                    - latest-${branch}
+                    - latest-${branch}-l10n
+                default:
+                    - ${year}/${month}/${upload_date}-${branch}-l10n
+                    - latest-${branch}-l10n
+    target.deb:
+        <<: *default
+        description: "Firefox as a .deb package"
+        from:
+            - repackage-deb
+        only_for_platforms:
+            - linux-shippable
+            - linux64-shippable
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.deb
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.deb
+        update_balrog_manifest: false
+        destinations:
+            - ${year}/${month}/${upload_date}-${branch}
+            - latest-${branch}
+    ${partial}:
+        <<: *default
+        description: "Partials MAR files to serve as updates"
+        all_locales: true
+        from:
+            - partials-signing
+        partials_only: true
+        pretty_name: firefox-${branch}-${version}-${filename_platform}-${locale}-${from_buildid}-${buildid}.partial.mar
+        checksums_path: firefox-${branch}-${version}-${filename_platform}-${locale}-${from_buildid}-${buildid}.partial.mar
+        update_balrog_manifest: true
+        from_buildid: ${from_buildid}
+        destinations:
+            by-locale:
+                en-US:
+                    - partials/${year}/${month}/${upload_date}-${branch}
+                default:
+                    - partials/${year}/${month}/${upload_date}-${branch}-l10n
diff --git a/taskcluster/gecko_taskgraph/manifests/firefox_nightly_checksums.yml b/taskcluster/gecko_taskgraph/manifests/firefox_nightly_checksums.yml
new file mode 100644
index 0000000000..f1b81572ab
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/firefox_nightly_checksums.yml
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+s3_bucket_paths:
+    by-platform:
+        .*devedition.*:
+            - pub/devedition/nightly
+        default:
+            - pub/firefox/nightly
+default_locales:  # if given an empty locale, use these locales
+    - en-US
+tasktype_map:  # Map task reference to task type.
+    beetmover-repackage: beetmover
+platform_names:
+    filename_platform:
+        by-platform:
+            linux-shippable: 'linux-i686'
+            linux-devedition: 'linux-i686'
+            linux64-shippable: 'linux-x86_64'
+            linux64-devedition: 'linux-x86_64'
+            linux64-asan-reporter-shippable: 'linux-x86_64-asan-reporter'
+            macosx64-shippable: 'mac'
+            macosx64-devedition: 'mac'
+            win32-shippable: 'win32'
+            win32-devedition: 'win32'
+            win64-shippable: 'win64'
+            win64-devedition: 'win64'
+            win64-aarch64-shippable: 'win64-aarch64'
+            win64-aarch64-devedition: 'win64-aarch64'
+            win64-asan-reporter-shippable: 'win64-asan-reporter'
+
+# A default entry, which the mappings below extend and override.
+# Final 'destinations' will be the product of:
+# s3_bucket_paths + destinations + locale_prefix + pretty_name
+default: &default
+    from:
+        - beetmover-repackage
+    all_locales: true
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: ''
+    source_path_modifier: ''
+    destinations:  # locale_prefix is appended
+        by-locale:
+            en-US:
+                - ${year}/${month}/${upload_date}-${branch}
+                - latest-${branch}
+                - latest-${branch}-l10n
+            default:
+                - ${year}/${month}/${upload_date}-${branch}-l10n
+                - latest-${branch}-l10n
+
+# Configuration for individual files. Extends 'default', above.
+mapping:
+    target.checksums:
+        <<: *default
+        description: "Checksums file containing size, hash, sha algorithm and filename"
+        pretty_name: firefox-${version}.${locale}.${filename_platform}.checksums
+        checksums_path: firefox-${version}.${locale}.${filename_platform}.checksums
diff --git a/taskcluster/gecko_taskgraph/manifests/release_checksums.yml b/taskcluster/gecko_taskgraph/manifests/release_checksums.yml
new file mode 100644
index 0000000000..c11e339958
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/release_checksums.yml
@@ -0,0 +1,70 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+s3_bucket_paths:
+    by-platform:
+        devedition-release:
+            - pub/devedition/candidates
+        firefox-release:
+            - pub/firefox/candidates
+default_locales:  # if given an empty locale, use these locales
+    - en-US
+tasktype_map:  # Map task reference to task type.
+    release-generate-checksums: build
+    release-generate-checksums-signing: signing
+
+# A default entry, which the mappings below extend and override.
+# Final 'destinations' will be the product of:
+# s3_bucket_paths + destinations + locale_prefix + pretty_name
+default: &default
+    from:
+        - release-generate-checksums-signing
+    all_locales: true
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: ''
+    source_path_modifier: ''
+    destinations:  # locale_prefix is appended
+        - ${version}-candidates/build${build_number}
+
+# Configuration for individual files. Extends 'default', above.
+mapping:
+    SHA256SUMMARY:
+        <<: *default
+        description: "Merkle-tree for the release artifacts with sha 256 hashes"
+        from:
+            - release-generate-checksums
+        pretty_name: SHA256SUMMARY
+        checksums_path: SHA256SUMMARY
+    SHA512SUMMARY:
+        <<: *default
+        description: "Merkle-tree for the release artifacts with sha 512 hashes"
+        from:
+            - release-generate-checksums
+        pretty_name: SHA512SUMMARY
+        checksums_path: SHA512SUMMARY
+    KEY:
+        <<: *default
+        description: "Public side of the key that was used to sign the release artifacts"
+        pretty_name: KEY
+        checksums_path: KEY
+    SHA256SUMS:
+        <<: *default
+        description: "Aggregated checksums with main installers details per platform in sha512 hashes"
+        pretty_name: SHA256SUMS
+        checksums_path: SHA256SUMS
+    SHA256SUMS.asc:
+        <<: *default
+        description: "Detached signature for the checksums file"
+        pretty_name: SHA256SUMS.asc
+        checksums_path: SHA256SUMS.asc
+    SHA512SUMS:
+        <<: *default
+        description: "Aggregated checksums with main installers details per platform in sha256 hashes"
+        pretty_name: SHA512SUMS
+        checksums_path: SHA512SUMS
+    SHA512SUMS.asc:
+        <<: *default
+        description: "Detached signature for the checksums file"
+        pretty_name: SHA512SUMS.asc
+        checksums_path: SHA512SUMS.asc
diff --git a/taskcluster/gecko_taskgraph/manifests/source_checksums.yml b/taskcluster/gecko_taskgraph/manifests/source_checksums.yml
new file mode 100644
index 0000000000..0789bcfa93
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/source_checksums.yml
@@ -0,0 +1,52 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+s3_bucket_paths:
+    by-platform:
+        devedition-source:
+            - pub/devedition/candidates
+        firefox-source:
+            - pub/firefox/candidates
+default_locales:  # if given an empty locale, use these locales
+    - en-US
+tasktype_map:  # Map task reference to task type.
+    release-source-checksums-signing: signing
+
+# A default entry, which the mappings below extend and override.
+# Final 'destinations' will be the product of:
+# s3_bucket_paths + destinations + locale_prefix + pretty_name
+default: &default
+    from:
+        - release-source-checksums-signing
+    all_locales: false
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: ''
+    source_path_modifier: ''
+    destinations:  # locale_prefix is appended
+        - ${version}-candidates/build${build_number}/beetmover-checksums/source
+
+# Configuration for individual files. Extends 'default', above.
+mapping:
+    target-source.checksums:
+        <<: *default
+        description: "Checksums file for the source zip files"
+        pretty_name:
+            by-platform:
+                firefox-source: firefox-${version}.checksums.beet
+                devedition-source: firefox-${version}.checksums.beet
+        checksums_path:
+            by-platform:
+                firefox-source: firefox-${version}.checksums.beet
+                devedition-source: firefox-${version}.checksums.beet
+    target-source.checksums.asc:
+        <<: *default
+        description: "Detached signature for the checksums file"
+        pretty_name:
+            by-platform:
+                firefox-source: firefox-${version}.checksums.asc
+                devedition-source: firefox-${version}.checksums.asc
+        checksums_path:
+            by-platform:
+                firefox-source: firefox-${version}.checksums.asc
+                devedition-source: firefox-${version}.checksums.asc
diff --git a/taskcluster/gecko_taskgraph/manifests/source_files.yml b/taskcluster/gecko_taskgraph/manifests/source_files.yml
new file mode 100644
index 0000000000..0f5f5b5250
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/manifests/source_files.yml
@@ -0,0 +1,52 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+---
+s3_bucket_paths:
+    by-platform:
+        devedition-source:
+            - pub/devedition/candidates
+        firefox-source:
+            - pub/firefox/candidates
+default_locales:  # if given an empty locale, use these locales
+    - en-US
+tasktype_map:  # Map task reference to task type.
+    release-source-signing: signing
+
+# A default entry, which the mappings below extend and override.
+# Final 'destinations' will be the product of:
+# s3_bucket_paths + destinations + locale_prefix + pretty_name
+default: &default
+    from:
+        - release-source-signing
+    all_locales: false
+    description: "TO_BE_OVERRIDDEN"
+    locale_prefix: ''
+    source_path_modifier: ''
+    destinations:  # locale_prefix is appended
+        - ${version}-candidates/build${build_number}/source
+
+# Configuration for individual files. Extends 'default', above.
+mapping:
+    source.tar.xz:
+        <<: *default
+        description: "Source file with the in-tree code archived"
+        pretty_name:
+            by-platform:
+                firefox-source: firefox-${version}.source.tar.xz
+                devedition-source: firefox-${version}.source.tar.xz
+        checksums_path:
+            by-platform:
+                firefox-source: source/firefox-${version}.source.tar.xz
+                devedition-source: source/firefox-${version}.source.tar.xz
+    source.tar.xz.asc:
+        <<: *default
+        description: "Detached signature for the source file"
+        pretty_name:
+            by-platform:
+                firefox-source: firefox-${version}.source.tar.xz.asc
+                devedition-source: firefox-${version}.source.tar.xz.asc
+        checksums_path:
+            by-platform:
+                firefox-source: source/firefox-${version}.source.tar.xz.asc
+                devedition-source: source/firefox-${version}.source.tar.xz.asc
diff --git a/taskcluster/gecko_taskgraph/morph.py b/taskcluster/gecko_taskgraph/morph.py
new file mode 100644
index 0000000000..1d03ddaab6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/morph.py
@@ -0,0 +1,263 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Graph morphs are modifications to task-graphs that take place *after* the
+optimization phase.
+
+These graph morphs are largely invisible to developers running `./mach`
+locally, so they should be limited to changes that do not modify the meaning of
+the graph.
+"""
+
+# Note that the translation of `{'task-reference': '..'}` and
+# `artifact-reference` are handled in the optimization phase (since
+# optimization involves dealing with taskIds directly).  Similarly,
+# `{'relative-datestamp': '..'}` is handled at the last possible moment during
+# task creation.
+
+
+import copy
+import logging
+import os
+import re
+
+from slugid import nice as slugid
+from taskgraph.graph import Graph
+from taskgraph.morph import register_morph
+from taskgraph.task import Task
+from taskgraph.taskgraph import TaskGraph
+
+from .util.workertypes import get_worker_type
+
+here = os.path.abspath(os.path.dirname(__file__))
+logger = logging.getLogger(__name__)
+MAX_ROUTES = 10
+
+
+def amend_taskgraph(taskgraph, label_to_taskid, to_add):
+    """Add the given tasks to the taskgraph, returning a new taskgraph"""
+    new_tasks = taskgraph.tasks.copy()
+    new_edges = set(taskgraph.graph.edges)
+    for task in to_add:
+        new_tasks[task.task_id] = task
+        assert task.label not in label_to_taskid
+        label_to_taskid[task.label] = task.task_id
+        for depname, dep in task.dependencies.items():
+            new_edges.add((task.task_id, dep, depname))
+
+    taskgraph = TaskGraph(new_tasks, Graph(set(new_tasks), new_edges))
+    return taskgraph, label_to_taskid
+
+
+def derive_misc_task(
+    target_task,
+    purpose,
+    image,
+    taskgraph,
+    label_to_taskid,
+    parameters,
+    graph_config,
+    dependencies,
+):
+    """Create the shell of a task that depends on `dependencies` and on the given docker
+    image."""
+    label = f"{purpose}-{target_task.label}"
+
+    # this is why all docker image tasks are included in the target task graph: we
+    # need to find them in label_to_taskid, even if nothing else required them
+    image_taskid = label_to_taskid["docker-image-" + image]
+
+    provisioner_id, worker_type = get_worker_type(
+        graph_config,
+        parameters,
+        "misc",
+    )
+
+    deps = copy.copy(dependencies)
+    deps["docker-image"] = image_taskid
+
+    task_def = {
+        "provisionerId": provisioner_id,
+        "workerType": worker_type,
+        "dependencies": [d for d in deps.values()],
+        "created": {"relative-datestamp": "0 seconds"},
+        "deadline": target_task.task["deadline"],
+        # no point existing past the parent task's deadline
+        "expires": target_task.task["deadline"],
+        "metadata": {
+            "name": label,
+            "description": f"{purpose} for {target_task.description}",
+            "owner": target_task.task["metadata"]["owner"],
+            "source": target_task.task["metadata"]["source"],
+        },
+        "scopes": [],
+        "payload": {
+            "image": {
+                "path": "public/image.tar.zst",
+                "taskId": image_taskid,
+                "type": "task-image",
+            },
+            "features": {"taskclusterProxy": True},
+            "maxRunTime": 600,
+        },
+    }
+
+    if image_taskid not in taskgraph.tasks:
+        # The task above depends on the replaced docker-image not one in
+        # this current graph.
+        del deps["docker-image"]
+
+    task = Task(
+        kind="misc",
+        label=label,
+        attributes={},
+        task=task_def,
+        dependencies=deps,
+    )
+    task.task_id = slugid()
+    return task
+
+
+# these regular expressions capture route prefixes for which we have a star
+# scope, allowing them to be summarized.  Each should correspond to a star scope
+# in each Gecko `assume:repo:hg.mozilla.org/...` role.
+SCOPE_SUMMARY_REGEXPS = [
+    re.compile(r"(index:insert-task:docker\.images\.v1\.[^.]*\.).*"),
+    re.compile(r"(index:insert-task:gecko\.v2\.[^.]*\.).*"),
+    re.compile(r"(index:insert-task:comm\.v2\.[^.]*\.).*"),
+]
+
+
+def make_index_task(
+    parent_task,
+    taskgraph,
+    label_to_taskid,
+    parameters,
+    graph_config,
+    index_paths,
+    index_rank,
+    purpose,
+    dependencies,
+):
+    task = derive_misc_task(
+        parent_task,
+        purpose,
+        "index-task",
+        taskgraph,
+        label_to_taskid,
+        parameters,
+        graph_config,
+        dependencies,
+    )
+
+    # we need to "summarize" the scopes, otherwise a particularly
+    # namespace-heavy index task might have more scopes than can fit in a
+    # temporary credential.
+    scopes = set()
+    for path in index_paths:
+        scope = f"index:insert-task:{path}"
+        for summ_re in SCOPE_SUMMARY_REGEXPS:
+            match = summ_re.match(scope)
+            if match:
+                scope = match.group(1) + "*"
+                break
+        scopes.add(scope)
+    task.task["scopes"] = sorted(scopes)
+
+    task.task["payload"]["command"] = ["insert-indexes.js"] + index_paths
+    task.task["payload"]["env"] = {
+        "TARGET_TASKID": parent_task.task_id,
+        "INDEX_RANK": index_rank,
+    }
+    return task
+
+
+@register_morph
+def add_index_tasks(taskgraph, label_to_taskid, parameters, graph_config):
+    """
+    The TaskCluster queue only allows 10 routes on a task, but we have tasks
+    with many more routes, for purposes of indexing. This graph morph adds
+    "index tasks" that depend on such tasks and do the index insertions
+    directly, avoiding the limits on task.routes.
+    """
+    logger.debug("Morphing: adding index tasks")
+
+    # Add indexes for tasks that exceed MAX_ROUTES.
+    added = []
+    for label, task in taskgraph.tasks.items():
+        if len(task.task.get("routes", [])) <= MAX_ROUTES:
+            continue
+        index_paths = [
+            r.split(".", 1)[1] for r in task.task["routes"] if r.startswith("index.")
+        ]
+        task.task["routes"] = [
+            r for r in task.task["routes"] if not r.startswith("index.")
+        ]
+        added.append(
+            make_index_task(
+                task,
+                taskgraph,
+                label_to_taskid,
+                parameters,
+                graph_config,
+                index_paths=index_paths,
+                index_rank=task.task.get("extra", {}).get("index", {}).get("rank", 0),
+                purpose="index-task",
+                dependencies={"parent": task.task_id},
+            )
+        )
+
+    if added:
+        taskgraph, label_to_taskid = amend_taskgraph(taskgraph, label_to_taskid, added)
+        logger.info(f"Added {len(added)} index tasks")
+
+    return taskgraph, label_to_taskid
+
+
+@register_morph
+def add_eager_cache_index_tasks(taskgraph, label_to_taskid, parameters, graph_config):
+    """
+    Some tasks (e.g. cached tasks) we want to exist in the index before they even
+    run/complete. Our current use is to allow us to depend on an unfinished cached
+    task in future pushes. This graph morph adds "eager-index tasks" that depend on
+    the decision task and do the index insertions directly, which does not need to
+    wait on the pointed at task to complete.
+    """
+    logger.debug("Morphing: Adding eager cached index's")
+
+    added = []
+    for label, task in taskgraph.tasks.items():
+        if "eager_indexes" not in task.attributes:
+            continue
+        eager_indexes = task.attributes["eager_indexes"]
+        added.append(
+            make_index_task(
+                task,
+                taskgraph,
+                label_to_taskid,
+                parameters,
+                graph_config,
+                index_paths=eager_indexes,
+                index_rank=0,  # Be sure complete tasks get priority
+                purpose="eager-index",
+                dependencies={},
+            )
+        )
+
+    if added:
+        taskgraph, label_to_taskid = amend_taskgraph(taskgraph, label_to_taskid, added)
+        logger.info(f"Added {len(added)} eager index tasks")
+    return taskgraph, label_to_taskid
+
+
+@register_morph
+def add_try_task_duplicates(taskgraph, label_to_taskid, parameters, graph_config):
+    try_config = parameters["try_task_config"]
+    rebuild = try_config.get("rebuild")
+    if rebuild:
+        for task in taskgraph.tasks.values():
+            if task.label in try_config.get("tasks", []):
+                task.attributes["task_duplicates"] = rebuild
+    return taskgraph, label_to_taskid
diff --git a/taskcluster/gecko_taskgraph/optimize/__init__.py b/taskcluster/gecko_taskgraph/optimize/__init__.py
new file mode 100644
index 0000000000..c2d3fdf839
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/optimize/__init__.py
@@ -0,0 +1,287 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+The objective of optimization is to remove as many tasks from the graph as
+possible, as efficiently as possible, thereby delivering useful results as
+quickly as possible.  For example, ideally if only a test script is modified in
+a push, then the resulting graph contains only the corresponding test suite
+task.
+
+See ``taskcluster/docs/optimization.rst`` for more information.
+"""
+
+from taskgraph.optimize.base import Alias, All, Any, Not, register_strategy, registry
+from taskgraph.util.python_path import import_sibling_modules
+
+# Use the gecko_taskgraph version of 'skip-unless-changed' for now.
+registry.pop("skip-unless-changed", None)
+
+# Trigger registration in sibling modules.
+import_sibling_modules()
+
+
+def split_bugbug_arg(arg, substrategies):
+    """Split args for bugbug based strategies.
+
+    Many bugbug based optimizations require passing an empty dict by reference
+    to communicate to downstream strategies. This function passes the provided
+    arg to the first (non bugbug) strategies and a shared empty dict to the
+    bugbug strategy and all substrategies after it.
+    """
+    from gecko_taskgraph.optimize.bugbug import BugBugPushSchedules
+
+    index = [
+        i
+        for i, strategy in enumerate(substrategies)
+        if isinstance(strategy, BugBugPushSchedules)
+    ][0]
+
+    return [arg] * index + [{}] * (len(substrategies) - index)
+
+
+# Register composite strategies.
+register_strategy("build", args=("skip-unless-schedules",))(Alias)
+register_strategy("test", args=("skip-unless-schedules",))(Alias)
+register_strategy("test-inclusive", args=("skip-unless-schedules",))(Alias)
+register_strategy("test-verify", args=("skip-unless-schedules",))(Alias)
+register_strategy("upload-symbols", args=("never",))(Alias)
+register_strategy("reprocess-symbols", args=("never",))(Alias)
+
+
+# Strategy overrides used to tweak the default strategies. These are referenced
+# by the `optimize_strategies` parameter.
+
+
+class project:
+    """Strategies that should be applied per-project."""
+
+    autoland = {
+        "test": Any(
+            # This `Any` strategy implements bi-modal behaviour. It allows different
+            # strategies on expanded pushes vs regular pushes.
+            # This first `All` handles "expanded" pushes.
+            All(
+                # There are three substrategies in this `All`, the first two act as barriers
+                # that help determine when to apply the third:
+                # 1. On backstop pushes, `skip-unless-backstop` returns False. Therefore
+                #    the overall composite strategy is False and we don't optimize.
+                # 2. On regular pushes, `Not('skip-unless-expanded')` returns False. Therefore
+                #    the overall composite strategy is False and we don't optimize.
+                # 3. On expanded pushes, the third strategy will determine whether or
+                #    not to optimize each individual task.
+                # The barrier strategies.
+                "skip-unless-backstop",
+                Not("skip-unless-expanded"),
+                # The actual test strategy applied to "expanded" pushes.
+                Any(
+                    "skip-unless-schedules",
+                    "bugbug-reduced-manifests-fallback-last-10-pushes",
+                    "platform-disperse",
+                    split_args=split_bugbug_arg,
+                ),
+            ),
+            # This second `All` handles regular (aka not expanded or backstop)
+            # pushes.
+            All(
+                # There are two substrategies in this `All`, the first acts as a barrier
+                # that determines when to apply the second:
+                # 1. On expanded pushes (which includes backstops), `skip-unless-expanded`
+                #    returns False. Therefore the overall composite strategy is False and we
+                #    don't optimize.
+                # 2. On regular pushes, the second strategy will determine whether or
+                #    not to optimize each individual task.
+                # The barrier strategy.
+                "skip-unless-expanded",
+                # The actual test strategy applied to regular pushes.
+                Any(
+                    "skip-unless-schedules",
+                    "bugbug-reduced-manifests-fallback-low",
+                    "platform-disperse",
+                    split_args=split_bugbug_arg,
+                ),
+            ),
+        ),
+        "build": All(
+            "skip-unless-expanded",
+            Any(
+                "skip-unless-schedules",
+                "bugbug-reduced-fallback",
+                split_args=split_bugbug_arg,
+            ),
+        ),
+    }
+    """Strategy overrides that apply to autoland."""
+
+
+class experimental:
+    """Experimental strategies either under development or used as benchmarks.
+
+    These run as "shadow-schedulers" on each autoland push (tier 3) and/or can be used
+    with `./mach try auto`.  E.g:
+
+        ./mach try auto --strategy relevant_tests
+    """
+
+    bugbug_tasks_medium = {
+        "test": Any(
+            "skip-unless-schedules", "bugbug-tasks-medium", split_args=split_bugbug_arg
+        ),
+    }
+    """Doesn't limit platforms, medium confidence threshold."""
+
+    bugbug_tasks_high = {
+        "test": Any(
+            "skip-unless-schedules", "bugbug-tasks-high", split_args=split_bugbug_arg
+        ),
+    }
+    """Doesn't limit platforms, high confidence threshold."""
+
+    bugbug_debug_disperse = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-low",
+            "platform-debug",
+            "platform-disperse",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Restricts tests to debug platforms."""
+
+    bugbug_disperse_low = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-low",
+            "platform-disperse",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms, low confidence threshold."""
+
+    bugbug_disperse_medium = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-medium",
+            "platform-disperse",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms, medium confidence threshold."""
+
+    bugbug_disperse_reduced_medium = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-reduced-manifests",
+            "platform-disperse",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms, medium confidence threshold with reduced tasks."""
+
+    bugbug_reduced_manifests_config_selection_low = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-reduced-manifests-config-selection-low",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Choose configs selected by bugbug, low confidence threshold with reduced tasks."""
+
+    bugbug_reduced_manifests_config_selection_medium = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-reduced-manifests-config-selection",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Choose configs selected by bugbug, medium confidence threshold with reduced tasks."""
+
+    bugbug_disperse_medium_no_unseen = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-medium",
+            "platform-disperse-no-unseen",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms (no modified for unseen configurations), medium confidence
+    threshold."""
+
+    bugbug_disperse_medium_only_one = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-medium",
+            "platform-disperse-only-one",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms (one platform per group), medium confidence threshold."""
+
+    bugbug_disperse_high = {
+        "test": Any(
+            "skip-unless-schedules",
+            "bugbug-high",
+            "platform-disperse",
+            split_args=split_bugbug_arg,
+        ),
+    }
+    """Disperse tests across platforms, high confidence threshold."""
+
+    bugbug_reduced = {
+        "test": Any(
+            "skip-unless-schedules", "bugbug-reduced", split_args=split_bugbug_arg
+        ),
+    }
+    """Use the reduced set of tasks (and no groups) chosen by bugbug."""
+
+    bugbug_reduced_high = {
+        "test": Any(
+            "skip-unless-schedules", "bugbug-reduced-high", split_args=split_bugbug_arg
+        ),
+    }
+    """Use the reduced set of tasks (and no groups) chosen by bugbug, high
+    confidence threshold."""
+
+    relevant_tests = {
+        "test": Any("skip-unless-schedules", "skip-unless-has-relevant-tests"),
+    }
+    """Runs task containing tests in the same directories as modified files."""
+
+
+class ExperimentalOverride:
+    """Overrides dictionaries that are stored in a container with new values.
+
+    This can be used to modify all strategies in a collection the same way,
+    presumably with strategies affecting kinds of tasks tangential to the
+    current context.
+
+    Args:
+        base (object): A container class supporting attribute access.
+        overrides (dict): Values to update any accessed dictionaries with.
+    """
+
+    def __init__(self, base, overrides):
+        self.base = base
+        self.overrides = overrides
+
+    def __getattr__(self, name):
+        val = getattr(self.base, name).copy()
+        for name, strategy in self.overrides.items():
+            if isinstance(strategy, str) and strategy.startswith("base:"):
+                strategy = val[strategy[len("base:") :]]
+
+            val[name] = strategy
+        return val
+
+
+tryselect = ExperimentalOverride(
+    experimental,
+    {
+        "build": Any(
+            "skip-unless-schedules", "bugbug-reduced", split_args=split_bugbug_arg
+        ),
+        "test-verify": "base:test",
+        "upload-symbols": Alias("always"),
+        "reprocess-symbols": Alias("always"),
+    },
+)
diff --git a/taskcluster/gecko_taskgraph/optimize/backstop.py b/taskcluster/gecko_taskgraph/optimize/backstop.py
new file mode 100644
index 0000000000..7b0c86222b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/optimize/backstop.py
@@ -0,0 +1,47 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.optimize.base import All, OptimizationStrategy, register_strategy
+
+from gecko_taskgraph.util.backstop import BACKSTOP_PUSH_INTERVAL
+
+
+@register_strategy("skip-unless-backstop")
+class SkipUnlessBackstop(OptimizationStrategy):
+    """Always removes tasks except on backstop pushes."""
+
+    def should_remove_task(self, task, params, _):
+        return not params["backstop"]
+
+
+class SkipUnlessPushInterval(OptimizationStrategy):
+    """Always removes tasks except every N pushes.
+
+    Args:
+        push_interval (int): Number of pushes
+    """
+
+    def __init__(self, push_interval, remove_on_projects=None):
+        self.push_interval = push_interval
+
+    @property
+    def description(self):
+        return f"skip-unless-push-interval-{self.push_interval}"
+
+    def should_remove_task(self, task, params, _):
+        # On every Nth push, want to run all tasks.
+        return int(params["pushlog_id"]) % self.push_interval != 0
+
+
+# Strategy to run tasks on "expanded" pushes, currently defined as pushes that
+# are half the backstop interval. The 'All' composite strategy means that the
+# "backstop" strategy will prevent "expanded" from applying on backstop pushes.
+register_strategy(
+    "skip-unless-expanded",
+    args=(
+        "skip-unless-backstop",
+        SkipUnlessPushInterval(BACKSTOP_PUSH_INTERVAL / 2),
+    ),
+)(All)
diff --git a/taskcluster/gecko_taskgraph/optimize/bugbug.py b/taskcluster/gecko_taskgraph/optimize/bugbug.py
new file mode 100644
index 0000000000..d8603560ef
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/optimize/bugbug.py
@@ -0,0 +1,321 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from collections import defaultdict
+from fnmatch import fnmatch
+
+from taskgraph.optimize.base import OptimizationStrategy, register_strategy, registry
+
+from gecko_taskgraph.util.bugbug import (
+    CT_HIGH,
+    CT_LOW,
+    CT_MEDIUM,
+    BugbugTimeoutException,
+    push_schedules,
+)
+from gecko_taskgraph.util.hg import get_push_data
+
+FALLBACK = "skip-unless-has-relevant-tests"
+
+
+def merge_bugbug_replies(data, new_data):
+    """Merge a bugbug reply (stored in the `new_data` argument) into another (stored
+    in the `data` argument).
+    """
+    for key, value in new_data.items():
+        if isinstance(value, dict):
+            if key not in data:
+                data[key] = {}
+
+            if len(value) == 0:
+                continue
+
+            dict_value = next(iter(value.values()))
+            if isinstance(dict_value, list):
+                for name, configs in value.items():
+                    if name not in data[key]:
+                        data[key][name] = set()
+
+                    data[key][name].update(configs)
+            else:
+                for name, confidence in value.items():
+                    if name not in data[key] or data[key][name] < confidence:
+                        data[key][name] = confidence
+        elif isinstance(value, list):
+            if key not in data:
+                data[key] = set()
+
+            data[key].update(value)
+
+
+@register_strategy("bugbug-low", args=(CT_LOW,))
+@register_strategy("bugbug-medium", args=(CT_MEDIUM,))
+@register_strategy("bugbug-high", args=(CT_HIGH,))
+@register_strategy("bugbug-tasks-medium", args=(CT_MEDIUM, True))
+@register_strategy("bugbug-tasks-high", args=(CT_HIGH, True))
+@register_strategy("bugbug-reduced", args=(CT_MEDIUM, True, True))
+@register_strategy("bugbug-reduced-fallback", args=(CT_MEDIUM, True, True, FALLBACK))
+@register_strategy("bugbug-reduced-high", args=(CT_HIGH, True, True))
+@register_strategy("bugbug-reduced-manifests", args=(CT_MEDIUM, False, True))
+@register_strategy(
+    "bugbug-reduced-manifests-config-selection-low",
+    args=(CT_LOW, False, True, None, 1, True),
+)
+@register_strategy(
+    "bugbug-reduced-manifests-config-selection",
+    args=(CT_MEDIUM, False, True, None, 1, True),
+)
+@register_strategy(
+    "bugbug-reduced-manifests-fallback-low", args=(CT_LOW, False, True, FALLBACK)
+)
+@register_strategy(
+    "bugbug-reduced-manifests-fallback", args=(CT_MEDIUM, False, True, FALLBACK)
+)
+@register_strategy(
+    "bugbug-reduced-manifests-fallback-last-10-pushes",
+    args=(0.3, False, True, FALLBACK, 10),
+)
+class BugBugPushSchedules(OptimizationStrategy):
+    """Query the 'bugbug' service to retrieve relevant tasks and manifests.
+
+    Args:
+        confidence_threshold (float): The minimum confidence threshold (in
+            range [0, 1]) needed for a task to be scheduled.
+        tasks_only (bool): Whether or not to only use tasks and no groups
+            (default: False)
+        use_reduced_tasks (bool): Whether or not to use the reduced set of tasks
+            provided by the bugbug service (default: False).
+        fallback (str): The fallback strategy to use if there
+            was a failure in bugbug (default: None)
+        num_pushes (int): The number of pushes to consider for the selection
+            (default: 1).
+        select_configs (bool): Whether to select configurations for manifests
+            too (default: False).
+    """
+
+    def __init__(
+        self,
+        confidence_threshold,
+        tasks_only=False,
+        use_reduced_tasks=False,
+        fallback=None,
+        num_pushes=1,
+        select_configs=False,
+    ):
+        self.confidence_threshold = confidence_threshold
+        self.use_reduced_tasks = use_reduced_tasks
+        self.fallback = fallback
+        self.tasks_only = tasks_only
+        self.num_pushes = num_pushes
+        self.select_configs = select_configs
+        self.timedout = False
+
+    def should_remove_task(self, task, params, importance):
+        project = params["project"]
+
+        if project not in ("autoland", "try"):
+            return False
+
+        current_push_id = int(params["pushlog_id"])
+
+        rev = params["head_rev"]
+
+        if self.timedout:
+            return registry[self.fallback].should_remove_task(task, params, importance)
+
+        data = {}
+
+        start_push_id = current_push_id - self.num_pushes + 1
+        if self.num_pushes != 1:
+            push_data = get_push_data(
+                params["head_repository"], project, start_push_id, current_push_id - 1
+            )
+
+        for push_id in range(start_push_id, current_push_id + 1):
+            if push_id == current_push_id:
+                rev = params["head_rev"]
+            else:
+                rev = push_data[push_id]["changesets"][-1]
+
+            try:
+                new_data = push_schedules(params["project"], rev)
+                merge_bugbug_replies(data, new_data)
+            except BugbugTimeoutException:
+                if not self.fallback:
+                    raise
+
+                self.timedout = True
+                return self.should_remove_task(task, params, importance)
+
+        key = "reduced_tasks" if self.use_reduced_tasks else "tasks"
+        tasks = {
+            task
+            for task, confidence in data.get(key, {}).items()
+            if confidence >= self.confidence_threshold
+        }
+
+        test_manifests = task.attributes.get("test_manifests")
+        if test_manifests is None or self.tasks_only:
+            if data.get("known_tasks") and task.label not in data["known_tasks"]:
+                return False
+
+            if task.label not in tasks:
+                return True
+
+            return False
+
+        # If a task contains more than one group, use the max confidence.
+        groups = data.get("groups", {})
+        confidences = [c for g, c in groups.items() if g in test_manifests]
+        if not confidences or max(confidences) < self.confidence_threshold:
+            return True
+
+        # If the task configuration doesn't match the ones selected by bugbug for
+        # the manifests, optimize out.
+        if self.select_configs:
+            selected_groups = [
+                g
+                for g, c in groups.items()
+                if g in test_manifests and c > self.confidence_threshold
+            ]
+
+            config_groups = data.get("config_groups", defaultdict(list))
+
+            # Configurations returned by bugbug are in a format such as
+            # `test-windows10-64/opt-*-e10s`, while task labels are like
+            # test-windows10-64-qr/opt-mochitest-browser-chrome-e10s-6.
+            # In order to match the strings, we need to ignore the chunk number
+            # from the task label.
+            parts = task.label.split("-")
+            label_without_chunk_number = "-".join(
+                parts[:-1] if parts[-1].isdigit() else parts
+            )
+
+            if not any(
+                fnmatch(label_without_chunk_number, config)
+                for group in selected_groups
+                for config in config_groups[group]
+            ):
+                return True
+
+        # Store group importance so future optimizers can access it.
+        for manifest in test_manifests:
+            if manifest not in groups:
+                continue
+
+            confidence = groups[manifest]
+            if confidence >= CT_HIGH:
+                importance[manifest] = "high"
+            elif confidence >= CT_MEDIUM:
+                importance[manifest] = "medium"
+            elif confidence >= CT_LOW:
+                importance[manifest] = "low"
+            else:
+                importance[manifest] = "lowest"
+
+        return False
+
+
+@register_strategy("platform-debug")
+class SkipUnlessDebug(OptimizationStrategy):
+    """Only run debug platforms."""
+
+    def should_remove_task(self, task, params, arg):
+        return (
+            "build_type" in task.attributes and task.attributes["build_type"] != "debug"
+        )
+
+
+@register_strategy("platform-disperse")
+@register_strategy("platform-disperse-no-unseen", args=(None, 0))
+@register_strategy(
+    "platform-disperse-only-one",
+    args=(
+        {
+            "high": 1,
+            "medium": 1,
+            "low": 1,
+            "lowest": 0,
+        },
+        0,
+    ),
+)
+class DisperseGroups(OptimizationStrategy):
+    """Disperse groups across test configs.
+
+    Each task has an associated 'importance' dict passed in via the arg. This
+    is of the form `{<group>: <importance>}`.
+
+    Where 'group' is a test group id (usually a path to a manifest), and 'importance' is
+    one of `{'lowest', 'low', 'medium', 'high'}`.
+
+    Each importance value has an associated 'count' as defined in
+    `self.target_counts`. It guarantees that 'manifest' will run in at least
+    'count' different configurations (assuming there are enough tasks
+    containing 'manifest').
+
+    On configurations that haven't been seen before, we'll increase the target
+    count by `self.unseen_modifier` to increase the likelihood of scheduling a
+    task on that configuration.
+
+    Args:
+        target_counts (dict): Override DEFAULT_TARGET_COUNTS with custom counts. This
+            is a dict mapping the importance value ('lowest', 'low', etc) to the
+            minimum number of configurations manifests with this value should run
+            on.
+
+        unseen_modifier (int): Override DEFAULT_UNSEEN_MODIFIER to a custom
+            value. This is the amount we'll increase 'target_count' by for unseen
+            configurations.
+    """
+
+    DEFAULT_TARGET_COUNTS = {
+        "high": 3,
+        "medium": 2,
+        "low": 1,
+        "lowest": 0,
+    }
+    DEFAULT_UNSEEN_MODIFIER = 1
+
+    def __init__(self, target_counts=None, unseen_modifier=DEFAULT_UNSEEN_MODIFIER):
+        self.target_counts = self.DEFAULT_TARGET_COUNTS.copy()
+        if target_counts:
+            self.target_counts.update(target_counts)
+        self.unseen_modifier = unseen_modifier
+
+        self.count = defaultdict(int)
+        self.seen_configurations = set()
+
+    def should_remove_task(self, task, params, importance):
+        test_manifests = task.attributes.get("test_manifests")
+        test_platform = task.attributes.get("test_platform")
+
+        if not importance or not test_manifests or not test_platform:
+            return False
+
+        # Build the test configuration key.
+        key = test_platform
+        if "unittest_variant" in task.attributes:
+            key += "-" + task.attributes["unittest_variant"]
+
+        important_manifests = set(test_manifests) & set(importance)
+        for manifest in important_manifests:
+            target_count = self.target_counts[importance[manifest]]
+
+            # If this configuration hasn't been seen before, increase the
+            # likelihood of scheduling the task.
+            if key not in self.seen_configurations:
+                target_count += self.unseen_modifier
+
+            if self.count[manifest] < target_count:
+                # Update manifest counts and seen configurations.
+                self.seen_configurations.add(key)
+                for manifest in important_manifests:
+                    self.count[manifest] += 1
+                return False
+
+        # Should remove task because all manifests have reached their
+        # importance count (or there were no important manifests).
+        return True
diff --git a/taskcluster/gecko_taskgraph/optimize/schema.py b/taskcluster/gecko_taskgraph/optimize/schema.py
new file mode 100644
index 0000000000..a7f878cf60
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/optimize/schema.py
@@ -0,0 +1,60 @@
+#  This Source Code Form is subject to the terms of the Mozilla Public
+#  License, v. 2.0. If a copy of the MPL was not distributed with this
+#  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+import voluptuous
+from mozbuild import schedules
+
+logger = logging.getLogger(__name__)
+
+
+default_optimizations = (
+    # always run this task (default)
+    None,
+    # always optimize this task
+    {"always": None},
+    # optimize strategy aliases for build kind
+    {"build": list(schedules.ALL_COMPONENTS)},
+    # search the index for the given index namespaces, and replace this task if found
+    # the search occurs in order, with the first match winning
+    {"index-search": [str]},
+    # never optimize this task
+    {"never": None},
+    # skip the task except for every Nth push
+    {"skip-unless-expanded": None},
+    {"skip-unless-backstop": None},
+    # skip this task if none of the given file patterns match
+    {"skip-unless-changed": [str]},
+    # skip this task if unless the change files' SCHEDULES contains any of these components
+    {"skip-unless-schedules": list(schedules.ALL_COMPONENTS)},
+    # optimize strategy aliases for the test kind
+    {"test": list(schedules.ALL_COMPONENTS)},
+    {"test-inclusive": list(schedules.ALL_COMPONENTS)},
+    # optimize strategy alias for test-verify tasks
+    {"test-verify": list(schedules.ALL_COMPONENTS)},
+    # optimize strategy alias for upload-symbols tasks
+    {"upload-symbols": None},
+    # optimize strategy alias for reprocess-symbols tasks
+    {"reprocess-symbols": None},
+)
+
+OptimizationSchema = voluptuous.Any(*default_optimizations)
+
+
+def set_optimization_schema(schema_tuple):
+    """Sets OptimizationSchema so it can be imported by the task transform.
+    This function is called by projects that extend Firefox's taskgraph.
+    It should be called by the project's taskgraph:register function before
+    any transport or job runner code is imported.
+
+    :param tuple schema_tuple: Tuple of possible optimization strategies
+    """
+    global OptimizationSchema
+    if OptimizationSchema.validators == default_optimizations:
+        logger.info("OptimizationSchema updated.")
+        OptimizationSchema = voluptuous.Any(*schema_tuple)
+    else:
+        raise Exception("Can only call set_optimization_schema once.")
diff --git a/taskcluster/gecko_taskgraph/optimize/strategies.py b/taskcluster/gecko_taskgraph/optimize/strategies.py
new file mode 100644
index 0000000000..2e520c4750
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/optimize/strategies.py
@@ -0,0 +1,136 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+from datetime import datetime
+
+import mozpack.path as mozpath
+from mozbuild.base import MozbuildObject
+from mozbuild.util import memoize
+from taskgraph.optimize.base import OptimizationStrategy, register_strategy
+from taskgraph.util.taskcluster import find_task_id
+
+from gecko_taskgraph import files_changed
+from gecko_taskgraph.util.taskcluster import status_task
+
+logger = logging.getLogger(__name__)
+
+
+@register_strategy("index-search")
+class IndexSearch(OptimizationStrategy):
+
+    # A task with no dependencies remaining after optimization will be replaced
+    # if artifacts exist for the corresponding index_paths.
+    # Otherwise, we're in one of the following cases:
+    # - the task has un-optimized dependencies
+    # - the artifacts have expired
+    # - some changes altered the index_paths and new artifacts need to be
+    # created.
+    # In every of those cases, we need to run the task to create or refresh
+    # artifacts.
+
+    fmt = "%Y-%m-%dT%H:%M:%S.%fZ"
+
+    def should_replace_task(self, task, params, deadline, index_paths):
+        "Look for a task with one of the given index paths"
+        for index_path in index_paths:
+            try:
+                task_id = find_task_id(index_path)
+                status = status_task(task_id)
+                # status can be `None` if we're in `testing` mode
+                # (e.g. test-action-callback)
+                if not status or status.get("state") in ("exception", "failed"):
+                    continue
+
+                if deadline and datetime.strptime(
+                    status["expires"], self.fmt
+                ) < datetime.strptime(deadline, self.fmt):
+                    continue
+
+                return task_id
+            except KeyError:
+                # 404 will end up here and go on to the next index path
+                pass
+
+        return False
+
+
+@register_strategy("skip-unless-changed")
+class SkipUnlessChanged(OptimizationStrategy):
+    def should_remove_task(self, task, params, file_patterns):
+        # pushlog_id == -1 - this is the case when run from a cron.yml job
+        if params.get("pushlog_id") == -1:
+            return False
+
+        changed = files_changed.check(params, file_patterns)
+        if not changed:
+            logger.debug(
+                "no files found matching a pattern in `skip-unless-changed` for "
+                + task.label
+            )
+            return True
+        return False
+
+
+@register_strategy("skip-unless-schedules")
+class SkipUnlessSchedules(OptimizationStrategy):
+    @memoize
+    def scheduled_by_push(self, repository, revision):
+        changed_files = files_changed.get_changed_files(repository, revision)
+
+        mbo = MozbuildObject.from_environment()
+        # the decision task has a sparse checkout, so, mozbuild_reader will use
+        # a MercurialRevisionFinder with revision '.', which should be the same
+        # as `revision`; in other circumstances, it will use a default reader
+        rdr = mbo.mozbuild_reader(config_mode="empty")
+
+        components = set()
+        for p, m in rdr.files_info(changed_files).items():
+            components |= set(m["SCHEDULES"].components)
+
+        return components
+
+    def should_remove_task(self, task, params, conditions):
+        if params.get("pushlog_id") == -1:
+            return False
+
+        scheduled = self.scheduled_by_push(
+            params["head_repository"], params["head_rev"]
+        )
+        conditions = set(conditions)
+        # if *any* of the condition components are scheduled, do not optimize
+        if conditions & scheduled:
+            return False
+
+        return True
+
+
+@register_strategy("skip-unless-has-relevant-tests")
+class SkipUnlessHasRelevantTests(OptimizationStrategy):
+    """Optimizes tasks that don't run any tests that were
+    in child directories of a modified file.
+    """
+
+    @memoize
+    def get_changed_dirs(self, repo, rev):
+        changed = map(mozpath.dirname, files_changed.get_changed_files(repo, rev))
+        # Filter out empty directories (from files modified in the root).
+        # Otherwise all tasks would be scheduled.
+        return {d for d in changed if d}
+
+    def should_remove_task(self, task, params, _):
+        if not task.attributes.get("test_manifests"):
+            return True
+
+        for d in self.get_changed_dirs(params["head_repository"], params["head_rev"]):
+            for t in task.attributes["test_manifests"]:
+                if t.startswith(d):
+                    logger.debug(
+                        "{} runs a test path ({}) contained by a modified file ({})".format(
+                            task.label, t, d
+                        )
+                    )
+                    return False
+        return True
diff --git a/taskcluster/gecko_taskgraph/parameters.py b/taskcluster/gecko_taskgraph/parameters.py
new file mode 100644
index 0000000000..e7e5df4605
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/parameters.py
@@ -0,0 +1,100 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import logging
+import os
+
+from taskgraph.parameters import extend_parameters_schema
+from voluptuous import Any, Required
+
+from gecko_taskgraph import GECKO
+
+logger = logging.getLogger(__name__)
+
+
+gecko_parameters_schema = {
+    Required("app_version"): str,
+    Required("backstop"): bool,
+    Required("build_number"): int,
+    Required("enable_always_target"): bool,
+    Required("hg_branch"): str,
+    Required("message"): str,
+    Required("next_version"): Any(None, str),
+    Required("optimize_strategies"): Any(None, str),
+    Required("phabricator_diff"): Any(None, str),
+    Required("release_enable_emefree"): bool,
+    Required("release_enable_partner_repack"): bool,
+    Required("release_enable_partner_attribution"): bool,
+    Required("release_eta"): Any(None, str),
+    Required("release_history"): {str: dict},
+    Required("release_partners"): Any(None, [str]),
+    Required("release_partner_config"): Any(None, dict),
+    Required("release_partner_build_number"): int,
+    Required("release_type"): str,
+    Required("release_product"): Any(None, str),
+    Required("required_signoffs"): [str],
+    Required("signoff_urls"): dict,
+    Required("test_manifest_loader"): str,
+    Required("try_mode"): Any(None, str),
+    Required("try_options"): Any(None, dict),
+    Required("try_task_config"): dict,
+    Required("version"): str,
+}
+
+
+def get_contents(path):
+    with open(path, "r") as fh:
+        contents = fh.readline().rstrip()
+    return contents
+
+
+def get_version(product_dir="browser"):
+    version_path = os.path.join(GECKO, product_dir, "config", "version_display.txt")
+    return get_contents(version_path)
+
+
+def get_app_version(product_dir="browser"):
+    app_version_path = os.path.join(GECKO, product_dir, "config", "version.txt")
+    return get_contents(app_version_path)
+
+
+def get_defaults(repo_root=None):
+    return {
+        "app_version": get_app_version(),
+        "backstop": False,
+        "base_repository": "https://hg.mozilla.org/mozilla-unified",
+        "build_number": 1,
+        "enable_always_target": False,
+        "head_repository": "https://hg.mozilla.org/mozilla-central",
+        "hg_branch": "default",
+        "message": "",
+        "next_version": None,
+        "optimize_strategies": None,
+        "phabricator_diff": None,
+        "project": "mozilla-central",
+        "release_enable_emefree": False,
+        "release_enable_partner_repack": False,
+        "release_enable_partner_attribution": False,
+        "release_eta": "",
+        "release_history": {},
+        "release_partners": [],
+        "release_partner_config": None,
+        "release_partner_build_number": 1,
+        "release_product": None,
+        "release_type": "nightly",
+        # This refers to the upstream repo rather than the local checkout, so
+        # should be hardcoded to 'hg' even with git-cinnabar.
+        "repository_type": "hg",
+        "required_signoffs": [],
+        "signoff_urls": {},
+        "test_manifest_loader": "default",
+        "try_mode": None,
+        "try_options": None,
+        "try_task_config": {},
+        "version": get_version(),
+    }
+
+
+def register_parameters():
+    extend_parameters_schema(gecko_parameters_schema, defaults_fn=get_defaults)
diff --git a/taskcluster/gecko_taskgraph/target_tasks.py b/taskcluster/gecko_taskgraph/target_tasks.py
new file mode 100644
index 0000000000..90ebd479ad
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/target_tasks.py
@@ -0,0 +1,1497 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import itertools
+import os
+import re
+from datetime import datetime, timedelta
+
+from redo import retry
+from taskgraph.parameters import Parameters
+from taskgraph.target_tasks import _target_task, get_method
+from taskgraph.util.taskcluster import find_task_id
+
+from gecko_taskgraph import GECKO, try_option_syntax
+from gecko_taskgraph.util.attributes import (
+    match_run_on_hg_branches,
+    match_run_on_projects,
+)
+from gecko_taskgraph.util.hg import find_hg_revision_push_info, get_hg_commit_message
+from gecko_taskgraph.util.platforms import platform_family
+
+# Some tasks show up in the target task set, but are possibly special cases,
+# uncommon tasks, or tasks running against limited hardware set that they
+# should only be selectable with --full.
+UNCOMMON_TRY_TASK_LABELS = [
+    # Platforms and/or Build types
+    r"build-.*-gcp",  # Bug 1631990
+    r"mingwclang",  # Bug 1631990
+    r"valgrind",  # Bug 1631990
+    # Android tasks
+    r"android-geckoview-docs",
+    r"android-hw",
+    # Windows tasks
+    r"windows10-64-ref-hw",
+    r"windows10-aarch64-qr",
+    # Linux tasks
+    r"linux-",  # hide all linux32 tasks by default - bug 1599197
+    r"linux1804-32",  # hide linux32 tests - bug 1599197
+    # Test tasks
+    r"web-platform-tests.*backlog",  # hide wpt jobs that are not implemented yet - bug 1572820
+    r"-ccov",
+    r"-profiling-",  # talos/raptor profiling jobs are run too often
+    # Hide shippable versions of tests we have opt versions of because the non-shippable
+    # versions are faster to run. This is mostly perf tests.
+    r"-shippable(?!.*(awsy|browsertime|marionette-headless|mochitest-devtools-chrome-fis|raptor|talos|web-platform-tests-wdspec-headless|mochitest-plain-headless))",  # noqa - too long
+]
+
+
+def index_exists(index_path, reason=""):
+    print(f"Looking for existing index {index_path} {reason}...")
+    try:
+        task_id = find_task_id(index_path)
+        print(f"Index {index_path} exists: taskId {task_id}")
+        return True
+    except KeyError:
+        print(f"Index {index_path} doesn't exist.")
+        return False
+
+
+def filter_out_shipping_phase(task, parameters):
+    return (
+        # nightly still here because of geckodriver
+        not task.attributes.get("nightly")
+        and task.attributes.get("shipping_phase") in (None, "build")
+    )
+
+
+def filter_out_devedition(task, parameters):
+    return not task.attributes.get("shipping_product") == "devedition"
+
+
+def filter_out_cron(task, parameters):
+    """
+    Filter out tasks that run via cron.
+    """
+    return not task.attributes.get("cron")
+
+
+def filter_for_project(task, parameters):
+    """Filter tasks by project.  Optionally enable nightlies."""
+    run_on_projects = set(task.attributes.get("run_on_projects", []))
+    return match_run_on_projects(parameters["project"], run_on_projects)
+
+
+def filter_for_hg_branch(task, parameters):
+    """Filter tasks by hg branch.
+    If `run_on_hg_branch` is not defined, then task runs on all branches"""
+    run_on_hg_branches = set(task.attributes.get("run_on_hg_branches", ["all"]))
+    return match_run_on_hg_branches(parameters["hg_branch"], run_on_hg_branches)
+
+
+def filter_on_platforms(task, platforms):
+    """Filter tasks on the given platform"""
+    platform = task.attributes.get("build_platform")
+    return platform in platforms
+
+
+def filter_by_uncommon_try_tasks(task, optional_filters=None):
+    """Filters tasks that should not be commonly run on try.
+
+    Args:
+        task (str): String representing the task name.
+        optional_filters (list, optional):
+            Additional filters to apply to task filtering.
+
+    Returns:
+        (Boolean): True if task does not match any known filters.
+            False otherwise.
+    """
+    filters = UNCOMMON_TRY_TASK_LABELS
+    if optional_filters:
+        filters = itertools.chain(filters, optional_filters)
+
+    return not any(re.search(pattern, task) for pattern in filters)
+
+
+def filter_by_regex(task_label, regexes, mode="include"):
+    """Filters tasks according to a list of pre-compiled reguar expressions.
+
+    If mode is "include", a task label must match any regex to pass.
+    If it is "exclude", a task label must _not_ match any regex to pass.
+    """
+    if not regexes:
+        return True
+
+    assert mode in ["include", "exclude"]
+
+    any_match = any(r.search(task_label) for r in regexes)
+    if any_match:
+        return mode == "include"
+    return mode != "include"
+
+
+def filter_release_tasks(task, parameters):
+    platform = task.attributes.get("build_platform")
+    if platform in (
+        "linux",
+        "linux64",
+        "macosx64",
+        "win32",
+        "win64",
+        "win64-aarch64",
+    ):
+        if task.attributes["kind"] == "l10n":
+            # This is on-change l10n
+            return True
+        if (
+            task.attributes["build_type"] == "opt"
+            and task.attributes.get("unittest_suite") != "talos"
+            and task.attributes.get("unittest_suite") != "raptor"
+        ):
+            return False
+
+    if task.attributes.get("shipping_phase") not in (None, "build"):
+        return False
+
+    """ No debug on release, keep on ESR with 4 week cycles, release
+    will not be too different from central, but ESR will live for a long time.
+
+    From June 2019 -> June 2020, we found 1 unique regression on ESR debug
+    and 5 unique regressions on beta/release.  Keeping spidermonkey and linux
+    debug finds all but 1 unique regressions (windows found on try) for beta/release.
+
+    ...but debug-only failures started showing up on ESR (esr-91, esr-102) so
+    desktop debug tests were added back for beta.
+    """
+    build_type = task.attributes.get("build_type", "")
+    build_platform = task.attributes.get("build_platform", "")
+    test_platform = task.attributes.get("test_platform", "")
+
+    if parameters["release_type"].startswith("esr") or (
+        parameters["release_type"] == "beta" and "android" not in build_platform
+    ):
+        return True
+
+    # code below here is intended to reduce release debug tasks
+    if task.kind == "hazard" or "toolchain" in build_platform:
+        # keep hazard and toolchain builds around
+        return True
+
+    if build_type == "debug":
+        if "linux" not in build_platform:
+            # filter out windows/mac/android
+            return False
+        if task.kind not in ["spidermonkey"] and "-qr" in test_platform:
+            # filter out linux-qr tests, leave spidermonkey
+            return False
+        if "64" not in build_platform:
+            # filter out linux32 builds
+            return False
+
+    # webrender-android-*-debug doesn't have attributes to find 'debug', using task.label.
+    if task.kind == "webrender" and "debug" in task.label:
+        return False
+    return True
+
+
+def filter_out_missing_signoffs(task, parameters):
+    for signoff in parameters["required_signoffs"]:
+        if signoff not in parameters["signoff_urls"] and signoff in task.attributes.get(
+            "required_signoffs", []
+        ):
+            return False
+    return True
+
+
+def filter_tests_without_manifests(task, parameters):
+    """Remove test tasks that have an empty 'test_manifests' attribute.
+
+    This situation can arise when the test loader (e.g bugbug) decided there
+    weren't any important manifests to run for the given push. We filter tasks
+    out here rather than in the transforms so that the full task graph is still
+    aware that the task exists (which is needed by the backfill action).
+    """
+    if (
+        task.kind == "test"
+        and "test_manifests" in task.attributes
+        and not task.attributes["test_manifests"]
+    ):
+        return False
+    return True
+
+
+def standard_filter(task, parameters):
+    return all(
+        filter_func(task, parameters)
+        for filter_func in (
+            filter_out_cron,
+            filter_for_project,
+            filter_for_hg_branch,
+            filter_tests_without_manifests,
+        )
+    )
+
+
+def accept_raptor_android_build(platform):
+    """Helper function for selecting the correct android raptor builds."""
+    if "android" not in platform:
+        return False
+    if "shippable" not in platform:
+        return False
+    if "p2" in platform and "aarch64" in platform:
+        return False
+    if "p5" in platform and "aarch64" in platform:
+        return False
+    if "g5" in platform:
+        return False
+    if "a51" in platform:
+        return True
+
+
+def filter_unsupported_artifact_builds(task, parameters):
+    try_config = parameters.get("try_task_config", {})
+    if not try_config.get("use-artifact-builds", False):
+        return True
+
+    supports_artifact_builds = task.attributes.get("supports-artifact-builds", True)
+    return supports_artifact_builds
+
+
+def filter_out_shippable(task):
+    return not task.attributes.get("shippable", False)
+
+
+def _try_task_config(full_task_graph, parameters, graph_config):
+    requested_tasks = parameters["try_task_config"]["tasks"]
+    return list(set(requested_tasks) & full_task_graph.graph.nodes)
+
+
+def _try_option_syntax(full_task_graph, parameters, graph_config):
+    """Generate a list of target tasks based on try syntax in
+    parameters['message'] and, for context, the full task graph."""
+    options = try_option_syntax.TryOptionSyntax(
+        parameters, full_task_graph, graph_config
+    )
+    target_tasks_labels = [
+        t.label
+        for t in full_task_graph.tasks.values()
+        if options.task_matches(t)
+        and filter_by_uncommon_try_tasks(t.label)
+        and filter_unsupported_artifact_builds(t, parameters)
+    ]
+
+    attributes = {
+        k: getattr(options, k)
+        for k in [
+            "no_retry",
+            "tag",
+        ]
+    }
+
+    for l in target_tasks_labels:
+        task = full_task_graph[l]
+        if "unittest_suite" in task.attributes:
+            task.attributes["task_duplicates"] = options.trigger_tests
+
+    for l in target_tasks_labels:
+        task = full_task_graph[l]
+        # If the developer wants test jobs to be rebuilt N times we add that value here
+        if options.trigger_tests > 1 and "unittest_suite" in task.attributes:
+            task.attributes["task_duplicates"] = options.trigger_tests
+
+        # If the developer wants test talos jobs to be rebuilt N times we add that value here
+        if (
+            options.talos_trigger_tests > 1
+            and task.attributes.get("unittest_suite") == "talos"
+        ):
+            task.attributes["task_duplicates"] = options.talos_trigger_tests
+
+        # If the developer wants test raptor jobs to be rebuilt N times we add that value here
+        if (
+            options.raptor_trigger_tests
+            and options.raptor_trigger_tests > 1
+            and task.attributes.get("unittest_suite") == "raptor"
+        ):
+            task.attributes["task_duplicates"] = options.raptor_trigger_tests
+
+        task.attributes.update(attributes)
+
+    # Add notifications here as well
+    if options.notifications:
+        for task in full_task_graph:
+            owner = parameters.get("owner")
+            routes = task.task.setdefault("routes", [])
+            if options.notifications == "all":
+                routes.append(f"notify.email.{owner}.on-any")
+            elif options.notifications == "failure":
+                routes.append(f"notify.email.{owner}.on-failed")
+                routes.append(f"notify.email.{owner}.on-exception")
+
+    return target_tasks_labels
+
+
+@_target_task("try_tasks")
+def target_tasks_try(full_task_graph, parameters, graph_config):
+    try_mode = parameters["try_mode"]
+    if try_mode == "try_task_config":
+        return _try_task_config(full_task_graph, parameters, graph_config)
+    if try_mode == "try_option_syntax":
+        return _try_option_syntax(full_task_graph, parameters, graph_config)
+    # With no try mode, we schedule nothing, allowing the user to add tasks
+    # later via treeherder.
+    return []
+
+
+@_target_task("try_select_tasks")
+def target_tasks_try_select(full_task_graph, parameters, graph_config):
+    tasks = target_tasks_try_select_uncommon(full_task_graph, parameters, graph_config)
+    return [l for l in tasks if filter_by_uncommon_try_tasks(l)]
+
+
+@_target_task("try_select_tasks_uncommon")
+def target_tasks_try_select_uncommon(full_task_graph, parameters, graph_config):
+    from gecko_taskgraph.decision import PER_PROJECT_PARAMETERS
+
+    projects = ("autoland", "mozilla-central")
+    if parameters["project"] not in projects:
+        projects = (parameters["project"],)
+
+    tasks = set()
+    for project in projects:
+        params = dict(parameters)
+        params["project"] = project
+        parameters = Parameters(**params)
+
+        try:
+            target_tasks_method = PER_PROJECT_PARAMETERS[project]["target_tasks_method"]
+        except KeyError:
+            target_tasks_method = "default"
+
+        tasks.update(
+            get_method(target_tasks_method)(full_task_graph, parameters, graph_config)
+        )
+
+    return sorted(tasks)
+
+
+@_target_task("try_auto")
+def target_tasks_try_auto(full_task_graph, parameters, graph_config):
+    """Target the tasks which have indicated they should be run on autoland
+    (rather than try) via the `run_on_projects` attributes.
+
+    Should do the same thing as the `default` target tasks method.
+    """
+    params = dict(parameters)
+    params["project"] = "autoland"
+    parameters = Parameters(**params)
+
+    regex_filters = parameters["try_task_config"].get("tasks-regex")
+    include_regexes = exclude_regexes = []
+    if regex_filters:
+        include_regexes = [re.compile(r) for r in regex_filters.get("include", [])]
+        exclude_regexes = [re.compile(r) for r in regex_filters.get("exclude", [])]
+
+    return [
+        l
+        for l, t in full_task_graph.tasks.items()
+        if standard_filter(t, parameters)
+        and filter_out_shipping_phase(t, parameters)
+        and filter_out_devedition(t, parameters)
+        and filter_by_uncommon_try_tasks(t.label)
+        and filter_by_regex(t.label, include_regexes, mode="include")
+        and filter_by_regex(t.label, exclude_regexes, mode="exclude")
+        and filter_unsupported_artifact_builds(t, parameters)
+        and filter_out_shippable(t)
+    ]
+
+
+@_target_task("default")
+def target_tasks_default(full_task_graph, parameters, graph_config):
+    """Target the tasks which have indicated they should be run on this project
+    via the `run_on_projects` attributes."""
+    return [
+        l
+        for l, t in full_task_graph.tasks.items()
+        if standard_filter(t, parameters)
+        and filter_out_shipping_phase(t, parameters)
+        and filter_out_devedition(t, parameters)
+    ]
+
+
+@_target_task("autoland_tasks")
+def target_tasks_autoland(full_task_graph, parameters, graph_config):
+    """In addition to doing the filtering by project that the 'default'
+    filter does, also remove any tests running against shippable builds
+    for non-backstop pushes."""
+    filtered_for_project = target_tasks_default(
+        full_task_graph, parameters, graph_config
+    )
+
+    def filter(task):
+        if task.kind != "test":
+            return True
+
+        if parameters["backstop"]:
+            return True
+
+        build_type = task.attributes.get("build_type")
+
+        if not build_type or build_type != "opt" or filter_out_shippable(task):
+            return True
+
+        return False
+
+    return [l for l in filtered_for_project if filter(full_task_graph[l])]
+
+
+@_target_task("mozilla_central_tasks")
+def target_tasks_mozilla_central(full_task_graph, parameters, graph_config):
+    """In addition to doing the filtering by project that the 'default'
+    filter does, also remove any tests running against regular (aka not shippable,
+    asan, etc.) opt builds."""
+    filtered_for_project = target_tasks_default(
+        full_task_graph, parameters, graph_config
+    )
+
+    def filter(task):
+        if task.kind != "test":
+            return True
+
+        build_platform = task.attributes.get("build_platform")
+        build_type = task.attributes.get("build_type")
+        shippable = task.attributes.get("shippable", False)
+
+        if not build_platform or not build_type:
+            return True
+
+        family = platform_family(build_platform)
+        # We need to know whether this test is against a "regular" opt build
+        # (which is to say, not shippable, asan, tsan, or any other opt build
+        # with other properties). There's no positive test for this, so we have to
+        # do it somewhat hackily. Android doesn't have variants other than shippable
+        # so it is pretty straightforward to check for. Other platforms have many
+        # variants, but none of the regular opt builds we're looking for have a "-"
+        # in their platform name, so this works (for now).
+        is_regular_opt = (
+            family == "android" and not shippable
+        ) or "-" not in build_platform
+
+        if build_type != "opt" or not is_regular_opt:
+            return True
+
+        return False
+
+    return [l for l in filtered_for_project if filter(full_task_graph[l])]
+
+
+@_target_task("graphics_tasks")
+def target_tasks_graphics(full_task_graph, parameters, graph_config):
+    """In addition to doing the filtering by project that the 'default'
+    filter does, also remove artifact builds because we have csets on
+    the graphics branch that aren't on the candidate branches of artifact
+    builds"""
+    filtered_for_project = target_tasks_default(
+        full_task_graph, parameters, graph_config
+    )
+
+    def filter(task):
+        if task.attributes["kind"] == "artifact-build":
+            return False
+        return True
+
+    return [l for l in filtered_for_project if filter(full_task_graph[l])]
+
+
+@_target_task("mozilla_beta_tasks")
+def target_tasks_mozilla_beta(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a promotable beta or release build
+    of desktop, plus android CI. The candidates build process involves a pipeline
+    of builds and signing, but does not include beetmover or balrog jobs."""
+
+    return [
+        l
+        for l, t in full_task_graph.tasks.items()
+        if filter_release_tasks(t, parameters) and standard_filter(t, parameters)
+    ]
+
+
+@_target_task("mozilla_release_tasks")
+def target_tasks_mozilla_release(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a promotable beta or release build
+    of desktop, plus android CI. The candidates build process involves a pipeline
+    of builds and signing, but does not include beetmover or balrog jobs."""
+
+    return [
+        l
+        for l, t in full_task_graph.tasks.items()
+        if filter_release_tasks(t, parameters) and standard_filter(t, parameters)
+    ]
+
+
+@_target_task("mozilla_esr102_tasks")
+def target_tasks_mozilla_esr102(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a promotable beta or release build
+    of desktop, without android CI. The candidates build process involves a pipeline
+    of builds and signing, but does not include beetmover or balrog jobs."""
+
+    def filter(task):
+        if not filter_release_tasks(task, parameters):
+            return False
+
+        if not standard_filter(task, parameters):
+            return False
+
+        platform = task.attributes.get("build_platform")
+
+        # Android is not built on esr102.
+        if platform and "android" in platform:
+            return False
+
+        return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("mozilla_esr115_tasks")
+def target_tasks_mozilla_esr115(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a promotable beta or release build
+    of desktop, without android CI. The candidates build process involves a pipeline
+    of builds and signing, but does not include beetmover or balrog jobs."""
+
+    def filter(task):
+        if not filter_release_tasks(task, parameters):
+            return False
+
+        if not standard_filter(task, parameters):
+            return False
+
+        platform = task.attributes.get("build_platform")
+
+        # Android is not built on esr115.
+        if platform and "android" in platform:
+            return False
+
+        return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("promote_desktop")
+def target_tasks_promote_desktop(full_task_graph, parameters, graph_config):
+    """Select the superset of tasks required to promote a beta or release build
+    of a desktop product. This should include all non-android
+    mozilla_{beta,release} tasks, plus l10n, beetmover, balrog, etc."""
+
+    def filter(task):
+        # Bug 1758507 - geckoview ships in the promote phase
+        if not parameters["release_type"].startswith("esr") and is_geckoview(
+            task, parameters
+        ):
+            return True
+
+        if task.attributes.get("shipping_product") != parameters["release_product"]:
+            return False
+
+        # 'secondary' balrog/update verify/final verify tasks only run for RCs
+        if parameters.get("release_type") != "release-rc":
+            if "secondary" in task.kind:
+                return False
+
+        if not filter_out_missing_signoffs(task, parameters):
+            return False
+
+        if task.attributes.get("shipping_phase") == "promote":
+            return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+def is_geckoview(task, parameters):
+    return (
+        task.attributes.get("shipping_product") == "fennec"
+        and task.kind in ("beetmover-geckoview", "upload-symbols")
+        and parameters["release_product"] == "firefox"
+    )
+
+
+@_target_task("push_desktop")
+def target_tasks_push_desktop(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to push a build of desktop to cdns.
+    Previous build deps will be optimized out via action task."""
+    filtered_for_candidates = target_tasks_promote_desktop(
+        full_task_graph,
+        parameters,
+        graph_config,
+    )
+
+    def filter(task):
+        if not filter_out_missing_signoffs(task, parameters):
+            return False
+        # Include promotion tasks; these will be optimized out
+        if task.label in filtered_for_candidates:
+            return True
+
+        if (
+            task.attributes.get("shipping_product") == parameters["release_product"]
+            and task.attributes.get("shipping_phase") == "push"
+        ):
+            return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("ship_desktop")
+def target_tasks_ship_desktop(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to ship desktop.
+    Previous build deps will be optimized out via action task."""
+    is_rc = parameters.get("release_type") == "release-rc"
+    if is_rc:
+        # ship_firefox_rc runs after `promote` rather than `push`; include
+        # all promote tasks.
+        filtered_for_candidates = target_tasks_promote_desktop(
+            full_task_graph,
+            parameters,
+            graph_config,
+        )
+    else:
+        # ship_firefox runs after `push`; include all push tasks.
+        filtered_for_candidates = target_tasks_push_desktop(
+            full_task_graph,
+            parameters,
+            graph_config,
+        )
+
+    def filter(task):
+        if not filter_out_missing_signoffs(task, parameters):
+            return False
+        # Include promotion tasks; these will be optimized out
+        if task.label in filtered_for_candidates:
+            return True
+
+        if (
+            task.attributes.get("shipping_product") != parameters["release_product"]
+            or task.attributes.get("shipping_phase") != "ship"
+        ):
+            return False
+
+        if "secondary" in task.kind:
+            return is_rc
+        return not is_rc
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("pine_tasks")
+def target_tasks_pine(full_task_graph, parameters, graph_config):
+    """Bug 1339179 - no mobile automation needed on pine"""
+
+    def filter(task):
+        platform = task.attributes.get("build_platform")
+        # disable mobile jobs
+        if str(platform).startswith("android"):
+            return False
+        # disable asan
+        if platform == "linux64-asan":
+            return False
+        # disable non-pine and tasks with a shipping phase
+        if standard_filter(task, parameters) or filter_out_shipping_phase(
+            task, parameters
+        ):
+            return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("kaios_tasks")
+def target_tasks_kaios(full_task_graph, parameters, graph_config):
+    """The set of tasks to run for kaios integration"""
+
+    def filter(task):
+        # We disable everything in central, and adjust downstream.
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("ship_geckoview")
+def target_tasks_ship_geckoview(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to ship geckoview nightly. The
+    nightly build process involves a pipeline of builds and an upload to
+    maven.mozilla.org."""
+    index_path = (
+        f"{graph_config['trust-domain']}.v2.{parameters['project']}.revision."
+        f"{parameters['head_rev']}.taskgraph.decision-ship-geckoview"
+    )
+    if os.environ.get("MOZ_AUTOMATION") and retry(
+        index_exists,
+        args=(index_path,),
+        kwargs={
+            "reason": "to avoid triggering multiple nightlies off the same revision",
+        },
+    ):
+        return []
+
+    def filter(task):
+        # XXX Starting 69, we don't ship Fennec Nightly anymore. We just want geckoview to be
+        # uploaded
+        return task.attributes.get("shipping_product") == "fennec" and task.kind in (
+            "beetmover-geckoview",
+            "upload-symbols",
+        )
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("custom-car_perf_testing")
+def target_tasks_custom_car_perf_testing(full_task_graph, parameters, graph_config):
+    """Select tasks required for running daily performance tests for custom chromium-as-release."""
+
+    def filter(task):
+        platform = task.attributes.get("test_platform")
+        attributes = task.attributes
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+
+        try_name = attributes.get("raptor_try_name")
+
+        # Completely ignore all non-shippable platforms
+        if "shippable" not in platform:
+            return False
+
+        # ignore all windows 7 perf jobs scheduled automatically
+        if "windows7" in platform or "windows10-32" in platform:
+            return False
+
+        # Desktop selection only for CaR
+        if "android" not in platform:
+            if "browsertime" in try_name and "custom-car" in try_name:
+                return True
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("general_perf_testing")
+def target_tasks_general_perf_testing(full_task_graph, parameters, graph_config):
+    """
+    Select tasks required for running performance tests 3 times a week.
+    """
+
+    def filter(task):
+        platform = task.attributes.get("test_platform")
+        attributes = task.attributes
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+
+        try_name = attributes.get("raptor_try_name")
+
+        # Completely ignore all non-shippable platforms
+        if "shippable" not in platform:
+            return False
+
+        # ignore all windows 7 perf jobs scheduled automatically
+        if "windows7" in platform or "windows10-32" in platform:
+            return False
+
+        # Desktop selection
+        if "android" not in platform:
+            # Select some browsertime tasks as desktop smoke-tests
+            if "browsertime" in try_name:
+                if "chrome" in try_name:
+                    return True
+                if "chromium" in try_name:
+                    return True
+                # chromium-as-release has it's own cron
+                if "custom-car" in try_name:
+                    return False
+                if "-live" in try_name:
+                    return True
+                if "-fis" in try_name:
+                    return False
+                if "linux" in platform:
+                    if "speedometer" in try_name:
+                        return True
+                if "safari" and "benchmark" in try_name:
+                    # Speedometer 3 is broken on Safari, see bug 1802922
+                    if "speedometer3" in try_name:
+                        return False
+                    return True
+            else:
+                # Don't run tp6 raptor tests
+                if "tp6" in try_name:
+                    return False
+        # Android selection
+        elif accept_raptor_android_build(platform):
+            if "chrome-m" in try_name and (
+                ("ebay" in try_name and "live" not in try_name)
+                or (
+                    "live" in try_name
+                    and ("facebook" in try_name or "dailymail" in try_name)
+                )
+            ):
+                return False
+            # Ignore all fennec tests here, we run those weekly
+            if "fennec" in try_name:
+                return False
+            # Only run webrender tests
+            if "chrome-m" not in try_name and "-qr" not in platform:
+                return False
+            # Select live site tests
+            if "-live" in try_name:
+                return True
+            # Select fenix resource usage tests
+            if "fenix" in try_name:
+                # Bug 1816421 disable fission perf tests
+                if "-fis" in try_name:
+                    return False
+                if "-power" in try_name:
+                    return True
+            # Select geckoview resource usage tests
+            if "geckoview" in try_name:
+                # Bug 1816421 disable fission perf tests
+                if "-fis" in try_name:
+                    return False
+                # Run cpu+memory, and power tests
+                cpu_n_memory_task = "-cpu" in try_name and "-memory" in try_name
+                power_task = "-power" in try_name
+                # Ignore cpu+memory+power tests
+                if power_task and cpu_n_memory_task:
+                    return False
+                if cpu_n_memory_task:
+                    return False
+                if power_task:
+                    return "browsertime" in try_name
+            # Select browsertime-specific tests
+            if "browsertime" in try_name:
+                if "speedometer" in try_name:
+                    return True
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+def make_desktop_nightly_filter(platforms):
+    """Returns a filter that gets all nightly tasks on the given platform."""
+
+    def filter(task, parameters):
+        return all(
+            [
+                filter_on_platforms(task, platforms),
+                filter_for_project(task, parameters),
+                task.attributes.get("shippable", False),
+                # Tests and nightly only builds don't have `shipping_product` set
+                task.attributes.get("shipping_product")
+                in {None, "firefox", "thunderbird"},
+                task.kind not in {"l10n"},  # no on-change l10n
+            ]
+        )
+
+    return filter
+
+
+@_target_task("sp-perftests")
+def target_tasks_speedometer_tests(full_task_graph, parameters, graph_config):
+    def filter(task):
+        platform = task.attributes.get("test_platform")
+        attributes = task.attributes
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+        if "windows10-32" not in platform:
+            try_name = attributes.get("raptor_try_name")
+            if (
+                "browsertime" in try_name
+                and "speedometer" in try_name
+                and "chrome" in try_name
+            ):
+                return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("nightly_linux")
+def target_tasks_nightly_linux(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of linux. The
+    nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter({"linux64-shippable", "linux-shippable"})
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("nightly_macosx")
+def target_tasks_nightly_macosx(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of macosx. The
+    nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter({"macosx64-shippable"})
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("nightly_win32")
+def target_tasks_nightly_win32(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of win32 and win64.
+    The nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter({"win32-shippable"})
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("nightly_win64")
+def target_tasks_nightly_win64(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of win32 and win64.
+    The nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter({"win64-shippable"})
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("nightly_win64_aarch64")
+def target_tasks_nightly_win64_aarch64(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of win32 and win64.
+    The nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter({"win64-aarch64-shippable"})
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("nightly_asan")
+def target_tasks_nightly_asan(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of asan. The
+    nightly build process involves a pipeline of builds, signing,
+    and, eventually, uploading the tasks to balrog."""
+    filter = make_desktop_nightly_filter(
+        {"linux64-asan-reporter-shippable", "win64-asan-reporter-shippable"}
+    )
+    return [l for l, t in full_task_graph.tasks.items() if filter(t, parameters)]
+
+
+@_target_task("daily_releases")
+def target_tasks_daily_releases(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to identify if we should release.
+    If we determine that we should the task will communicate to ship-it to
+    schedule the release itself."""
+
+    def filter(task):
+        return task.kind in ["maybe-release"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("nightly_desktop")
+def target_tasks_nightly_desktop(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required for a nightly build of linux, mac,
+    windows."""
+    index_path = (
+        f"{graph_config['trust-domain']}.v2.{parameters['project']}.revision."
+        f"{parameters['head_rev']}.taskgraph.decision-nightly-desktop"
+    )
+    if os.environ.get("MOZ_AUTOMATION") and retry(
+        index_exists,
+        args=(index_path,),
+        kwargs={
+            "reason": "to avoid triggering multiple nightlies off the same revision",
+        },
+    ):
+        return []
+
+    # Tasks that aren't platform specific
+    release_filter = make_desktop_nightly_filter({None})
+    release_tasks = [
+        l for l, t in full_task_graph.tasks.items() if release_filter(t, parameters)
+    ]
+    # Avoid duplicate tasks.
+    return list(
+        set(target_tasks_nightly_win32(full_task_graph, parameters, graph_config))
+        | set(target_tasks_nightly_win64(full_task_graph, parameters, graph_config))
+        | set(
+            target_tasks_nightly_win64_aarch64(
+                full_task_graph, parameters, graph_config
+            )
+        )
+        | set(target_tasks_nightly_macosx(full_task_graph, parameters, graph_config))
+        | set(target_tasks_nightly_linux(full_task_graph, parameters, graph_config))
+        | set(target_tasks_nightly_asan(full_task_graph, parameters, graph_config))
+        | set(release_tasks)
+    )
+
+
+# Run Searchfox analysis once daily.
+@_target_task("searchfox_index")
+def target_tasks_searchfox(full_task_graph, parameters, graph_config):
+    """Select tasks required for indexing Firefox for Searchfox web site each day"""
+    return [
+        "searchfox-linux64-searchfox/debug",
+        "searchfox-macosx64-searchfox/debug",
+        "searchfox-win64-searchfox/debug",
+        "searchfox-android-armv7-searchfox/debug",
+        "source-test-file-metadata-bugzilla-components",
+        "source-test-file-metadata-test-info-all",
+        "source-test-wpt-metadata-summary",
+    ]
+
+
+# Run build linux64-plain-clang-trunk/opt on mozilla-central/beta with perf tests
+@_target_task("linux64_clang_trunk_perf")
+def target_tasks_build_linux64_clang_trunk_perf(
+    full_task_graph, parameters, graph_config
+):
+    """Select tasks required to run perf test on linux64 build with clang trunk"""
+
+    # Only keep tasks generated from platform `linux1804-64-clang-trunk-qr/opt`
+    def filter(task_label):
+        if "linux1804-64-clang-trunk-qr/opt" in task_label:
+            return True
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t.label)]
+
+
+# Run Updatebot's cron job 4 times daily.
+@_target_task("updatebot_cron")
+def target_tasks_updatebot_cron(full_task_graph, parameters, graph_config):
+    """Select tasks required to run Updatebot's cron job"""
+    return ["updatebot-cron"]
+
+
+@_target_task("customv8_update")
+def target_tasks_customv8_update(full_task_graph, parameters, graph_config):
+    """Select tasks required for building latest d8/v8 version."""
+    return ["toolchain-linux64-custom-v8"]
+
+
+@_target_task("chromium_update")
+def target_tasks_chromium_update(full_task_graph, parameters, graph_config):
+    """Select tasks required for building latest chromium versions."""
+    return [
+        "fetch-linux64-chromium",
+        "fetch-win32-chromium",
+        "fetch-win64-chromium",
+        "fetch-mac-chromium",
+        "toolchain-linux64-custom-car",
+        "toolchain-win64-custom-car",
+    ]
+
+
+@_target_task("file_update")
+def target_tasks_file_update(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to perform nightly in-tree file updates"""
+
+    def filter(task):
+        # For now any task in the repo-update kind is ok
+        return task.kind in ["repo-update"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("l10n_bump")
+def target_tasks_l10n_bump(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to perform l10n bumping."""
+
+    def filter(task):
+        # For now any task in the repo-update kind is ok
+        return task.kind in ["l10n-bump"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("merge_automation")
+def target_tasks_merge_automation(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to perform repository merges."""
+
+    def filter(task):
+        # For now any task in the repo-update kind is ok
+        return task.kind in ["merge-automation"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("scriptworker_canary")
+def target_tasks_scriptworker_canary(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to run scriptworker canaries."""
+
+    def filter(task):
+        # For now any task in the repo-update kind is ok
+        return task.kind in ["scriptworker-canary"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("cron_bouncer_check")
+def target_tasks_bouncer_check(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to perform bouncer version verification."""
+
+    def filter(task):
+        if not filter_for_project(task, parameters):
+            return False
+        # For now any task in the repo-update kind is ok
+        return task.kind in ["cron-bouncer-check"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("staging_release_builds")
+def target_tasks_staging_release(full_task_graph, parameters, graph_config):
+    """
+    Select all builds that are part of releases.
+    """
+
+    def filter(task):
+        if not task.attributes.get("shipping_product"):
+            return False
+        if parameters["release_type"].startswith(
+            "esr"
+        ) and "android" in task.attributes.get("build_platform", ""):
+            return False
+        if parameters["release_type"] != "beta" and "devedition" in task.attributes.get(
+            "build_platform", ""
+        ):
+            return False
+        if task.attributes.get("shipping_phase") == "build":
+            return True
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("release_simulation")
+def target_tasks_release_simulation(full_task_graph, parameters, graph_config):
+    """
+    Select builds that would run on push on a release branch.
+    """
+    project_by_release = {
+        "nightly": "mozilla-central",
+        "beta": "mozilla-beta",
+        "release": "mozilla-release",
+        "esr102": "mozilla-esr102",
+        "esr115": "mozilla-esr115",
+    }
+    target_project = project_by_release.get(parameters["release_type"])
+    if target_project is None:
+        raise Exception("Unknown or unspecified release type in simulation run.")
+
+    def filter_for_target_project(task):
+        """Filter tasks by project.  Optionally enable nightlies."""
+        run_on_projects = set(task.attributes.get("run_on_projects", []))
+        return match_run_on_projects(target_project, run_on_projects)
+
+    def filter_out_android_on_esr(task):
+        if parameters["release_type"].startswith(
+            "esr"
+        ) and "android" in task.attributes.get("build_platform", ""):
+            return False
+        return True
+
+    return [
+        l
+        for l, t in full_task_graph.tasks.items()
+        if filter_release_tasks(t, parameters)
+        and filter_out_cron(t, parameters)
+        and filter_for_target_project(t)
+        and filter_out_android_on_esr(t)
+    ]
+
+
+@_target_task("codereview")
+def target_tasks_codereview(full_task_graph, parameters, graph_config):
+    """Select all code review tasks needed to produce a report"""
+
+    def filter(task):
+        # Ending tasks
+        if task.kind in ["code-review"]:
+            return True
+
+        # Analyzer tasks
+        if task.attributes.get("code-review") is True:
+            return True
+
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("nothing")
+def target_tasks_nothing(full_task_graph, parameters, graph_config):
+    """Select nothing, for DONTBUILD pushes"""
+    return []
+
+
+@_target_task("daily_beta_perf")
+def target_tasks_daily_beta_perf(full_task_graph, parameters, graph_config):
+    """
+    Select performance tests on the beta branch to be run daily
+    """
+    index_path = (
+        f"{graph_config['trust-domain']}.v2.{parameters['project']}.revision."
+        f"{parameters['head_rev']}.taskgraph.decision-daily-beta-perf"
+    )
+    if os.environ.get("MOZ_AUTOMATION") and retry(
+        index_exists,
+        args=(index_path,),
+        kwargs={
+            "reason": "to avoid triggering multiple daily beta perftests off of the same revision",
+        },
+    ):
+        return []
+
+    def filter(task):
+        platform = task.attributes.get("test_platform")
+        attributes = task.attributes
+        try_name = attributes.get("raptor_try_name")
+
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+
+        if platform and accept_raptor_android_build(platform):
+            # Select browsertime & geckoview specific tests
+            if "browsertime" and "geckoview" in try_name:
+                if "g5" in platform:
+                    return False
+                if "power" in try_name:
+                    return False
+                if "cpu" in try_name:
+                    return False
+                if "profiling" in try_name:
+                    return False
+                if "-live" in try_name:
+                    return False
+                if "speedometer" in try_name:
+                    return True
+                if "webgl" in try_name:
+                    return True
+                if "tp6m" in try_name:
+                    return True
+
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("weekly_release_perf")
+def target_tasks_weekly_release_perf(full_task_graph, parameters, graph_config):
+    """
+    Select performance tests on the release branch to be run weekly
+    """
+
+    def filter(task):
+        platform = task.attributes.get("test_platform")
+        attributes = task.attributes
+        try_name = attributes.get("raptor_try_name")
+
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+
+        if platform and accept_raptor_android_build(platform):
+            # Select browsertime & geckoview specific tests
+            if "browsertime" and "geckoview" in try_name:
+                if "g5" in platform:
+                    return False
+                if "power" in try_name:
+                    return False
+                if "cpu" in try_name:
+                    return False
+                if "profiling" in try_name:
+                    return False
+                if "-live" in try_name:
+                    return False
+                if "speedometer" in try_name:
+                    return True
+                if "webgl" in try_name:
+                    return True
+                if "tp6m" in try_name:
+                    return True
+                if "youtube-playback" in try_name:
+                    return True
+
+        return False
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("raptor_tp6m")
+def target_tasks_raptor_tp6m(full_task_graph, parameters, graph_config):
+    """
+    Select tasks required for running raptor cold page-load tests on fenix and refbrow
+    """
+
+    def filter(task):
+        platform = task.attributes.get("build_platform")
+        attributes = task.attributes
+
+        if platform and "android" not in platform:
+            return False
+        if attributes.get("unittest_suite") != "raptor":
+            return False
+        try_name = attributes.get("raptor_try_name")
+        if "-cold" in try_name and "shippable" in platform:
+            # Get browsertime amazon smoke tests
+            if (
+                "browsertime" in try_name
+                and "amazon" in try_name
+                and "search" not in try_name
+                and "fenix" in try_name
+            ):
+                return True
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("backfill_all_browsertime")
+def target_tasks_backfill_all_browsertime(full_task_graph, parameters, graph_config):
+    """
+    Search for revisions that contains patches that were reviewed by perftest reviewers
+    and landed the day before the cron is running. Trigger backfill-all-browsertime action
+    task on each of them.
+    """
+    from gecko_taskgraph.actions.util import get_decision_task_id, get_pushes
+
+    def date_is_yesterday(date):
+        yesterday = datetime.today() - timedelta(days=1)
+        date = datetime.fromtimestamp(date)
+        return date.date() == yesterday.date()
+
+    def reviewed_by_perftest(push):
+        try:
+            commit_message = get_hg_commit_message(
+                os.path.join(GECKO, graph_config["product-dir"]), rev=push
+            )
+        except Exception as e:
+            print(e)
+            return False
+
+        for line in commit_message.split("\n\n"):
+            if line.lower().startswith("bug ") and "r=" in line:
+                if "perftest-reviewers" in line.split("r=")[-1]:
+                    print(line)
+                    return True
+        return False
+
+    pushes = get_pushes(
+        project=parameters["head_repository"],
+        end_id=int(parameters["pushlog_id"]),
+        depth=200,
+        full_response=True,
+    )
+    for push_id in sorted([int(p) for p in pushes.keys()], reverse=True):
+        push_rev = pushes[str(push_id)]["changesets"][-1]
+        push_info = find_hg_revision_push_info(
+            "https://hg.mozilla.org/integration/" + parameters["project"], push_rev
+        )
+        pushdate = int(push_info["pushdate"])
+        if date_is_yesterday(pushdate) and reviewed_by_perftest(push_rev):
+            from gecko_taskgraph.actions.util import trigger_action
+
+            print(
+                f"Revision {push_rev} was created yesterday and was reviewed by "
+                f"#perftest-reviewers."
+            )
+            try:
+                push_decision_task_id = get_decision_task_id(
+                    parameters["project"], push_id
+                )
+            except Exception:
+                print(f"Could not find decision task for push {push_id}")
+                continue
+            try:
+                trigger_action(
+                    action_name="backfill-all-browsertime",
+                    # This lets the action know on which push we want to add a new task
+                    decision_task_id=push_decision_task_id,
+                )
+            except Exception as e:
+                print(f"Failed to trigger action for {push_rev}: {e}")
+
+    return []
+
+
+@_target_task("condprof")
+def target_tasks_condprof(full_task_graph, parameters, graph_config):
+    """
+    Select tasks required for building conditioned profiles.
+    """
+    for name, task in full_task_graph.tasks.items():
+        if task.kind == "condprof":
+            if "a51" not in name:  # bug 1765348
+                yield name
+
+
+@_target_task("system_symbols")
+def target_tasks_system_symbols(full_task_graph, parameters, graph_config):
+    """
+    Select tasks for scraping and uploading system symbols.
+    """
+    for name, task in full_task_graph.tasks.items():
+        if task.kind in [
+            "system-symbols",
+            "system-symbols-upload",
+            "system-symbols-reprocess",
+        ]:
+            yield name
+
+
+@_target_task("perftest")
+def target_tasks_perftest(full_task_graph, parameters, graph_config):
+    """
+    Select perftest tasks we want to run daily
+    """
+    for name, task in full_task_graph.tasks.items():
+        if task.kind != "perftest":
+            continue
+        if task.attributes.get("cron", False):
+            yield name
+
+
+@_target_task("perftest-on-autoland")
+def target_tasks_perftest_autoland(full_task_graph, parameters, graph_config):
+    """
+    Select perftest tasks we want to run daily
+    """
+    for name, task in full_task_graph.tasks.items():
+        if task.kind != "perftest":
+            continue
+        if task.attributes.get("cron", False) and any(
+            test_name in name for test_name in ["view"]
+        ):
+            yield name
+
+
+@_target_task("l10n-cross-channel")
+def target_tasks_l10n_cross_channel(full_task_graph, parameters, graph_config):
+    """Select the set of tasks required to run l10n cross-channel."""
+
+    def filter(task):
+        return task.kind in ["l10n-cross-channel"]
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
+
+
+@_target_task("are-we-esmified-yet")
+def target_tasks_are_we_esmified_yet(full_task_graph, parameters, graph_config):
+    """
+    select the task to track the progress of the esmification project
+    """
+    return [
+        l for l, t in full_task_graph.tasks.items() if t.kind == "are-we-esmified-yet"
+    ]
+
+
+@_target_task("eslint-build")
+def target_tasks_eslint_build(full_task_graph, parameters, graph_config):
+    """Select the task to run additional ESLint rules which require a build."""
+
+    for name, task in full_task_graph.tasks.items():
+        if task.kind != "source-test":
+            continue
+        if "eslint-build" in name:
+            yield name
+
+
+@_target_task("holly_tasks")
+def target_tasks_holly(full_task_graph, parameters, graph_config):
+    """Bug 1814661: only run updatebot tasks on holly"""
+
+    def filter(task):
+        return task.kind == "updatebot"
+
+    return [l for l, t in full_task_graph.tasks.items() if filter(t)]
diff --git a/taskcluster/gecko_taskgraph/test/__init__.py b/taskcluster/gecko_taskgraph/test/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/__init__.py
diff --git a/taskcluster/gecko_taskgraph/test/automationrelevance.json b/taskcluster/gecko_taskgraph/test/automationrelevance.json
new file mode 100644
index 0000000000..3bdfa9ed9e
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/automationrelevance.json
@@ -0,0 +1,358 @@
+{
+  "changesets": [
+    {
+      "author": "James Long <longster@gmail.com>",
+      "backsoutnodes": [],
+      "bugs": [
+        {
+          "no": "1300866",
+          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1300866"
+        }
+      ],
+      "date": [1473196655.0, 14400],
+      "desc": "Bug 1300866 - expose devtools require to new debugger r=jlast,bgrins",
+      "extra": {
+        "branch": "default"
+      },
+      "files": ["devtools/client/debugger/index.html"],
+      "node": "ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+      "parents": ["37c9349b4e8167a61b08b7e119c21ea177b98942"],
+      "perfherderurl": "https://treeherder.mozilla.org/perf.html#/compare?originalProject=mozilla-central&originalRevision=a14f88a9af7a59e677478694bafd9375ac53683e&newProject=mozilla-central&newRevision=ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+      "pushdate": [1473261248, 0],
+      "pushhead": "a14f88a9af7a59e677478694bafd9375ac53683e",
+      "pushid": 30664,
+      "pushnodes": [
+        "ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+        "73a6a267a50a0e1c41e689b265ad3eebe43d7ac6",
+        "16a1a91f9269ab95dd83eb29dc5d0227665f7d94",
+        "99c542fa43a72ee863c813b5624048d1b443549b",
+        "a6b6a93eb41a05e310a11f0172f01ba9b21d3eac",
+        "541c9086c0f27fba60beecc9bc94543103895c86",
+        "041a925171e431bf51fb50193ab19d156088c89a",
+        "a14f88a9af7a59e677478694bafd9375ac53683e"
+      ],
+      "pushuser": "cbook@mozilla.com",
+      "rev": 312890,
+      "reviewers": [
+        {
+          "name": "jlast",
+          "revset": "reviewer(jlast)"
+        },
+        {
+          "name": "bgrins",
+          "revset": "reviewer(bgrins)"
+        }
+      ],
+      "treeherderrepo": "mozilla-central",
+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
+    {
+      "author": "Wes Kocher <wkocher@mozilla.com>",
+      "backsoutnodes": [],
+      "bugs": [],
+      "date": [1473208638.0, 25200],
+      "desc": "Merge m-c to fx-team, a=merge",
+      "extra": {
+        "branch": "default"
+      },
+      "files": ["taskcluster/scripts/builder/build-l10n.sh"],
+      "node": "73a6a267a50a0e1c41e689b265ad3eebe43d7ac6",
+      "parents": [
+        "ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+        "91c2b9d5c1354ca79e5b174591dbb03b32b15bbf"
+      ],
+      "perfherderurl": "https://treeherder.mozilla.org/perf.html#/compare?originalProject=mozilla-central&originalRevision=a14f88a9af7a59e677478694bafd9375ac53683e&newProject=mozilla-central&newRevision=ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+      "pushdate": [1473261248, 0],
+      "pushhead": "a14f88a9af7a59e677478694bafd9375ac53683e",
+      "pushid": 30664,
+      "pushnodes": [
+        "ae2144aa4356b65c2f8c0de8c9082dcb7e330e24",
+        "73a6a267a50a0e1c41e689b265ad3eebe43d7ac6",
+        "16a1a91f9269ab95dd83eb29dc5d0227665f7d94",
+        "99c542fa43a72ee863c813b5624048d1b443549b",
+        "a6b6a93eb41a05e310a11f0172f01ba9b21d3eac",
+        "541c9086c0f27fba60beecc9bc94543103895c86",
+        "041a925171e431bf51fb50193ab19d156088c89a",
+        "a14f88a9af7a59e677478694bafd9375ac53683e"
+      ],
+      "pushuser": "cbook@mozilla.com",
+      "rev": 312891,
+      "reviewers": [
+        {
+          "name": "merge",
+          "revset": "reviewer(merge)"
+        }
+      ],
+      "treeherderrepo": "mozilla-central",
+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
+    {
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+      "backsoutnodes": [],
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+      "extra": {
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+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
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+      "extra": {
+        "branch": "default"
+      },
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+        }
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+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
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+      "reviewers": [
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+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
+    {
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+      "backsoutnodes": [],
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+          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1299154"
+        }
+      ],
+      "date": [1472629906.0, -7200],
+      "desc": "Bug 1299154 - added Set/GetOverrideDPPX to restorefromHistory; r=mstange\n\nMozReview-Commit-ID: AsyAcG3Igbn\n",
+      "extra": {
+        "branch": "default",
+        "committer": "Matteo Ferretti <mferretti@mozilla.com> 1473236511 -7200"
+      },
+      "files": [
+        "docshell/base/nsDocShell.cpp",
+        "dom/tests/mochitest/general/test_contentViewer_overrideDPPX.html"
+      ],
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+      "treeherderrepourl": "https://treeherder.mozilla.org/#/jobs?repo=mozilla-central"
+    },
+    {
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+          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1295010"
+        }
+      ],
+      "date": [1473239449.0, -7200],
+      "desc": "Bug 1295010 - Removed testActor from highlighterHelper in inspector tests; r=me\n\nMozReview-Commit-ID: GMksl81iGcp",
+      "extra": {
+        "branch": "default"
+      },
+      "files": [
+        "devtools/client/inspector/test/browser_inspector_highlighter-eyedropper-events.js",
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+      ],
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+    },
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+  ],
+  "visible": true
+}
diff --git a/taskcluster/gecko_taskgraph/test/conftest.py b/taskcluster/gecko_taskgraph/test/conftest.py
new file mode 100644
index 0000000000..09231c5ab2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/conftest.py
@@ -0,0 +1,220 @@
+# Any copyright is dedicated to the public domain.
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+import os
+
+import pytest
+from mach.logging import LoggingManager
+from responses import RequestsMock
+from taskgraph import generator as generator_mod
+from taskgraph import target_tasks as target_tasks_mod
+from taskgraph.config import GraphConfig, load_graph_config
+from taskgraph.generator import Kind, TaskGraphGenerator
+from taskgraph.optimize import base as optimize_mod
+from taskgraph.optimize.base import OptimizationStrategy
+from taskgraph.parameters import Parameters
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.actions import render_actions_json
+from gecko_taskgraph.util.templates import merge
+
+
+@pytest.fixture
+def responses():
+    with RequestsMock() as rsps:
+        yield rsps
+
+
+@pytest.fixture(scope="session", autouse=True)
+def patch_prefherder(request):
+    from _pytest.monkeypatch import MonkeyPatch
+
+    m = MonkeyPatch()
+    m.setattr(
+        "gecko_taskgraph.util.bugbug._write_perfherder_data",
+        lambda lower_is_better: None,
+    )
+    yield
+    m.undo()
+
+
+@pytest.fixture(scope="session", autouse=True)
+def enable_logging():
+    """Ensure logs from gecko_taskgraph are displayed when a test fails."""
+    lm = LoggingManager()
+    lm.add_terminal_logging()
+
+
+@pytest.fixture(scope="session")
+def graph_config():
+    return load_graph_config(os.path.join(GECKO, "taskcluster", "ci"))
+
+
+@pytest.fixture(scope="session")
+def actions_json(graph_config):
+    decision_task_id = "abcdef"
+    return render_actions_json(Parameters(strict=False), graph_config, decision_task_id)
+
+
+def fake_loader(kind, path, config, parameters, loaded_tasks):
+    for i in range(3):
+        dependencies = {}
+        if i >= 1:
+            dependencies["prev"] = f"{kind}-t-{i - 1}"
+
+        task = {
+            "kind": kind,
+            "label": f"{kind}-t-{i}",
+            "description": f"{kind} task {i}",
+            "attributes": {"_tasknum": str(i)},
+            "task": {
+                "i": i,
+                "metadata": {"name": f"t-{i}"},
+                "deadline": "soon",
+            },
+            "dependencies": dependencies,
+        }
+        if "job-defaults" in config:
+            task = merge(config["job-defaults"], task)
+        yield task
+
+
+class FakeTransform:
+    transforms = []
+    params = {}
+
+    def __init__(self):
+        pass
+
+    @classmethod
+    def get(self, field, default):
+        try:
+            return getattr(self, field)
+        except AttributeError:
+            return default
+
+
+class FakeKind(Kind):
+    def _get_loader(self):
+        return fake_loader
+
+    def load_tasks(self, parameters, loaded_tasks, write_artifacts):
+        FakeKind.loaded_kinds.append(self.name)
+        return super().load_tasks(parameters, loaded_tasks, write_artifacts)
+
+    @staticmethod
+    def create(name, extra_config, graph_config):
+        if name == "fullfake":
+            config = FakeTransform()
+        else:
+            config = {"transforms": []}
+        if extra_config:
+            config.update(extra_config)
+        return FakeKind(name, "/fake", config, graph_config)
+
+
+class WithFakeKind(TaskGraphGenerator):
+    def _load_kinds(self, graph_config, target_kind=None):
+        for kind_name, cfg in self.parameters["_kinds"]:
+            yield FakeKind.create(kind_name, cfg, graph_config)
+
+
+def fake_load_graph_config(root_dir):
+    graph_config = GraphConfig(
+        {"trust-domain": "test-domain", "taskgraph": {}}, root_dir
+    )
+    graph_config.__dict__["register"] = lambda: None
+    return graph_config
+
+
+class FakeParameters(dict):
+    strict = True
+
+    def file_url(self, path, pretty=False):
+        return ""
+
+
+class FakeOptimization(OptimizationStrategy):
+    description = "Fake strategy for testing"
+
+    def __init__(self, mode, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.mode = mode
+
+    def should_remove_task(self, task, params, arg):
+        if self.mode == "always":
+            return True
+        if self.mode == "even":
+            return task.task["i"] % 2 == 0
+        if self.mode == "odd":
+            return task.task["i"] % 2 != 0
+        return False
+
+
+@pytest.fixture
+def maketgg(monkeypatch):
+    def inner(target_tasks=None, kinds=[("_fake", [])], params=None):
+        params = params or {}
+        FakeKind.loaded_kinds = loaded_kinds = []
+        target_tasks = target_tasks or []
+
+        def target_tasks_method(full_task_graph, parameters, graph_config):
+            return target_tasks
+
+        fake_registry = {
+            mode: FakeOptimization(mode) for mode in ("always", "never", "even", "odd")
+        }
+
+        target_tasks_mod._target_task_methods["test_method"] = target_tasks_method
+        monkeypatch.setattr(optimize_mod, "registry", fake_registry)
+
+        parameters = FakeParameters(
+            {
+                "_kinds": kinds,
+                "backstop": False,
+                "enable_always_target": False,
+                "target_tasks_method": "test_method",
+                "test_manifest_loader": "default",
+                "try_mode": None,
+                "try_task_config": {},
+                "tasks_for": "hg-push",
+                "project": "mozilla-central",
+            }
+        )
+        parameters.update(params)
+
+        monkeypatch.setattr(generator_mod, "load_graph_config", fake_load_graph_config)
+
+        tgg = WithFakeKind("/root", parameters)
+        tgg.loaded_kinds = loaded_kinds
+        return tgg
+
+    return inner
+
+
+@pytest.fixture
+def run_transform():
+
+    graph_config = fake_load_graph_config("/root")
+    kind = FakeKind.create("fake", {}, graph_config)
+
+    def inner(xform, tasks):
+        if isinstance(tasks, dict):
+            tasks = [tasks]
+        return xform(kind.config, tasks)
+
+    return inner
+
+
+@pytest.fixture
+def run_full_config_transform():
+
+    graph_config = fake_load_graph_config("/root")
+    kind = FakeKind.create("fullfake", {}, graph_config)
+
+    def inner(xform, tasks):
+        if isinstance(tasks, dict):
+            tasks = [tasks]
+        return xform(kind.config, tasks)
+
+    return inner
diff --git a/taskcluster/gecko_taskgraph/test/docs/kinds.rst b/taskcluster/gecko_taskgraph/test/docs/kinds.rst
new file mode 100644
index 0000000000..fdc16db1e3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/docs/kinds.rst
@@ -0,0 +1,12 @@
+Task Kinds
+==========
+
+Fake task kind documentation.
+
+newkind
+----------
+Kind found in separate doc dir,
+
+anotherkind
+-----------
+Here's another.
diff --git a/taskcluster/gecko_taskgraph/test/docs/parameters.rst b/taskcluster/gecko_taskgraph/test/docs/parameters.rst
new file mode 100644
index 0000000000..f943f48e69
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/docs/parameters.rst
@@ -0,0 +1,14 @@
+==========
+Parameters
+==========
+
+Fake parameters documentation.
+
+Heading
+-------
+
+``newparameter``
+  A new parameter that could be defined in a project.
+
+``anotherparameter``
+  And here is another one.
diff --git a/taskcluster/gecko_taskgraph/test/python.ini b/taskcluster/gecko_taskgraph/test/python.ini
new file mode 100644
index 0000000000..2dca8fc144
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/python.ini
@@ -0,0 +1,23 @@
+[DEFAULT]
+subsuite = taskgraph
+
+[test_actions_util.py]
+[test_decision.py]
+[test_files_changed.py]
+[test_main.py]
+[test_morph.py]
+[test_optimize_strategies.py]
+[test_target_tasks.py]
+[test_taskcluster_yml.py]
+[test_transforms_job.py]
+[test_transforms_test.py]
+[test_try_option_syntax.py]
+[test_util_attributes.py]
+[test_util_backstop.py]
+[test_util_bugbug.py]
+[test_util_chunking.py]
+[test_util_docker.py]
+[test_util_partials.py]
+[test_util_runnable_jobs.py]
+[test_util_templates.py]
+[test_util_verify.py]
diff --git a/taskcluster/gecko_taskgraph/test/test_actions_util.py b/taskcluster/gecko_taskgraph/test/test_actions_util.py
new file mode 100644
index 0000000000..7c38caea57
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_actions_util.py
@@ -0,0 +1,179 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import unittest
+from pprint import pprint
+from unittest.mock import patch
+
+import pytest
+from mozunit import MockedOpen, main
+from taskgraph import create
+from taskgraph.util import taskcluster
+
+from gecko_taskgraph import actions
+from gecko_taskgraph.actions.util import combine_task_graph_files, relativize_datestamps
+from gecko_taskgraph.decision import read_artifact
+
+TASK_DEF = {
+    "created": "2017-10-10T18:33:03.460Z",
+    # note that this is not an even number of seconds off!
+    "deadline": "2017-10-11T18:33:03.461Z",
+    "dependencies": [],
+    "expires": "2018-10-10T18:33:04.461Z",
+    "payload": {
+        "artifacts": {
+            "public": {
+                "expires": "2018-10-10T18:33:03.463Z",
+                "path": "/builds/worker/artifacts",
+                "type": "directory",
+            },
+        },
+        "maxRunTime": 1800,
+    },
+}
+
+
+@pytest.fixture(scope="module", autouse=True)
+def enable_test_mode():
+    create.testing = True
+    taskcluster.testing = True
+
+
+class TestRelativize(unittest.TestCase):
+    def test_relativize(self):
+        rel = relativize_datestamps(TASK_DEF)
+        import pprint
+
+        pprint.pprint(rel)
+        assert rel["created"] == {"relative-datestamp": "0 seconds"}
+        assert rel["deadline"] == {"relative-datestamp": "86400 seconds"}
+        assert rel["expires"] == {"relative-datestamp": "31536001 seconds"}
+        assert rel["payload"]["artifacts"]["public"]["expires"] == {
+            "relative-datestamp": "31536000 seconds"
+        }
+
+
+class TestCombineTaskGraphFiles(unittest.TestCase):
+    def test_no_suffixes(self):
+        with MockedOpen({}):
+            combine_task_graph_files([])
+            self.assertRaises(Exception, open("artifacts/to-run.json"))
+
+    @patch("gecko_taskgraph.actions.util.rename_artifact")
+    def test_one_suffix(self, rename_artifact):
+        combine_task_graph_files(["0"])
+        rename_artifact.assert_any_call("task-graph-0.json", "task-graph.json")
+        rename_artifact.assert_any_call(
+            "label-to-taskid-0.json", "label-to-taskid.json"
+        )
+        rename_artifact.assert_any_call("to-run-0.json", "to-run.json")
+
+    def test_several_suffixes(self):
+        files = {
+            "artifacts/task-graph-0.json": json.dumps({"taska": {}}),
+            "artifacts/label-to-taskid-0.json": json.dumps({"taska": "TASKA"}),
+            "artifacts/to-run-0.json": json.dumps(["taska"]),
+            "artifacts/task-graph-1.json": json.dumps({"taskb": {}}),
+            "artifacts/label-to-taskid-1.json": json.dumps({"taskb": "TASKB"}),
+            "artifacts/to-run-1.json": json.dumps(["taskb"]),
+        }
+        with MockedOpen(files):
+            combine_task_graph_files(["0", "1"])
+            self.assertEqual(
+                read_artifact("task-graph.json"),
+                {
+                    "taska": {},
+                    "taskb": {},
+                },
+            )
+            self.assertEqual(
+                read_artifact("label-to-taskid.json"),
+                {
+                    "taska": "TASKA",
+                    "taskb": "TASKB",
+                },
+            )
+            self.assertEqual(
+                sorted(read_artifact("to-run.json")),
+                [
+                    "taska",
+                    "taskb",
+                ],
+            )
+
+
+def is_subset(subset, superset):
+    if isinstance(subset, dict):
+        return all(
+            key in superset and is_subset(val, superset[key])
+            for key, val in subset.items()
+        )
+
+    if isinstance(subset, list) or isinstance(subset, set):
+        return all(
+            any(is_subset(subitem, superitem) for superitem in superset)
+            for subitem in subset
+        )
+
+    if isinstance(subset, str):
+        return subset in superset
+
+    # assume that subset is a plain value if none of the above match
+    return subset == superset
+
+
+@pytest.mark.parametrize(
+    "task_def,expected",
+    [
+        pytest.param(
+            {"tags": {"kind": "decision-task"}},
+            {
+                "hookPayload": {
+                    "decision": {
+                        "action": {"cb_name": "retrigger-decision"},
+                    },
+                },
+            },
+            id="retrigger_decision",
+        ),
+        pytest.param(
+            {"tags": {"action": "backfill-task"}},
+            {
+                "hookPayload": {
+                    "decision": {
+                        "action": {"cb_name": "retrigger-decision"},
+                    },
+                },
+            },
+            id="retrigger_backfill",
+        ),
+    ],
+)
+def test_extract_applicable_action(
+    responses, monkeypatch, actions_json, task_def, expected
+):
+    base_url = "https://taskcluster"
+    decision_task_id = "dddd"
+    task_id = "tttt"
+
+    monkeypatch.setenv("TASK_ID", task_id)
+    monkeypatch.setenv("TASKCLUSTER_ROOT_URL", base_url)
+    monkeypatch.setenv("TASKCLUSTER_PROXY_URL", base_url)
+    responses.add(
+        responses.GET,
+        f"{base_url}/api/queue/v1/task/{task_id}",
+        status=200,
+        json=task_def,
+    )
+    action = actions.util._extract_applicable_action(
+        actions_json, "retrigger", decision_task_id, task_id
+    )
+    pprint(action, indent=2)
+    assert is_subset(expected, action)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_decision.py b/taskcluster/gecko_taskgraph/test/test_decision.py
new file mode 100644
index 0000000000..81be7e0c44
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_decision.py
@@ -0,0 +1,176 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+import shutil
+import tempfile
+import unittest
+from unittest.mock import patch
+
+import pytest
+from mozunit import MockedOpen, main
+from taskgraph.util.yaml import load_yaml
+
+from gecko_taskgraph import decision
+from gecko_taskgraph.parameters import register_parameters
+
+FAKE_GRAPH_CONFIG = {"product-dir": "browser", "taskgraph": {}}
+
+
+@pytest.fixture(scope="module", autouse=True)
+def register():
+    register_parameters()
+
+
+class TestDecision(unittest.TestCase):
+    def test_write_artifact_json(self):
+        data = [{"some": "data"}]
+        tmpdir = tempfile.mkdtemp()
+        try:
+            decision.ARTIFACTS_DIR = os.path.join(tmpdir, "artifacts")
+            decision.write_artifact("artifact.json", data)
+            with open(os.path.join(decision.ARTIFACTS_DIR, "artifact.json")) as f:
+                self.assertEqual(json.load(f), data)
+        finally:
+            if os.path.exists(tmpdir):
+                shutil.rmtree(tmpdir)
+            decision.ARTIFACTS_DIR = "artifacts"
+
+    def test_write_artifact_yml(self):
+        data = [{"some": "data"}]
+        tmpdir = tempfile.mkdtemp()
+        try:
+            decision.ARTIFACTS_DIR = os.path.join(tmpdir, "artifacts")
+            decision.write_artifact("artifact.yml", data)
+            self.assertEqual(load_yaml(decision.ARTIFACTS_DIR, "artifact.yml"), data)
+        finally:
+            if os.path.exists(tmpdir):
+                shutil.rmtree(tmpdir)
+            decision.ARTIFACTS_DIR = "artifacts"
+
+
+class TestGetDecisionParameters(unittest.TestCase):
+
+    ttc_file = os.path.join(os.getcwd(), "try_task_config.json")
+
+    def setUp(self):
+        self.options = {
+            "base_repository": "https://hg.mozilla.org/mozilla-unified",
+            "head_repository": "https://hg.mozilla.org/mozilla-central",
+            "head_rev": "abcd",
+            "head_ref": "ef01",
+            "head_tag": "",
+            "message": "",
+            "project": "mozilla-central",
+            "pushlog_id": "143",
+            "pushdate": 1503691511,
+            "owner": "nobody@mozilla.com",
+            "repository_type": "hg",
+            "tasks_for": "hg-push",
+            "level": "3",
+        }
+
+    @patch("gecko_taskgraph.decision.get_hg_revision_branch")
+    @patch("gecko_taskgraph.decision._determine_more_accurate_base_rev")
+    def test_simple_options(
+        self, mock_determine_more_accurate_base_rev, mock_get_hg_revision_branch
+    ):
+        mock_get_hg_revision_branch.return_value = "default"
+        mock_determine_more_accurate_base_rev.return_value = "baserev"
+        with MockedOpen({self.ttc_file: None}):
+            params = decision.get_decision_parameters(FAKE_GRAPH_CONFIG, self.options)
+        self.assertEqual(params["pushlog_id"], "143")
+        self.assertEqual(params["build_date"], 1503691511)
+        self.assertEqual(params["hg_branch"], "default")
+        self.assertEqual(params["moz_build_date"], "20170825200511")
+        self.assertEqual(params["try_mode"], None)
+        self.assertEqual(params["try_options"], None)
+        self.assertEqual(params["try_task_config"], {})
+
+    @patch("gecko_taskgraph.decision.get_hg_revision_branch")
+    @patch("gecko_taskgraph.decision._determine_more_accurate_base_rev")
+    def test_no_email_owner(
+        self, mock_determine_more_accurate_base_rev, mock_get_hg_revision_branch
+    ):
+        mock_get_hg_revision_branch.return_value = "default"
+        mock_determine_more_accurate_base_rev.return_value = "baserev"
+        self.options["owner"] = "ffxbld"
+        with MockedOpen({self.ttc_file: None}):
+            params = decision.get_decision_parameters(FAKE_GRAPH_CONFIG, self.options)
+        self.assertEqual(params["owner"], "ffxbld@noreply.mozilla.org")
+
+    @patch("gecko_taskgraph.decision.get_hg_revision_branch")
+    @patch("gecko_taskgraph.decision.get_hg_commit_message")
+    @patch("gecko_taskgraph.decision._determine_more_accurate_base_rev")
+    def test_try_options(
+        self,
+        mock_determine_more_accurate_base_rev,
+        mock_get_hg_commit_message,
+        mock_get_hg_revision_branch,
+    ):
+        mock_get_hg_commit_message.return_value = "try: -b do -t all --artifact"
+        mock_get_hg_revision_branch.return_value = "default"
+        mock_determine_more_accurate_base_rev.return_value = "baserev"
+        self.options["project"] = "try"
+        with MockedOpen({self.ttc_file: None}):
+            params = decision.get_decision_parameters(FAKE_GRAPH_CONFIG, self.options)
+        self.assertEqual(params["try_mode"], "try_option_syntax")
+        self.assertEqual(params["try_options"]["build_types"], "do")
+        self.assertEqual(params["try_options"]["unittests"], "all")
+        self.assertEqual(
+            params["try_task_config"],
+            {
+                "gecko-profile": False,
+                "use-artifact-builds": True,
+                "env": {},
+            },
+        )
+
+    @patch("gecko_taskgraph.decision.get_hg_revision_branch")
+    @patch("gecko_taskgraph.decision.get_hg_commit_message")
+    @patch("gecko_taskgraph.decision._determine_more_accurate_base_rev")
+    def test_try_task_config(
+        self,
+        mock_get_hg_commit_message,
+        mock_get_hg_revision_branch,
+        mock_determine_more_accurate_base_rev,
+    ):
+        mock_get_hg_commit_message.return_value = "Fuzzy query=foo"
+        mock_get_hg_revision_branch.return_value = "default"
+        mock_determine_more_accurate_base_rev.return_value = "baserev"
+        ttc = {"tasks": ["a", "b"]}
+        self.options["project"] = "try"
+        with MockedOpen({self.ttc_file: json.dumps(ttc)}):
+            params = decision.get_decision_parameters(FAKE_GRAPH_CONFIG, self.options)
+            self.assertEqual(params["try_mode"], "try_task_config")
+            self.assertEqual(params["try_options"], None)
+            self.assertEqual(params["try_task_config"], ttc)
+
+    def test_try_syntax_from_message_empty(self):
+        self.assertEqual(decision.try_syntax_from_message(""), "")
+
+    def test_try_syntax_from_message_no_try_syntax(self):
+        self.assertEqual(decision.try_syntax_from_message("abc | def"), "")
+
+    def test_try_syntax_from_message_initial_try_syntax(self):
+        self.assertEqual(
+            decision.try_syntax_from_message("try: -f -o -o"), "try: -f -o -o"
+        )
+
+    def test_try_syntax_from_message_initial_try_syntax_multiline(self):
+        self.assertEqual(
+            decision.try_syntax_from_message("try: -f -o -o\nabc\ndef"), "try: -f -o -o"
+        )
+
+    def test_try_syntax_from_message_embedded_try_syntax_multiline(self):
+        self.assertEqual(
+            decision.try_syntax_from_message("some stuff\ntry: -f -o -o\nabc\ndef"),
+            "try: -f -o -o",
+        )
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_files_changed.py b/taskcluster/gecko_taskgraph/test/test_files_changed.py
new file mode 100644
index 0000000000..5b9a016649
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_files_changed.py
@@ -0,0 +1,90 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+import unittest
+
+from mozunit import main
+
+from gecko_taskgraph import files_changed
+from gecko_taskgraph.util import hg
+
+PARAMS = {
+    "head_repository": "https://hg.mozilla.org/mozilla-central",
+    "head_rev": "a14f88a9af7a",
+}
+
+FILES_CHANGED = [
+    "devtools/client/debugger/index.html",
+    "devtools/client/inspector/test/browser_inspector_highlighter-eyedropper-events.js",
+    "devtools/client/inspector/test/head.js",
+    "devtools/client/themes/rules.css",
+    "devtools/client/webconsole/test/browser_webconsole_output_06.js",
+    "devtools/server/actors/highlighters/eye-dropper.js",
+    "devtools/server/actors/object.js",
+    "docshell/base/nsDocShell.cpp",
+    "dom/tests/mochitest/general/test_contentViewer_overrideDPPX.html",
+    "taskcluster/scripts/builder/build-l10n.sh",
+]
+
+
+class FakeResponse:
+    def json(self):
+        with open(
+            os.path.join(os.path.dirname(__file__), "automationrelevance.json")
+        ) as f:
+            return json.load(f)
+
+
+class TestGetChangedFiles(unittest.TestCase):
+    def setUp(self):
+        files_changed.get_changed_files.clear()
+        self.old_get = hg.requests.get
+
+        def fake_get(url, **kwargs):
+            return FakeResponse()
+
+        hg.requests.get = fake_get
+
+    def tearDown(self):
+        hg.requests.get = self.old_get
+        files_changed.get_changed_files.clear()
+
+    def test_get_changed_files(self):
+        """Get_changed_files correctly gets the list of changed files in a push.
+        This tests against the production hg.mozilla.org so that it will detect
+        any changes in the format of the returned data."""
+        self.assertEqual(
+            sorted(
+                files_changed.get_changed_files(
+                    PARAMS["head_repository"], PARAMS["head_rev"]
+                )
+            ),
+            FILES_CHANGED,
+        )
+
+
+class TestCheck(unittest.TestCase):
+    def setUp(self):
+        files_changed.get_changed_files[
+            PARAMS["head_repository"], PARAMS["head_rev"]
+        ] = FILES_CHANGED
+
+    def tearDown(self):
+        files_changed.get_changed_files.clear()
+
+    def test_check_no_params(self):
+        self.assertTrue(files_changed.check({}, ["ignored"]))
+
+    def test_check_no_match(self):
+        self.assertFalse(files_changed.check(PARAMS, ["nosuch/**"]))
+
+    def test_check_match(self):
+        self.assertTrue(files_changed.check(PARAMS, ["devtools/**"]))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_main.py b/taskcluster/gecko_taskgraph/test/test_main.py
new file mode 100644
index 0000000000..bb1aa1caeb
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_main.py
@@ -0,0 +1,67 @@
+# Any copyright is dedicated to the public domain.
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+import pytest
+from mozunit import main as mozunit_main
+
+import gecko_taskgraph
+from gecko_taskgraph.main import main as taskgraph_main
+
+
+@pytest.fixture
+def run_main(maketgg, monkeypatch):
+    def inner(args, **kwargs):
+        kwargs.setdefault("target_tasks", ["_fake-t-0", "_fake-t-1"])
+        tgg = maketgg(**kwargs)
+
+        def fake_get_taskgraph_generator(*args):
+            return tgg
+
+        monkeypatch.setattr(
+            gecko_taskgraph.main,
+            "get_taskgraph_generator",
+            fake_get_taskgraph_generator,
+        )
+        taskgraph_main(args)
+        return tgg
+
+    return inner
+
+
+@pytest.mark.parametrize(
+    "attr,expected",
+    (
+        ("tasks", ["_fake-t-0", "_fake-t-1", "_fake-t-2"]),
+        ("full", ["_fake-t-0", "_fake-t-1", "_fake-t-2"]),
+        ("target", ["_fake-t-0", "_fake-t-1"]),
+        ("target-graph", ["_fake-t-0", "_fake-t-1"]),
+        ("optimized", ["_fake-t-0", "_fake-t-1"]),
+        ("morphed", ["_fake-t-0", "_fake-t-1"]),
+    ),
+)
+def test_show_taskgraph(run_main, capsys, attr, expected):
+    run_main([attr])
+    out, err = capsys.readouterr()
+    assert out.strip() == "\n".join(expected)
+    assert "Dumping result" in err
+
+
+def test_tasks_regex(run_main, capsys):
+    run_main(["full", "--tasks=_.*-t-1"])
+    out, _ = capsys.readouterr()
+    assert out.strip() == "_fake-t-1"
+
+
+def test_output_file(run_main, tmpdir):
+    output_file = tmpdir.join("out.txt")
+    assert not output_file.check()
+
+    run_main(["full", f"--output-file={output_file.strpath}"])
+    assert output_file.check()
+    assert output_file.read_text("utf-8").strip() == "\n".join(
+        ["_fake-t-0", "_fake-t-1", "_fake-t-2"]
+    )
+
+
+if __name__ == "__main__":
+    mozunit_main()
diff --git a/taskcluster/gecko_taskgraph/test/test_morph.py b/taskcluster/gecko_taskgraph/test/test_morph.py
new file mode 100644
index 0000000000..c29fb58207
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_morph.py
@@ -0,0 +1,108 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import pytest
+from mozunit import main
+from taskgraph.graph import Graph
+from taskgraph.parameters import Parameters
+from taskgraph.task import Task
+from taskgraph.taskgraph import TaskGraph
+
+from gecko_taskgraph import morph
+
+
+@pytest.fixture
+def make_taskgraph():
+    def inner(tasks):
+        label_to_taskid = {k: k + "-tid" for k in tasks}
+        for label, task_id in label_to_taskid.items():
+            tasks[label].task_id = task_id
+        graph = Graph(nodes=set(tasks), edges=set())
+        taskgraph = TaskGraph(tasks, graph)
+        return taskgraph, label_to_taskid
+
+    return inner
+
+
+def test_make_index_tasks(make_taskgraph, graph_config):
+    task_def = {
+        "routes": [
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.es-MX",
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.fy-NL",
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.sk",
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.sl",
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.uk",
+            "index.gecko.v2.mozilla-central.latest.firefox-l10n.linux64-opt.zh-CN",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.es-MX",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.fy-NL",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.sk",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.sl",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.uk",
+            "index.gecko.v2.mozilla-central.pushdate."
+            "2017.04.04.20170404100210.firefox-l10n.linux64-opt.zh-CN",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.es-MX",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.fy-NL",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.sk",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.sl",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.uk",
+            "index.gecko.v2.mozilla-central.revision."
+            "b5d8b27a753725c1de41ffae2e338798f3b5cacd.firefox-l10n.linux64-opt.zh-CN",
+        ],
+        "deadline": "soon",
+        "metadata": {
+            "description": "desc",
+            "owner": "owner@foo.com",
+            "source": "https://source",
+        },
+        "extra": {
+            "index": {"rank": 1540722354},
+        },
+    }
+    task = Task(kind="test", label="a", attributes={}, task=task_def)
+    docker_task = Task(
+        kind="docker-image", label="docker-image-index-task", attributes={}, task={}
+    )
+    taskgraph, label_to_taskid = make_taskgraph(
+        {
+            task.label: task,
+            docker_task.label: docker_task,
+        }
+    )
+
+    index_paths = [
+        r.split(".", 1)[1] for r in task_def["routes"] if r.startswith("index.")
+    ]
+    index_task = morph.make_index_task(
+        task,
+        taskgraph,
+        label_to_taskid,
+        Parameters(strict=False),
+        graph_config,
+        index_paths=index_paths,
+        index_rank=1540722354,
+        purpose="index-task",
+        dependencies={},
+    )
+
+    assert index_task.task["payload"]["command"][0] == "insert-indexes.js"
+    assert index_task.task["payload"]["env"]["TARGET_TASKID"] == "a-tid"
+    assert index_task.task["payload"]["env"]["INDEX_RANK"] == 1540722354
+
+    # check the scope summary
+    assert index_task.task["scopes"] == ["index:insert-task:gecko.v2.mozilla-central.*"]
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_optimize_strategies.py b/taskcluster/gecko_taskgraph/test/test_optimize_strategies.py
new file mode 100644
index 0000000000..0f37332300
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_optimize_strategies.py
@@ -0,0 +1,551 @@
+# Any copyright is dedicated to the public domain.
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+
+import time
+from datetime import datetime
+from time import mktime
+
+import pytest
+from mozunit import main
+from taskgraph.optimize.base import registry
+from taskgraph.task import Task
+
+from gecko_taskgraph.optimize import project
+from gecko_taskgraph.optimize.backstop import SkipUnlessBackstop, SkipUnlessPushInterval
+from gecko_taskgraph.optimize.bugbug import (
+    FALLBACK,
+    BugBugPushSchedules,
+    DisperseGroups,
+    SkipUnlessDebug,
+)
+from gecko_taskgraph.optimize.strategies import IndexSearch, SkipUnlessSchedules
+from gecko_taskgraph.util.backstop import BACKSTOP_PUSH_INTERVAL
+from gecko_taskgraph.util.bugbug import (
+    BUGBUG_BASE_URL,
+    BugbugTimeoutException,
+    push_schedules,
+)
+
+
+@pytest.fixture(autouse=True)
+def clear_push_schedules_memoize():
+    push_schedules.clear()
+
+
+@pytest.fixture
+def params():
+    return {
+        "branch": "autoland",
+        "head_repository": "https://hg.mozilla.org/integration/autoland",
+        "head_rev": "abcdef",
+        "project": "autoland",
+        "pushlog_id": 1,
+        "pushdate": mktime(datetime.now().timetuple()),
+    }
+
+
+def generate_tasks(*tasks):
+    for i, task in enumerate(tasks):
+        task.setdefault("label", f"task-{i}-label")
+        task.setdefault("kind", "test")
+        task.setdefault("task", {})
+        task.setdefault("attributes", {})
+        task["attributes"].setdefault("e10s", True)
+
+        for attr in (
+            "optimization",
+            "dependencies",
+            "soft_dependencies",
+        ):
+            task.setdefault(attr, None)
+
+        task["task"].setdefault("label", task["label"])
+        yield Task.from_json(task)
+
+
+# task sets
+
+default_tasks = list(
+    generate_tasks(
+        {"attributes": {"test_manifests": ["foo/test.ini", "bar/test.ini"]}},
+        {"attributes": {"test_manifests": ["bar/test.ini"], "build_type": "debug"}},
+        {"attributes": {"build_type": "debug"}},
+        {"attributes": {"test_manifests": [], "build_type": "opt"}},
+        {"attributes": {"build_type": "opt"}},
+    )
+)
+
+
+disperse_tasks = list(
+    generate_tasks(
+        {
+            "attributes": {
+                "test_manifests": ["foo/test.ini", "bar/test.ini"],
+                "test_platform": "linux/opt",
+            }
+        },
+        {
+            "attributes": {
+                "test_manifests": ["bar/test.ini"],
+                "test_platform": "linux/opt",
+            }
+        },
+        {
+            "attributes": {
+                "test_manifests": ["bar/test.ini"],
+                "test_platform": "windows/debug",
+            }
+        },
+        {
+            "attributes": {
+                "test_manifests": ["bar/test.ini"],
+                "test_platform": "linux/opt",
+                "unittest_variant": "no-fission",
+            }
+        },
+        {
+            "attributes": {
+                "e10s": False,
+                "test_manifests": ["bar/test.ini"],
+                "test_platform": "linux/opt",
+            }
+        },
+    )
+)
+
+
+def idfn(param):
+    if isinstance(param, tuple):
+        try:
+            return param[0].__name__
+        except AttributeError:
+            return None
+    return None
+
+
+@pytest.mark.parametrize(
+    "opt,tasks,arg,expected",
+    [
+        # debug
+        pytest.param(
+            SkipUnlessDebug(),
+            default_tasks,
+            None,
+            ["task-0-label", "task-1-label", "task-2-label"],
+        ),
+        # disperse with no supplied importance
+        pytest.param(
+            DisperseGroups(),
+            disperse_tasks,
+            None,
+            [t.label for t in disperse_tasks],
+        ),
+        # disperse with low importance
+        pytest.param(
+            DisperseGroups(),
+            disperse_tasks,
+            {"bar/test.ini": "low"},
+            ["task-0-label", "task-2-label"],
+        ),
+        # disperse with medium importance
+        pytest.param(
+            DisperseGroups(),
+            disperse_tasks,
+            {"bar/test.ini": "medium"},
+            ["task-0-label", "task-1-label", "task-2-label"],
+        ),
+        # disperse with high importance
+        pytest.param(
+            DisperseGroups(),
+            disperse_tasks,
+            {"bar/test.ini": "high"},
+            ["task-0-label", "task-1-label", "task-2-label", "task-3-label"],
+        ),
+    ],
+    ids=idfn,
+)
+def test_optimization_strategy_remove(params, opt, tasks, arg, expected):
+    labels = [t.label for t in tasks if not opt.should_remove_task(t, params, arg)]
+    assert sorted(labels) == sorted(expected)
+
+
+@pytest.mark.parametrize(
+    "state,expires,expected",
+    (
+        ("completed", "2021-06-06T14:53:16.937Z", False),
+        ("completed", "2021-06-08T14:53:16.937Z", "abc"),
+        ("exception", "2021-06-08T14:53:16.937Z", False),
+        ("failed", "2021-06-08T14:53:16.937Z", False),
+    ),
+)
+def test_index_search(responses, params, state, expires, expected):
+    taskid = "abc"
+    index_path = "foo.bar.latest"
+    responses.add(
+        responses.GET,
+        f"https://firefox-ci-tc.services.mozilla.com/api/index/v1/task/{index_path}",
+        json={"taskId": taskid},
+        status=200,
+    )
+
+    responses.add(
+        responses.GET,
+        f"https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/{taskid}/status",
+        json={
+            "status": {
+                "state": state,
+                "expires": expires,
+            }
+        },
+        status=200,
+    )
+
+    opt = IndexSearch()
+    deadline = "2021-06-07T19:03:20.482Z"
+    assert opt.should_replace_task({}, params, deadline, (index_path,)) == expected
+
+
+@pytest.mark.parametrize(
+    "args,data,expected",
+    [
+        # empty
+        pytest.param(
+            (0.1,),
+            {},
+            [],
+        ),
+        # only tasks without test manifests selected
+        pytest.param(
+            (0.1,),
+            {"tasks": {"task-1-label": 0.9, "task-2-label": 0.1, "task-3-label": 0.5}},
+            ["task-2-label"],
+        ),
+        # tasks which are unknown to bugbug are selected
+        pytest.param(
+            (0.1,),
+            {
+                "tasks": {"task-1-label": 0.9, "task-3-label": 0.5},
+                "known_tasks": ["task-1-label", "task-3-label", "task-4-label"],
+            },
+            ["task-2-label"],
+        ),
+        # tasks containing groups selected
+        pytest.param(
+            (0.1,),
+            {"groups": {"foo/test.ini": 0.4}},
+            ["task-0-label"],
+        ),
+        # tasks matching "tasks" or "groups" selected
+        pytest.param(
+            (0.1,),
+            {
+                "tasks": {"task-2-label": 0.2},
+                "groups": {"foo/test.ini": 0.25, "bar/test.ini": 0.75},
+            },
+            ["task-0-label", "task-1-label", "task-2-label"],
+        ),
+        # tasks matching "tasks" or "groups" selected, when they exceed the confidence threshold
+        pytest.param(
+            (0.5,),
+            {
+                "tasks": {"task-2-label": 0.2, "task-4-label": 0.5},
+                "groups": {"foo/test.ini": 0.65, "bar/test.ini": 0.25},
+            },
+            ["task-0-label", "task-4-label"],
+        ),
+        # tasks matching "reduced_tasks" are selected, when they exceed the confidence threshold
+        pytest.param(
+            (0.7, True, True),
+            {
+                "tasks": {"task-2-label": 0.7, "task-4-label": 0.7},
+                "reduced_tasks": {"task-4-label": 0.7},
+                "groups": {"foo/test.ini": 0.75, "bar/test.ini": 0.25},
+            },
+            ["task-4-label"],
+        ),
+        # tasks matching "groups" selected, only on specific platforms.
+        pytest.param(
+            (0.1, False, False, None, 1, True),
+            {
+                "tasks": {"task-2-label": 0.2},
+                "groups": {"foo/test.ini": 0.25, "bar/test.ini": 0.75},
+                "config_groups": {
+                    "foo/test.ini": ["task-1-label", "task-0-label"],
+                    "bar/test.ini": ["task-0-label"],
+                },
+            },
+            ["task-0-label", "task-2-label"],
+        ),
+        pytest.param(
+            (0.1, False, False, None, 1, True),
+            {
+                "tasks": {"task-2-label": 0.2},
+                "groups": {"foo/test.ini": 0.25, "bar/test.ini": 0.75},
+                "config_groups": {
+                    "foo/test.ini": ["task-1-label", "task-0-label"],
+                    "bar/test.ini": ["task-1-label"],
+                },
+            },
+            ["task-0-label", "task-1-label", "task-2-label"],
+        ),
+        pytest.param(
+            (0.1, False, False, None, 1, True),
+            {
+                "tasks": {"task-2-label": 0.2},
+                "groups": {"foo/test.ini": 0.25, "bar/test.ini": 0.75},
+                "config_groups": {
+                    "foo/test.ini": ["task-1-label"],
+                    "bar/test.ini": ["task-0-label"],
+                },
+            },
+            ["task-0-label", "task-2-label"],
+        ),
+        pytest.param(
+            (0.1, False, False, None, 1, True),
+            {
+                "tasks": {"task-2-label": 0.2},
+                "groups": {"foo/test.ini": 0.25, "bar/test.ini": 0.75},
+                "config_groups": {
+                    "foo/test.ini": ["task-1-label"],
+                    "bar/test.ini": ["task-3-label"],
+                },
+            },
+            ["task-2-label"],
+        ),
+    ],
+    ids=idfn,
+)
+def test_bugbug_push_schedules(responses, params, args, data, expected):
+    query = "/push/{branch}/{head_rev}/schedules".format(**params)
+    url = BUGBUG_BASE_URL + query
+
+    responses.add(
+        responses.GET,
+        url,
+        json=data,
+        status=200,
+    )
+
+    opt = BugBugPushSchedules(*args)
+    labels = [
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    ]
+    assert sorted(labels) == sorted(expected)
+
+
+def test_bugbug_multiple_pushes(responses, params):
+    pushes = {str(pid): {"changesets": [f"c{pid}"]} for pid in range(8, 10)}
+
+    responses.add(
+        responses.GET,
+        "https://hg.mozilla.org/integration/autoland/json-pushes/?version=2&startID=8&endID=9",
+        json={"pushes": pushes},
+        status=200,
+    )
+
+    responses.add(
+        responses.GET,
+        BUGBUG_BASE_URL + "/push/{}/c9/schedules".format(params["branch"]),
+        json={
+            "tasks": {"task-2-label": 0.2, "task-4-label": 0.5},
+            "groups": {"foo/test.ini": 0.2, "bar/test.ini": 0.25},
+            "config_groups": {"foo/test.ini": ["linux-*"], "bar/test.ini": ["task-*"]},
+            "known_tasks": ["task-4-label"],
+        },
+        status=200,
+    )
+
+    # Tasks with a lower confidence don't override task with a higher one.
+    # Tasks with a higher confidence override tasks with a lower one.
+    # Known tasks are merged.
+    responses.add(
+        responses.GET,
+        BUGBUG_BASE_URL + "/push/{branch}/{head_rev}/schedules".format(**params),
+        json={
+            "tasks": {"task-2-label": 0.2, "task-4-label": 0.2},
+            "groups": {"foo/test.ini": 0.65, "bar/test.ini": 0.25},
+            "config_groups": {
+                "foo/test.ini": ["task-*"],
+                "bar/test.ini": ["windows-*"],
+            },
+            "known_tasks": ["task-1-label", "task-3-label"],
+        },
+        status=200,
+    )
+
+    params["pushlog_id"] = 10
+
+    opt = BugBugPushSchedules(0.3, False, False, False, 2)
+    labels = [
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    ]
+    assert sorted(labels) == sorted(["task-0-label", "task-2-label", "task-4-label"])
+
+    opt = BugBugPushSchedules(0.3, False, False, False, 2, True)
+    labels = [
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    ]
+    assert sorted(labels) == sorted(["task-0-label", "task-2-label", "task-4-label"])
+
+    opt = BugBugPushSchedules(0.2, False, False, False, 2, True)
+    labels = [
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    ]
+    assert sorted(labels) == sorted(
+        ["task-0-label", "task-1-label", "task-2-label", "task-4-label"]
+    )
+
+
+def test_bugbug_timeout(monkeypatch, responses, params):
+    query = "/push/{branch}/{head_rev}/schedules".format(**params)
+    url = BUGBUG_BASE_URL + query
+    responses.add(
+        responses.GET,
+        url,
+        json={"ready": False},
+        status=202,
+    )
+
+    # Make sure the test runs fast.
+    monkeypatch.setattr(time, "sleep", lambda i: None)
+
+    opt = BugBugPushSchedules(0.5)
+    with pytest.raises(BugbugTimeoutException):
+        opt.should_remove_task(default_tasks[0], params, None)
+
+
+def test_bugbug_fallback(monkeypatch, responses, params):
+    query = "/push/{branch}/{head_rev}/schedules".format(**params)
+    url = BUGBUG_BASE_URL + query
+    responses.add(
+        responses.GET,
+        url,
+        json={"ready": False},
+        status=202,
+    )
+
+    opt = BugBugPushSchedules(0.5, fallback=FALLBACK)
+
+    # Make sure the test runs fast.
+    monkeypatch.setattr(time, "sleep", lambda i: None)
+
+    def fake_should_remove_task(task, params, _):
+        return task.label == default_tasks[0].label
+
+    monkeypatch.setattr(
+        registry[FALLBACK], "should_remove_task", fake_should_remove_task
+    )
+
+    assert opt.should_remove_task(default_tasks[0], params, None)
+
+    # Make sure we don't hit bugbug more than once.
+    responses.reset()
+
+    assert not opt.should_remove_task(default_tasks[1], params, None)
+
+
+def test_backstop(params):
+    all_labels = {t.label for t in default_tasks}
+    opt = SkipUnlessBackstop()
+
+    params["backstop"] = False
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == set()
+
+    params["backstop"] = True
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == all_labels
+
+
+def test_push_interval(params):
+    all_labels = {t.label for t in default_tasks}
+    opt = SkipUnlessPushInterval(10)  # every 10th push
+
+    # Only multiples of 10 schedule tasks.
+    params["pushlog_id"] = 9
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == set()
+
+    params["pushlog_id"] = 10
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == all_labels
+
+
+def test_expanded(params):
+    all_labels = {t.label for t in default_tasks}
+    opt = registry["skip-unless-expanded"]
+
+    params["backstop"] = False
+    params["pushlog_id"] = BACKSTOP_PUSH_INTERVAL / 2
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == all_labels
+
+    params["pushlog_id"] += 1
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == set()
+
+    params["backstop"] = True
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, None)
+    }
+    assert scheduled == all_labels
+
+
+def test_project_autoland_test(monkeypatch, responses, params):
+    """Tests the behaviour of the `project.autoland["test"]` strategy on
+    various types of pushes.
+    """
+    # This is meant to test the composition of substrategies, and not the
+    # actual optimization implementations. So mock them out for simplicity.
+    monkeypatch.setattr(SkipUnlessSchedules, "should_remove_task", lambda *args: False)
+    monkeypatch.setattr(DisperseGroups, "should_remove_task", lambda *args: False)
+
+    def fake_bugbug_should_remove_task(self, task, params, importance):
+        if self.num_pushes > 1:
+            return task.label == "task-4-label"
+        return task.label in ("task-2-label", "task-3-label", "task-4-label")
+
+    monkeypatch.setattr(
+        BugBugPushSchedules, "should_remove_task", fake_bugbug_should_remove_task
+    )
+
+    opt = project.autoland["test"]
+
+    # On backstop pushes, nothing gets optimized.
+    params["backstop"] = True
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    }
+    assert scheduled == {t.label for t in default_tasks}
+
+    # On expanded pushes, some things are optimized.
+    params["backstop"] = False
+    params["pushlog_id"] = 10
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    }
+    assert scheduled == {"task-0-label", "task-1-label", "task-2-label", "task-3-label"}
+
+    # On regular pushes, more things are optimized.
+    params["pushlog_id"] = 11
+    scheduled = {
+        t.label for t in default_tasks if not opt.should_remove_task(t, params, {})
+    }
+    assert scheduled == {"task-0-label", "task-1-label"}
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_target_tasks.py b/taskcluster/gecko_taskgraph/test/test_target_tasks.py
new file mode 100644
index 0000000000..154c0f910a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_target_tasks.py
@@ -0,0 +1,371 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import contextlib
+import re
+import unittest
+
+import pytest
+from mozunit import main
+from taskgraph.graph import Graph
+from taskgraph.task import Task
+from taskgraph.taskgraph import TaskGraph
+
+from gecko_taskgraph import target_tasks, try_option_syntax
+
+
+class FakeTryOptionSyntax:
+    def __init__(self, message, task_graph, graph_config):
+        self.trigger_tests = 0
+        self.talos_trigger_tests = 0
+        self.raptor_trigger_tests = 0
+        self.notifications = None
+        self.env = []
+        self.profile = False
+        self.tag = None
+        self.no_retry = False
+
+    def task_matches(self, task):
+        return "at-at" in task.attributes
+
+
+class TestTargetTasks(unittest.TestCase):
+    def default_matches_project(self, run_on_projects, project):
+        return self.default_matches(
+            attributes={
+                "run_on_projects": run_on_projects,
+            },
+            parameters={
+                "project": project,
+                "hg_branch": "default",
+            },
+        )
+
+    def default_matches_hg_branch(self, run_on_hg_branches, hg_branch):
+        attributes = {"run_on_projects": ["all"]}
+        if run_on_hg_branches is not None:
+            attributes["run_on_hg_branches"] = run_on_hg_branches
+
+        return self.default_matches(
+            attributes=attributes,
+            parameters={
+                "project": "mozilla-central",
+                "hg_branch": hg_branch,
+            },
+        )
+
+    def default_matches(self, attributes, parameters):
+        method = target_tasks.get_method("default")
+        graph = TaskGraph(
+            tasks={
+                "a": Task(kind="build", label="a", attributes=attributes, task={}),
+            },
+            graph=Graph(nodes={"a"}, edges=set()),
+        )
+        return "a" in method(graph, parameters, {})
+
+    def test_default_all(self):
+        """run_on_projects=[all] includes release, integration, and other projects"""
+        self.assertTrue(self.default_matches_project(["all"], "mozilla-central"))
+        self.assertTrue(self.default_matches_project(["all"], "baobab"))
+
+    def test_default_integration(self):
+        """run_on_projects=[integration] includes integration projects"""
+        self.assertFalse(
+            self.default_matches_project(["integration"], "mozilla-central")
+        )
+        self.assertFalse(self.default_matches_project(["integration"], "baobab"))
+
+    def test_default_release(self):
+        """run_on_projects=[release] includes release projects"""
+        self.assertTrue(self.default_matches_project(["release"], "mozilla-central"))
+        self.assertFalse(self.default_matches_project(["release"], "baobab"))
+
+    def test_default_nothing(self):
+        """run_on_projects=[] includes nothing"""
+        self.assertFalse(self.default_matches_project([], "mozilla-central"))
+        self.assertFalse(self.default_matches_project([], "baobab"))
+
+    def test_default_hg_branch(self):
+        self.assertTrue(self.default_matches_hg_branch(None, "default"))
+        self.assertTrue(self.default_matches_hg_branch(None, "GECKOVIEW_62_RELBRANCH"))
+
+        self.assertFalse(self.default_matches_hg_branch([], "default"))
+        self.assertFalse(self.default_matches_hg_branch([], "GECKOVIEW_62_RELBRANCH"))
+
+        self.assertTrue(self.default_matches_hg_branch(["all"], "default"))
+        self.assertTrue(
+            self.default_matches_hg_branch(["all"], "GECKOVIEW_62_RELBRANCH")
+        )
+
+        self.assertTrue(self.default_matches_hg_branch(["default"], "default"))
+        self.assertTrue(self.default_matches_hg_branch([r"default"], "default"))
+        self.assertFalse(
+            self.default_matches_hg_branch([r"default"], "GECKOVIEW_62_RELBRANCH")
+        )
+
+        self.assertTrue(
+            self.default_matches_hg_branch(
+                ["GECKOVIEW_62_RELBRANCH"], "GECKOVIEW_62_RELBRANCH"
+            )
+        )
+        self.assertTrue(
+            self.default_matches_hg_branch(
+                [r"GECKOVIEW_\d+_RELBRANCH"], "GECKOVIEW_62_RELBRANCH"
+            )
+        )
+        self.assertTrue(
+            self.default_matches_hg_branch(
+                [r"GECKOVIEW_\d+_RELBRANCH"], "GECKOVIEW_62_RELBRANCH"
+            )
+        )
+        self.assertFalse(
+            self.default_matches_hg_branch([r"GECKOVIEW_\d+_RELBRANCH"], "default")
+        )
+
+    def make_task_graph(self):
+        tasks = {
+            "a": Task(kind=None, label="a", attributes={}, task={}),
+            "b": Task(kind=None, label="b", attributes={"at-at": "yep"}, task={}),
+            "c": Task(
+                kind=None, label="c", attributes={"run_on_projects": ["try"]}, task={}
+            ),
+        }
+        graph = Graph(nodes=set("abc"), edges=set())
+        return TaskGraph(tasks, graph)
+
+    @contextlib.contextmanager
+    def fake_TryOptionSyntax(self):
+        orig_TryOptionSyntax = try_option_syntax.TryOptionSyntax
+        try:
+            try_option_syntax.TryOptionSyntax = FakeTryOptionSyntax
+            yield
+        finally:
+            try_option_syntax.TryOptionSyntax = orig_TryOptionSyntax
+
+    def test_empty_try(self):
+        "try_mode = None runs nothing"
+        tg = self.make_task_graph()
+        method = target_tasks.get_method("try_tasks")
+        params = {
+            "try_mode": None,
+            "project": "try",
+            "message": "",
+        }
+        # only runs the task with run_on_projects: try
+        self.assertEqual(method(tg, params, {}), [])
+
+    def test_try_option_syntax(self):
+        "try_mode = try_option_syntax uses TryOptionSyntax"
+        tg = self.make_task_graph()
+        method = target_tasks.get_method("try_tasks")
+        with self.fake_TryOptionSyntax():
+            params = {
+                "try_mode": "try_option_syntax",
+                "message": "try: -p all",
+            }
+            self.assertEqual(method(tg, params, {}), ["b"])
+
+    def test_try_task_config(self):
+        "try_mode = try_task_config uses the try config"
+        tg = self.make_task_graph()
+        method = target_tasks.get_method("try_tasks")
+        params = {
+            "try_mode": "try_task_config",
+            "try_task_config": {"tasks": ["a"]},
+        }
+        self.assertEqual(method(tg, params, {}), ["a"])
+
+
+# tests for specific filters
+
+
+@pytest.mark.parametrize(
+    "name,params,expected",
+    (
+        pytest.param(
+            "filter_tests_without_manifests",
+            {
+                "task": Task(kind="test", label="a", attributes={}, task={}),
+                "parameters": None,
+            },
+            True,
+            id="filter_tests_without_manifests_not_in_attributes",
+        ),
+        pytest.param(
+            "filter_tests_without_manifests",
+            {
+                "task": Task(
+                    kind="test",
+                    label="a",
+                    attributes={"test_manifests": ["foo"]},
+                    task={},
+                ),
+                "parameters": None,
+            },
+            True,
+            id="filter_tests_without_manifests_has_test_manifests",
+        ),
+        pytest.param(
+            "filter_tests_without_manifests",
+            {
+                "task": Task(
+                    kind="build",
+                    label="a",
+                    attributes={"test_manifests": None},
+                    task={},
+                ),
+                "parameters": None,
+            },
+            True,
+            id="filter_tests_without_manifests_not_a_test",
+        ),
+        pytest.param(
+            "filter_tests_without_manifests",
+            {
+                "task": Task(
+                    kind="test", label="a", attributes={"test_manifests": None}, task={}
+                ),
+                "parameters": None,
+            },
+            False,
+            id="filter_tests_without_manifests_has_no_test_manifests",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("build")],
+                "mode": "include",
+            },
+            True,
+            id="filter_regex_simple_include",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("linux(.+)debug")],
+                "mode": "include",
+            },
+            True,
+            id="filter_regex_re_include",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("nothing"), re.compile("linux(.+)debug")],
+                "mode": "include",
+            },
+            True,
+            id="filter_regex_re_include_multiple",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("build")],
+                "mode": "exclude",
+            },
+            False,
+            id="filter_regex_simple_exclude",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("linux(.+)debug")],
+                "mode": "exclude",
+            },
+            False,
+            id="filter_regex_re_exclude",
+        ),
+        pytest.param(
+            "filter_by_regex",
+            {
+                "task_label": "build-linux64-debug",
+                "regexes": [re.compile("linux(.+)debug"), re.compile("nothing")],
+                "mode": "exclude",
+            },
+            False,
+            id="filter_regex_re_exclude_multiple",
+        ),
+        pytest.param(
+            "filter_unsupported_artifact_builds",
+            {
+                "task": Task(
+                    kind="test",
+                    label="a",
+                    attributes={"supports-artifact-builds": False},
+                    task={},
+                ),
+                "parameters": {
+                    "try_task_config": {
+                        "use-artifact-builds": False,
+                    },
+                },
+            },
+            True,
+            id="filter_unsupported_artifact_builds_no_artifact_builds",
+        ),
+        pytest.param(
+            "filter_unsupported_artifact_builds",
+            {
+                "task": Task(
+                    kind="test",
+                    label="a",
+                    attributes={"supports-artifact-builds": False},
+                    task={},
+                ),
+                "parameters": {
+                    "try_task_config": {
+                        "use-artifact-builds": True,
+                    },
+                },
+            },
+            False,
+            id="filter_unsupported_artifact_builds_removed",
+        ),
+        pytest.param(
+            "filter_unsupported_artifact_builds",
+            {
+                "task": Task(
+                    kind="test",
+                    label="a",
+                    attributes={"supports-artifact-builds": True},
+                    task={},
+                ),
+                "parameters": {
+                    "try_task_config": {
+                        "use-artifact-builds": True,
+                    },
+                },
+            },
+            True,
+            id="filter_unsupported_artifact_builds_not_removed",
+        ),
+        pytest.param(
+            "filter_unsupported_artifact_builds",
+            {
+                "task": Task(kind="test", label="a", attributes={}, task={}),
+                "parameters": {
+                    "try_task_config": {
+                        "use-artifact-builds": True,
+                    },
+                },
+            },
+            True,
+            id="filter_unsupported_artifact_builds_not_removed",
+        ),
+    ),
+)
+def test_filters(name, params, expected):
+    func = getattr(target_tasks, name)
+    assert func(**params) is expected
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_taskcluster_yml.py b/taskcluster/gecko_taskgraph/test/test_taskcluster_yml.py
new file mode 100644
index 0000000000..cdf94ec3e1
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_taskcluster_yml.py
@@ -0,0 +1,145 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import pprint
+import unittest
+
+import jsone
+import slugid
+from mozunit import main
+from taskgraph.util.time import current_json_time
+from taskgraph.util.yaml import load_yaml
+
+from gecko_taskgraph import GECKO
+
+
+class TestTaskclusterYml(unittest.TestCase):
+    @property
+    def taskcluster_yml(self):
+        return load_yaml(GECKO, ".taskcluster.yml")
+
+    def test_push(self):
+        context = {
+            "tasks_for": "hg-push",
+            "push": {
+                "revision": "e8d2d9aff5026ef1f1777b781b47fdcbdb9d8f20",
+                "base_revision": "e8aebe488b2f2e567940577de25013d00e818f7c",
+                "owner": "dustin@mozilla.com",
+                "pushlog_id": 1556565286,
+                "pushdate": 112957,
+            },
+            "repository": {
+                "url": "https://hg.mozilla.org/mozilla-central",
+                "project": "mozilla-central",
+                "level": "3",
+            },
+            "ownTaskId": slugid.nice(),
+        }
+        rendered = jsone.render(self.taskcluster_yml, context)
+        pprint.pprint(rendered)
+        self.assertEqual(
+            rendered["tasks"][0]["metadata"]["name"], "Gecko Decision Task"
+        )
+        self.assertIn("matrixBody", rendered["tasks"][0]["extra"]["notify"])
+
+    def test_push_non_mc(self):
+        context = {
+            "tasks_for": "hg-push",
+            "push": {
+                "revision": "e8d2d9aff5026ef1f1777b781b47fdcbdb9d8f20",
+                "base_revision": "e8aebe488b2f2e567940577de25013d00e818f7c",
+                "owner": "dustin@mozilla.com",
+                "pushlog_id": 1556565286,
+                "pushdate": 112957,
+            },
+            "repository": {
+                "url": "https://hg.mozilla.org/releases/mozilla-beta",
+                "project": "mozilla-beta",
+                "level": "3",
+            },
+            "ownTaskId": slugid.nice(),
+        }
+        rendered = jsone.render(self.taskcluster_yml, context)
+        pprint.pprint(rendered)
+        self.assertEqual(
+            rendered["tasks"][0]["metadata"]["name"], "Gecko Decision Task"
+        )
+        self.assertNotIn("matrixBody", rendered["tasks"][0]["extra"]["notify"])
+
+    def test_cron(self):
+        context = {
+            "tasks_for": "cron",
+            "repository": {
+                "url": "https://hg.mozilla.org/mozilla-central",
+                "project": "mozilla-central",
+                "level": 3,
+            },
+            "push": {
+                "revision": "e8aebe488b2f2e567940577de25013d00e818f7c",
+                "base_revision": "54cbb3745cdb9a8aa0a4428d405b3b2e1c7d13c2",
+                "pushlog_id": -1,
+                "pushdate": 0,
+                "owner": "cron",
+            },
+            "cron": {
+                "task_id": "<cron task id>",
+                "job_name": "test",
+                "job_symbol": "T",
+                "quoted_args": "abc def",
+            },
+            "now": current_json_time(),
+            "ownTaskId": slugid.nice(),
+        }
+        rendered = jsone.render(self.taskcluster_yml, context)
+        pprint.pprint(rendered)
+        self.assertEqual(
+            rendered["tasks"][0]["metadata"]["name"], "Decision Task for cron job test"
+        )
+
+    def test_action(self):
+        context = {
+            "tasks_for": "action",
+            "repository": {
+                "url": "https://hg.mozilla.org/mozilla-central",
+                "project": "mozilla-central",
+                "level": 3,
+            },
+            "push": {
+                "revision": "e8d2d9aff5026ef1f1777b781b47fdcbdb9d8f20",
+                "base_revision": "e8aebe488b2f2e567940577de25013d00e818f7c",
+                "owner": "dustin@mozilla.com",
+                "pushlog_id": 1556565286,
+                "pushdate": 112957,
+            },
+            "action": {
+                "name": "test-action",
+                "title": "Test Action",
+                "description": "Just testing",
+                "taskGroupId": slugid.nice(),
+                "symbol": "t",
+                "repo_scope": "assume:repo:hg.mozilla.org/try:action:generic",
+                "cb_name": "test_action",
+            },
+            "input": {},
+            "parameters": {},
+            "now": current_json_time(),
+            "taskId": slugid.nice(),
+            "ownTaskId": slugid.nice(),
+            "clientId": "testing/testing/testing",
+        }
+        rendered = jsone.render(self.taskcluster_yml, context)
+        pprint.pprint(rendered)
+        self.assertEqual(
+            rendered["tasks"][0]["metadata"]["name"], "Action: Test Action"
+        )
+
+    def test_unknown(self):
+        context = {"tasks_for": "bitkeeper-push"}
+        rendered = jsone.render(self.taskcluster_yml, context)
+        pprint.pprint(rendered)
+        self.assertEqual(rendered["tasks"], [])
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_transforms_job.py b/taskcluster/gecko_taskgraph/test/test_transforms_job.py
new file mode 100644
index 0000000000..8bf85dcf62
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_transforms_job.py
@@ -0,0 +1,150 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Tests for the 'job' transform subsystem.
+"""
+
+
+import os
+from copy import deepcopy
+
+import pytest
+from mozunit import main
+from taskgraph.config import load_graph_config
+from taskgraph.transforms.base import TransformConfig
+from taskgraph.util.schema import Schema, validate_schema
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.test.conftest import FakeParameters
+from gecko_taskgraph.transforms import job
+from gecko_taskgraph.transforms.job import run_task  # noqa: F401
+from gecko_taskgraph.transforms.job.common import add_cache
+from gecko_taskgraph.transforms.task import payload_builders
+
+here = os.path.abspath(os.path.dirname(__file__))
+
+
+TASK_DEFAULTS = {
+    "description": "fake description",
+    "label": "fake-task-label",
+    "run": {
+        "using": "run-task",
+    },
+}
+
+
+@pytest.fixture(scope="module")
+def config():
+    graph_config = load_graph_config(os.path.join(GECKO, "taskcluster", "ci"))
+    params = FakeParameters(
+        {
+            "base_repository": "http://hg.example.com",
+            "head_repository": "http://hg.example.com",
+            "head_rev": "abcdef",
+            "level": 1,
+            "project": "example",
+        }
+    )
+    return TransformConfig(
+        "job_test", here, {}, params, {}, graph_config, write_artifacts=False
+    )
+
+
+@pytest.fixture()
+def transform(monkeypatch, config):
+    """Run the job transforms on the specified task but return the inputs to
+    `configure_taskdesc_for_run` without executing it.
+
+    This gives test functions an easy way to generate the inputs required for
+    many of the `run_using` subsystems.
+    """
+
+    def inner(task_input):
+        task = deepcopy(TASK_DEFAULTS)
+        task.update(task_input)
+        frozen_args = []
+
+        def _configure_taskdesc_for_run(*args):
+            frozen_args.extend(args)
+
+        monkeypatch.setattr(
+            job, "configure_taskdesc_for_run", _configure_taskdesc_for_run
+        )
+
+        for _ in job.transforms(config, [task]):
+            # This forces the generator to be evaluated
+            pass
+
+        return frozen_args
+
+    return inner
+
+
+@pytest.mark.parametrize(
+    "task",
+    [
+        {"worker-type": "b-linux"},
+        {"worker-type": "t-win10-64-hw"},
+    ],
+    ids=lambda t: t["worker-type"],
+)
+def test_worker_caches(task, transform):
+    config, job, taskdesc, impl = transform(task)
+    add_cache(job, taskdesc, "cache1", "/cache1")
+    add_cache(job, taskdesc, "cache2", "/cache2", skip_untrusted=True)
+
+    if impl not in ("docker-worker", "generic-worker"):
+        pytest.xfail(f"caches not implemented for '{impl}'")
+
+    key = "caches" if impl == "docker-worker" else "mounts"
+    assert key in taskdesc["worker"]
+    assert len(taskdesc["worker"][key]) == 2
+
+    # Create a new schema object with just the part relevant to caches.
+    partial_schema = Schema(payload_builders[impl].schema.schema[key])
+    validate_schema(partial_schema, taskdesc["worker"][key], "validation error")
+
+
+@pytest.mark.parametrize(
+    "workerfn", [fn for fn, *_ in job.registry["run-task"].values()]
+)
+@pytest.mark.parametrize(
+    "task",
+    (
+        {
+            "worker-type": "b-linux",
+            "run": {
+                "checkout": True,
+                "comm-checkout": False,
+                "command": "echo '{output}'",
+                "command-context": {"output": "hello", "extra": None},
+                "run-as-root": False,
+                "sparse-profile": False,
+                "tooltool-downloads": False,
+            },
+        },
+    ),
+)
+def test_run_task_command_context(task, transform, workerfn):
+    config, job_, taskdesc, _ = transform(task)
+    job_ = deepcopy(job_)
+
+    def assert_cmd(expected):
+        cmd = taskdesc["worker"]["command"]
+        while isinstance(cmd, list):
+            cmd = cmd[-1]
+        assert cmd == expected
+
+    workerfn(config, job_, taskdesc)
+    assert_cmd("echo 'hello'")
+
+    job_copy = job_.copy()
+    del job_copy["run"]["command-context"]
+    workerfn(config, job_copy, taskdesc)
+    assert_cmd("echo '{output}'")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_transforms_test.py b/taskcluster/gecko_taskgraph/test/test_transforms_test.py
new file mode 100644
index 0000000000..2b90fed3e7
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_transforms_test.py
@@ -0,0 +1,328 @@
+# Any copyright is dedicated to the Public Domain.
+# https://creativecommons.org/publicdomain/zero/1.0/
+"""
+Tests for the 'tests.py' transforms
+"""
+
+import hashlib
+import json
+from functools import partial
+from pprint import pprint
+
+import mozunit
+import pytest
+
+from gecko_taskgraph.transforms import test as test_transforms
+
+
+@pytest.fixture
+def make_test_task():
+    """Create a test task definition with required default values."""
+
+    def inner(**extra):
+        task = {
+            "attributes": {},
+            "build-platform": "linux64",
+            "mozharness": {"extra-options": []},
+            "test-platform": "linux64",
+            "treeherder-symbol": "g(t)",
+            "try-name": "task",
+        }
+        task.update(extra)
+        return task
+
+    return inner
+
+
+def test_split_variants(monkeypatch, run_full_config_transform, make_test_task):
+    # mock out variant definitions
+    monkeypatch.setattr(
+        test_transforms.variant,
+        "TEST_VARIANTS",
+        {
+            "foo": {
+                "description": "foo variant",
+                "suffix": "foo",
+                "component": "foo bar",
+                "expiration": "never",
+                "merge": {
+                    "mozharness": {
+                        "extra-options": [
+                            "--setpref=foo=1",
+                        ],
+                    },
+                },
+            },
+            "bar": {
+                "description": "bar variant",
+                "suffix": "bar",
+                "component": "foo bar",
+                "expiration": "never",
+                "when": {
+                    "$eval": "task['test-platform'][:5] == 'linux'",
+                },
+                "merge": {
+                    "mozharness": {
+                        "extra-options": [
+                            "--setpref=bar=1",
+                        ],
+                    },
+                },
+                "replace": {"tier": 2},
+            },
+        },
+    )
+
+    def make_expected(variant):
+        """Helper to generate expected tasks."""
+        return make_test_task(
+            **{
+                "attributes": {"unittest_variant": variant},
+                "description": f"{variant} variant",
+                "mozharness": {
+                    "extra-options": [f"--setpref={variant}=1"],
+                },
+                "treeherder-symbol": f"g-{variant}(t)",
+                "variant-suffix": f"-{variant}",
+            }
+        )
+
+    run_split_variants = partial(
+        run_full_config_transform, test_transforms.variant.split_variants
+    )
+
+    # test no variants
+    input_task = make_test_task(
+        **{
+            "run-without-variant": True,
+        }
+    )
+    tasks = list(run_split_variants(input_task))
+    assert len(tasks) == 1
+    assert tasks[0] == input_task
+
+    # test variants are split into expected tasks
+    input_task = make_test_task(
+        **{
+            "run-without-variant": True,
+            "variants": ["foo", "bar"],
+        }
+    )
+    tasks = list(run_split_variants(input_task))
+    assert len(tasks) == 3
+    assert tasks[0] == make_test_task()
+    assert tasks[1] == make_expected("foo")
+
+    expected = make_expected("bar")
+    expected["tier"] = 2
+    assert tasks[2] == expected
+
+    # test composite variants
+    input_task = make_test_task(
+        **{
+            "run-without-variant": True,
+            "variants": ["foo+bar"],
+        }
+    )
+    tasks = list(run_split_variants(input_task))
+    assert len(tasks) == 2
+    assert tasks[1]["attributes"]["unittest_variant"] == "foo+bar"
+    assert tasks[1]["mozharness"]["extra-options"] == [
+        "--setpref=foo=1",
+        "--setpref=bar=1",
+    ]
+    assert tasks[1]["treeherder-symbol"] == "g-foo-bar(t)"
+
+    # test 'when' filter
+    input_task = make_test_task(
+        **{
+            "run-without-variant": True,
+            # this should cause task to be filtered out of 'bar' and 'foo+bar' variants
+            "test-platform": "windows",
+            "variants": ["foo", "bar", "foo+bar"],
+        }
+    )
+    tasks = list(run_split_variants(input_task))
+    assert len(tasks) == 2
+    assert "unittest_variant" not in tasks[0]["attributes"]
+    assert tasks[1]["attributes"]["unittest_variant"] == "foo"
+
+    # test 'run-without-variants=False'
+    input_task = make_test_task(
+        **{
+            "run-without-variant": False,
+            "variants": ["foo"],
+        }
+    )
+    tasks = list(run_split_variants(input_task))
+    assert len(tasks) == 1
+    assert tasks[0]["attributes"]["unittest_variant"] == "foo"
+
+
+@pytest.mark.parametrize(
+    "task,expected",
+    (
+        pytest.param(
+            {
+                "attributes": {"unittest_variant": "webrender-sw+1proc"},
+                "test-platform": "linux1804-64-clang-trunk-qr/opt",
+            },
+            {
+                "platform": {
+                    "arch": "64",
+                    "os": {
+                        "name": "linux",
+                        "version": "1804",
+                    },
+                },
+                "build": {
+                    "type": "opt",
+                    "clang-trunk": True,
+                },
+                "runtime": {
+                    "1proc": True,
+                    "webrender-sw": True,
+                },
+            },
+            id="linux",
+        ),
+        pytest.param(
+            {
+                "attributes": {},
+                "test-platform": "linux2204-64-wayland-shippable/opt",
+            },
+            {
+                "platform": {
+                    "arch": "64",
+                    "display": "wayland",
+                    "os": {
+                        "name": "linux",
+                        "version": "2204",
+                    },
+                },
+                "build": {
+                    "type": "opt",
+                    "shippable": True,
+                },
+                "runtime": {},
+            },
+            id="linux wayland shippable",
+        ),
+        pytest.param(
+            {
+                "attributes": {},
+                "test-platform": "android-hw-a51-11-0-arm7-shippable-qr/opt",
+            },
+            {
+                "platform": {
+                    "arch": "arm7",
+                    "device": "a51",
+                    "os": {
+                        "name": "android",
+                        "version": "11.0",
+                    },
+                },
+                "build": {
+                    "type": "opt",
+                    "shippable": True,
+                },
+                "runtime": {},
+            },
+            id="android",
+        ),
+        pytest.param(
+            {
+                "attributes": {},
+                "test-platform": "windows10-64-2004-ref-hw-2017-ccov/debug",
+            },
+            {
+                "platform": {
+                    "arch": "64",
+                    "machine": "ref-hw-2017",
+                    "os": {
+                        "build": "2004",
+                        "name": "windows",
+                        "version": "10",
+                    },
+                },
+                "build": {
+                    "type": "debug",
+                    "ccov": True,
+                },
+                "runtime": {},
+            },
+            id="windows",
+        ),
+    ),
+)
+def test_set_test_setting(run_transform, task, expected):
+    # add hash to 'expected'
+    expected["_hash"] = hashlib.sha256(
+        json.dumps(expected, sort_keys=True).encode("utf-8")
+    ).hexdigest()[:12]
+
+    task = list(run_transform(test_transforms.other.set_test_setting, task))[0]
+    assert "test-setting" in task
+    assert task["test-setting"] == expected
+
+
+def assert_spi_not_disabled(task):
+    extra_options = task["mozharness"]["extra-options"]
+    # The pref to enable this gets set outside of this transform, so only
+    # bother asserting that the pref to disable does not exist.
+    assert (
+        "--setpref=media.peerconnection.mtransport_process=false" not in extra_options
+    )
+    assert "--setpref=network.process.enabled=false" not in extra_options
+
+
+def assert_spi_disabled(task):
+    extra_options = task["mozharness"]["extra-options"]
+    assert "--setpref=media.peerconnection.mtransport_process=false" in extra_options
+    assert "--setpref=media.peerconnection.mtransport_process=true" not in extra_options
+    assert "--setpref=network.process.enabled=false" in extra_options
+    assert "--setpref=network.process.enabled=true" not in extra_options
+
+
+@pytest.mark.parametrize(
+    "task,callback",
+    (
+        pytest.param(
+            {"attributes": {"unittest_variant": "socketprocess"}},
+            assert_spi_not_disabled,
+            id="socketprocess",
+        ),
+        pytest.param(
+            {
+                "attributes": {"unittest_variant": "socketprocess_networking"},
+            },
+            assert_spi_not_disabled,
+            id="socketprocess_networking",
+        ),
+        pytest.param({}, assert_spi_disabled, id="no variant"),
+        pytest.param(
+            {"suite": "cppunit", "attributes": {"unittest_variant": "socketprocess"}},
+            assert_spi_not_disabled,
+            id="excluded suite",
+        ),
+        pytest.param(
+            {"attributes": {"unittest_variant": "no-fission+socketprocess"}},
+            assert_spi_not_disabled,
+            id="composite variant",
+        ),
+    ),
+)
+def test_ensure_spi_disabled_on_all_but_spi(
+    make_test_task, run_transform, task, callback
+):
+    task.setdefault("suite", "mochitest-plain")
+    task = make_test_task(**task)
+    task = list(
+        run_transform(test_transforms.other.ensure_spi_disabled_on_all_but_spi, task)
+    )[0]
+    pprint(task)
+    callback(task)
+
+
+if __name__ == "__main__":
+    mozunit.main()
diff --git a/taskcluster/gecko_taskgraph/test/test_try_option_syntax.py b/taskcluster/gecko_taskgraph/test/test_try_option_syntax.py
new file mode 100644
index 0000000000..a37de53378
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_try_option_syntax.py
@@ -0,0 +1,430 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import unittest
+
+from mozunit import main
+from taskgraph.graph import Graph
+from taskgraph.task import Task
+from taskgraph.taskgraph import TaskGraph
+
+from gecko_taskgraph.try_option_syntax import TryOptionSyntax, parse_message
+
+
+def unittest_task(n, tp, bt="opt"):
+    return (
+        n,
+        Task(
+            "test",
+            n,
+            {
+                "unittest_try_name": n,
+                "test_platform": tp.split("/")[0],
+                "build_type": bt,
+            },
+            {},
+        ),
+    )
+
+
+def talos_task(n, tp, bt="opt"):
+    return (
+        n,
+        Task(
+            "test",
+            n,
+            {
+                "talos_try_name": n,
+                "test_platform": tp.split("/")[0],
+                "build_type": bt,
+            },
+            {},
+        ),
+    )
+
+
+tasks = {
+    k: v
+    for k, v in [
+        unittest_task("mochitest-browser-chrome", "linux/opt"),
+        unittest_task("mochitest-browser-chrome-e10s", "linux64/opt"),
+        unittest_task("mochitest-chrome", "linux/debug", "debug"),
+        unittest_task("mochitest-webgl1-core", "linux/debug", "debug"),
+        unittest_task("mochitest-webgl1-ext", "linux/debug", "debug"),
+        unittest_task("mochitest-webgl2-core", "linux/debug", "debug"),
+        unittest_task("mochitest-webgl2-ext", "linux/debug", "debug"),
+        unittest_task("mochitest-webgl2-deqp", "linux/debug", "debug"),
+        unittest_task("extra1", "linux", "debug/opt"),
+        unittest_task("extra2", "win32/opt"),
+        unittest_task("crashtest-e10s", "linux/other"),
+        unittest_task("gtest", "linux64/asan"),
+        talos_task("dromaeojs", "linux64/psan"),
+        unittest_task("extra3", "linux/opt"),
+        unittest_task("extra4", "linux64/debug", "debug"),
+        unittest_task("extra5", "linux/this"),
+        unittest_task("extra6", "linux/that"),
+        unittest_task("extra7", "linux/other"),
+        unittest_task("extra8", "linux64/asan"),
+        talos_task("extra9", "linux64/psan"),
+    ]
+}
+
+RIDEALONG_BUILDS = {
+    "linux": ["linux-ridealong"],
+    "linux64": ["linux64-ridealong"],
+}
+
+GRAPH_CONFIG = {
+    "try": {"ridealong-builds": RIDEALONG_BUILDS},
+}
+
+for r in RIDEALONG_BUILDS.values():
+    tasks.update({k: v for k, v in [unittest_task(n + "-test", n) for n in r]})
+
+unittest_tasks = {k: v for k, v in tasks.items() if "unittest_try_name" in v.attributes}
+talos_tasks = {k: v for k, v in tasks.items() if "talos_try_name" in v.attributes}
+graph_with_jobs = TaskGraph(tasks, Graph(set(tasks), set()))
+
+
+class TestTryOptionSyntax(unittest.TestCase):
+    def test_unknown_args(self):
+        "unknown arguments are ignored"
+        parameters = parse_message("try: --doubledash -z extra")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        # equilvant to "try:"..
+        self.assertEqual(tos.build_types, [])
+        self.assertEqual(tos.jobs, [])
+
+    def test_apostrophe_in_message(self):
+        "apostrophe does not break parsing"
+        parameters = parse_message("Increase spammy log's log level. try: -b do")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["debug", "opt"])
+
+    def test_b_do(self):
+        "-b do should produce both build_types"
+        parameters = parse_message("try: -b do")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["debug", "opt"])
+
+    def test_b_d(self):
+        "-b d should produce build_types=['debug']"
+        parameters = parse_message("try: -b d")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["debug"])
+
+    def test_b_o(self):
+        "-b o should produce build_types=['opt']"
+        parameters = parse_message("try: -b o")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["opt"])
+
+    def test_build_o(self):
+        "--build o should produce build_types=['opt']"
+        parameters = parse_message("try: --build o")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["opt"])
+
+    def test_b_dx(self):
+        "-b dx should produce build_types=['debug'], silently ignoring the x"
+        parameters = parse_message("try: -b dx")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.build_types), ["debug"])
+
+    def test_j_job(self):
+        "-j somejob sets jobs=['somejob']"
+        parameters = parse_message("try: -j somejob")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.jobs), ["somejob"])
+
+    def test_j_jobs(self):
+        "-j job1,job2 sets jobs=['job1', 'job2']"
+        parameters = parse_message("try: -j job1,job2")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.jobs), ["job1", "job2"])
+
+    def test_j_all(self):
+        "-j all sets jobs=None"
+        parameters = parse_message("try: -j all")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.jobs, None)
+
+    def test_j_twice(self):
+        "-j job1 -j job2 sets jobs=job1, job2"
+        parameters = parse_message("try: -j job1 -j job2")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.jobs), sorted(["job1", "job2"]))
+
+    def test_p_all(self):
+        "-p all sets platforms=None"
+        parameters = parse_message("try: -p all")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.platforms, None)
+
+    def test_p_linux(self):
+        "-p linux sets platforms=['linux', 'linux-ridealong']"
+        parameters = parse_message("try: -p linux")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.platforms, ["linux", "linux-ridealong"])
+
+    def test_p_linux_win32(self):
+        "-p linux,win32 sets platforms=['linux', 'linux-ridealong', 'win32']"
+        parameters = parse_message("try: -p linux,win32")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(sorted(tos.platforms), ["linux", "linux-ridealong", "win32"])
+
+    def test_p_expands_ridealongs(self):
+        "-p linux,linux64 includes the RIDEALONG_BUILDS"
+        parameters = parse_message("try: -p linux,linux64")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        platforms = set(["linux"] + RIDEALONG_BUILDS["linux"])
+        platforms |= set(["linux64"] + RIDEALONG_BUILDS["linux64"])
+        self.assertEqual(sorted(tos.platforms), sorted(platforms))
+
+    def test_u_none(self):
+        "-u none sets unittests=[]"
+        parameters = parse_message("try: -u none")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.unittests, [])
+
+    def test_u_all(self):
+        "-u all sets unittests=[..whole list..]"
+        parameters = parse_message("try: -u all")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.unittests, [{"test": t} for t in sorted(unittest_tasks)])
+
+    def test_u_single(self):
+        "-u mochitest-webgl1-core sets unittests=[mochitest-webgl1-core]"
+        parameters = parse_message("try: -u mochitest-webgl1-core")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.unittests, [{"test": "mochitest-webgl1-core"}])
+
+    def test_u_alias(self):
+        "-u mochitest-gl sets unittests=[mochitest-webgl*]"
+        parameters = parse_message("try: -u mochitest-gl")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            tos.unittests,
+            [
+                {"test": t}
+                for t in [
+                    "mochitest-webgl1-core",
+                    "mochitest-webgl1-ext",
+                    "mochitest-webgl2-core",
+                    "mochitest-webgl2-deqp",
+                    "mochitest-webgl2-ext",
+                ]
+            ],
+        )
+
+    def test_u_multi_alias(self):
+        "-u e10s sets unittests=[all e10s unittests]"
+        parameters = parse_message("try: -u e10s")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            tos.unittests, [{"test": t} for t in sorted(unittest_tasks) if "e10s" in t]
+        )
+
+    def test_u_commas(self):
+        "-u mochitest-webgl1-core,gtest sets unittests=both"
+        parameters = parse_message("try: -u mochitest-webgl1-core,gtest")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            tos.unittests,
+            [
+                {"test": "gtest"},
+                {"test": "mochitest-webgl1-core"},
+            ],
+        )
+
+    def test_u_chunks(self):
+        "-u gtest-3,gtest-4 selects the third and fourth chunk of gtest"
+        parameters = parse_message("try: -u gtest-3,gtest-4")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            sorted(tos.unittests),
+            sorted(
+                [
+                    {"test": "gtest", "only_chunks": set("34")},
+                ]
+            ),
+        )
+
+    def test_u_platform(self):
+        "-u gtest[linux] selects the linux platform for gtest"
+        parameters = parse_message("try: -u gtest[linux]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            sorted(tos.unittests),
+            sorted(
+                [
+                    {"test": "gtest", "platforms": ["linux"]},
+                ]
+            ),
+        )
+
+    def test_u_platforms(self):
+        "-u gtest[linux,win32] selects the linux and win32 platforms for gtest"
+        parameters = parse_message("try: -u gtest[linux,win32]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            sorted(tos.unittests),
+            sorted(
+                [
+                    {"test": "gtest", "platforms": ["linux", "win32"]},
+                ]
+            ),
+        )
+
+    def test_u_platforms_pretty(self):
+        """-u gtest[Ubuntu] selects the linux, linux64 and linux64-asan
+        platforms for gtest"""
+        parameters = parse_message("try: -u gtest[Ubuntu]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            sorted(tos.unittests),
+            sorted(
+                [
+                    {
+                        "test": "gtest",
+                        "platforms": [
+                            "linux32",
+                            "linux64",
+                            "linux64-asan",
+                            "linux1804-64",
+                            "linux1804-64-asan",
+                        ],
+                    },
+                ]
+            ),
+        )
+
+    def test_u_platforms_negated(self):
+        "-u gtest[-linux] selects all platforms but linux for gtest"
+        parameters = parse_message("try: -u gtest[-linux]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        all_platforms = {x.attributes["test_platform"] for x in unittest_tasks.values()}
+        self.assertEqual(
+            sorted(tos.unittests[0]["platforms"]),
+            sorted(x for x in all_platforms if x != "linux"),
+        )
+
+    def test_u_platforms_negated_pretty(self):
+        "-u gtest[Ubuntu,-x64] selects just linux for gtest"
+        parameters = parse_message("try: -u gtest[Ubuntu,-x64]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            sorted(tos.unittests),
+            sorted(
+                [
+                    {"test": "gtest", "platforms": ["linux32"]},
+                ]
+            ),
+        )
+
+    def test_u_chunks_platforms(self):
+        "-u gtest-1[linux,win32] selects the linux and win32 platforms for chunk 1 of gtest"
+        parameters = parse_message("try: -u gtest-1[linux,win32]")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(
+            tos.unittests,
+            [
+                {
+                    "test": "gtest",
+                    "platforms": ["linux", "win32"],
+                    "only_chunks": set("1"),
+                },
+            ],
+        )
+
+    def test_t_none(self):
+        "-t none sets talos=[]"
+        parameters = parse_message("try: -t none")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.talos, [])
+
+    def test_t_all(self):
+        "-t all sets talos=[..whole list..]"
+        parameters = parse_message("try: -t all")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.talos, [{"test": t} for t in sorted(talos_tasks)])
+
+    def test_t_single(self):
+        "-t mochitest-webgl sets talos=[mochitest-webgl]"
+        parameters = parse_message("try: -t mochitest-webgl")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.talos, [{"test": "mochitest-webgl"}])
+
+    # -t shares an implementation with -u, so it's not tested heavily
+
+    def test_trigger_tests(self):
+        "--rebuild 10 sets trigger_tests"
+        parameters = parse_message("try: --rebuild 10")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.trigger_tests, 10)
+
+    def test_talos_trigger_tests(self):
+        "--rebuild-talos 10 sets talos_trigger_tests"
+        parameters = parse_message("try: --rebuild-talos 10")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.talos_trigger_tests, 10)
+
+    def test_interactive(self):
+        "--interactive sets interactive"
+        parameters = parse_message("try: --interactive")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.interactive, True)
+
+    def test_all_email(self):
+        "--all-emails sets notifications"
+        parameters = parse_message("try: --all-emails")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.notifications, "all")
+
+    def test_fail_email(self):
+        "--failure-emails sets notifications"
+        parameters = parse_message("try: --failure-emails")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.notifications, "failure")
+
+    def test_no_email(self):
+        "no email settings don't set notifications"
+        parameters = parse_message("try:")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.notifications, None)
+
+    def test_setenv(self):
+        "--setenv VAR=value adds a environment variables setting to env"
+        parameters = parse_message("try: --setenv VAR1=value1 --setenv VAR2=value2")
+        assert parameters["try_task_config"]["env"] == {
+            "VAR1": "value1",
+            "VAR2": "value2",
+        }
+
+    def test_profile(self):
+        "--gecko-profile sets profile to true"
+        parameters = parse_message("try: --gecko-profile")
+        assert parameters["try_task_config"]["gecko-profile"] is True
+
+    def test_tag(self):
+        "--tag TAG sets tag to TAG value"
+        parameters = parse_message("try: --tag tagName")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertEqual(tos.tag, "tagName")
+
+    def test_no_retry(self):
+        "--no-retry sets no_retry to true"
+        parameters = parse_message("try: --no-retry")
+        tos = TryOptionSyntax(parameters, graph_with_jobs, GRAPH_CONFIG)
+        self.assertTrue(tos.no_retry)
+
+    def test_artifact(self):
+        "--artifact sets artifact to true"
+        parameters = parse_message("try: --artifact")
+        assert parameters["try_task_config"]["use-artifact-builds"] is True
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_attributes.py b/taskcluster/gecko_taskgraph/test/test_util_attributes.py
new file mode 100644
index 0000000000..26181cb8bf
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_attributes.py
@@ -0,0 +1,99 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import unittest
+
+from mozunit import main
+from taskgraph.util.attributes import attrmatch
+
+from gecko_taskgraph.util.attributes import match_run_on_projects
+
+
+class Attrmatch(unittest.TestCase):
+    def test_trivial_match(self):
+        """Given no conditions, anything matches"""
+        self.assertTrue(attrmatch({}))
+
+    def test_missing_attribute(self):
+        """If a filtering attribute is not present, no match"""
+        self.assertFalse(attrmatch({}, someattr=10))
+
+    def test_literal_attribute(self):
+        """Literal attributes must match exactly"""
+        self.assertTrue(attrmatch({"att": 10}, att=10))
+        self.assertFalse(attrmatch({"att": 10}, att=20))
+
+    def test_set_attribute(self):
+        """Set attributes require set membership"""
+        self.assertTrue(attrmatch({"att": 10}, att={9, 10}))
+        self.assertFalse(attrmatch({"att": 10}, att={19, 20}))
+
+    def test_callable_attribute(self):
+        """Callable attributes are called and any False causes the match to fail"""
+        self.assertTrue(attrmatch({"att": 10}, att=lambda val: True))
+        self.assertFalse(attrmatch({"att": 10}, att=lambda val: False))
+
+        def even(val):
+            return val % 2 == 0
+
+        self.assertTrue(attrmatch({"att": 10}, att=even))
+        self.assertFalse(attrmatch({"att": 11}, att=even))
+
+    def test_all_matches_required(self):
+        """If only one attribute does not match, the result is False"""
+        self.assertFalse(attrmatch({"a": 1}, a=1, b=2, c=3))
+        self.assertFalse(attrmatch({"a": 1, "b": 2}, a=1, b=2, c=3))
+        self.assertTrue(attrmatch({"a": 1, "b": 2, "c": 3}, a=1, b=2, c=3))
+
+
+class MatchRunOnProjects(unittest.TestCase):
+    def test_empty(self):
+        self.assertFalse(match_run_on_projects("birch", []))
+
+    def test_all(self):
+        self.assertTrue(match_run_on_projects("birch", ["all"]))
+        self.assertTrue(match_run_on_projects("larch", ["all"]))
+        self.assertTrue(match_run_on_projects("autoland", ["all"]))
+        self.assertTrue(match_run_on_projects("mozilla-central", ["all"]))
+        self.assertTrue(match_run_on_projects("mozilla-beta", ["all"]))
+        self.assertTrue(match_run_on_projects("mozilla-release", ["all"]))
+
+    def test_release(self):
+        self.assertFalse(match_run_on_projects("birch", ["release"]))
+        self.assertFalse(match_run_on_projects("larch", ["release"]))
+        self.assertFalse(match_run_on_projects("autoland", ["release"]))
+        self.assertTrue(match_run_on_projects("mozilla-central", ["release"]))
+        self.assertTrue(match_run_on_projects("mozilla-beta", ["release"]))
+        self.assertTrue(match_run_on_projects("mozilla-release", ["release"]))
+
+    def test_integration(self):
+        self.assertFalse(match_run_on_projects("birch", ["integration"]))
+        self.assertFalse(match_run_on_projects("larch", ["integration"]))
+        self.assertTrue(match_run_on_projects("autoland", ["integration"]))
+        self.assertFalse(match_run_on_projects("mozilla-central", ["integration"]))
+        self.assertFalse(match_run_on_projects("mozilla-beta", ["integration"]))
+        self.assertFalse(match_run_on_projects("mozilla-integration", ["integration"]))
+
+    def test_combo(self):
+        self.assertTrue(match_run_on_projects("birch", ["release", "birch", "maple"]))
+        self.assertFalse(match_run_on_projects("larch", ["release", "birch", "maple"]))
+        self.assertTrue(match_run_on_projects("maple", ["release", "birch", "maple"]))
+        self.assertFalse(
+            match_run_on_projects("autoland", ["release", "birch", "maple"])
+        )
+        self.assertTrue(
+            match_run_on_projects("mozilla-central", ["release", "birch", "maple"])
+        )
+        self.assertTrue(
+            match_run_on_projects("mozilla-beta", ["release", "birch", "maple"])
+        )
+        self.assertTrue(
+            match_run_on_projects("mozilla-release", ["release", "birch", "maple"])
+        )
+        self.assertTrue(match_run_on_projects("birch", ["birch", "trunk"]))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_backstop.py b/taskcluster/gecko_taskgraph/test/test_util_backstop.py
new file mode 100644
index 0000000000..af9aabd5af
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_backstop.py
@@ -0,0 +1,155 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from datetime import datetime
+from textwrap import dedent
+from time import mktime
+
+import pytest
+from mozunit import main
+from taskgraph.util.taskcluster import get_artifact_url, get_index_url, get_task_url
+
+from gecko_taskgraph.util.backstop import (
+    BACKSTOP_INDEX,
+    BACKSTOP_PUSH_INTERVAL,
+    BACKSTOP_TIME_INTERVAL,
+    is_backstop,
+)
+
+LAST_BACKSTOP_ID = 0
+LAST_BACKSTOP_PUSHDATE = mktime(datetime.now().timetuple())
+DEFAULT_RESPONSES = {
+    "index": {
+        "status": 200,
+        "json": {"taskId": LAST_BACKSTOP_ID},
+    },
+    "artifact": {
+        "status": 200,
+        "body": dedent(
+            """
+            pushdate: {}
+        """.format(
+                LAST_BACKSTOP_PUSHDATE
+            )
+        ),
+    },
+    "status": {
+        "status": 200,
+        "json": {"status": {"state": "complete"}},
+    },
+}
+
+
+@pytest.fixture
+def params():
+    return {
+        "branch": "integration/autoland",
+        "head_repository": "https://hg.mozilla.org/integration/autoland",
+        "head_rev": "abcdef",
+        "project": "autoland",
+        "pushdate": LAST_BACKSTOP_PUSHDATE + 1,
+        "pushlog_id": LAST_BACKSTOP_ID + 1,
+    }
+
+
+@pytest.mark.parametrize(
+    "response_args,extra_params,expected",
+    (
+        pytest.param(
+            {
+                "index": {"status": 404},
+            },
+            {"pushlog_id": 1},
+            True,
+            id="no previous backstop",
+        ),
+        pytest.param(
+            {
+                "index": DEFAULT_RESPONSES["index"],
+                "status": DEFAULT_RESPONSES["status"],
+                "artifact": {"status": 404},
+            },
+            {"pushlog_id": 1},
+            False,
+            id="previous backstop not finished",
+        ),
+        pytest.param(
+            DEFAULT_RESPONSES,
+            {
+                "pushlog_id": LAST_BACKSTOP_ID + 1,
+                "pushdate": LAST_BACKSTOP_PUSHDATE + 1,
+            },
+            False,
+            id="not a backstop",
+        ),
+        pytest.param(
+            {},
+            {
+                "pushlog_id": BACKSTOP_PUSH_INTERVAL,
+            },
+            True,
+            id="backstop interval",
+        ),
+        pytest.param(
+            DEFAULT_RESPONSES,
+            {
+                "pushdate": LAST_BACKSTOP_PUSHDATE + (BACKSTOP_TIME_INTERVAL * 60),
+            },
+            True,
+            id="time elapsed",
+        ),
+        pytest.param(
+            {},
+            {
+                "project": "try",
+                "pushlog_id": BACKSTOP_PUSH_INTERVAL,
+            },
+            False,
+            id="try not a backstop",
+        ),
+        pytest.param(
+            {},
+            {
+                "project": "mozilla-central",
+            },
+            True,
+            id="release branches always a backstop",
+        ),
+        pytest.param(
+            {
+                "index": DEFAULT_RESPONSES["index"],
+                "status": {
+                    "status": 200,
+                    "json": {"status": {"state": "failed"}},
+                },
+            },
+            {},
+            True,
+            id="last backstop failed",
+        ),
+    ),
+)
+def test_is_backstop(responses, params, response_args, extra_params, expected):
+    urls = {
+        "index": get_index_url(
+            BACKSTOP_INDEX.format(
+                **{"trust-domain": "gecko", "project": params["project"]}
+            )
+        ),
+        "artifact": get_artifact_url(LAST_BACKSTOP_ID, "public/parameters.yml"),
+        "status": get_task_url(LAST_BACKSTOP_ID) + "/status",
+    }
+
+    for key in ("index", "status", "artifact"):
+        if key in response_args:
+            print(urls[key])
+            responses.add(responses.GET, urls[key], **response_args[key])
+
+    params.update(extra_params)
+    assert is_backstop(params) is expected
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_bugbug.py b/taskcluster/gecko_taskgraph/test/test_util_bugbug.py
new file mode 100644
index 0000000000..7e8865ddde
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_bugbug.py
@@ -0,0 +1,57 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import mozunit
+
+from gecko_taskgraph.util.bugbug import BUGBUG_BASE_URL, push_schedules
+
+
+def test_group_translation(responses):
+    branch = ("integration/autoland",)
+    rev = "abcdef"
+    query = f"/push/{branch}/{rev}/schedules"
+    url = BUGBUG_BASE_URL + query
+
+    responses.add(
+        responses.GET,
+        url,
+        json={
+            "groups": {
+                "dom/indexedDB": 1,
+                "testing/web-platform/tests/IndexedDB": 1,
+                "testing/web-platform/mozilla/tests/IndexedDB": 1,
+            },
+            "config_groups": {
+                "dom/indexedDB": ["label1", "label2"],
+                "testing/web-platform/tests/IndexedDB": ["label3"],
+                "testing/web-platform/mozilla/tests/IndexedDB": ["label4"],
+            },
+        },
+        status=200,
+    )
+
+    assert len(push_schedules) == 0
+    data = push_schedules(branch, rev)
+    print(data)
+    assert sorted(data["groups"]) == [
+        "/IndexedDB",
+        "/_mozilla/IndexedDB",
+        "dom/indexedDB",
+    ]
+    assert data["config_groups"] == {
+        "dom/indexedDB": ["label1", "label2"],
+        "/IndexedDB": ["label3"],
+        "/_mozilla/IndexedDB": ["label4"],
+    }
+    assert len(push_schedules) == 1
+
+    # Value is memoized.
+    responses.reset()
+    push_schedules(branch, rev)
+    assert len(push_schedules) == 1
+
+
+if __name__ == "__main__":
+    mozunit.main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_chunking.py b/taskcluster/gecko_taskgraph/test/test_util_chunking.py
new file mode 100644
index 0000000000..99434af042
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_chunking.py
@@ -0,0 +1,403 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import re
+from itertools import combinations
+
+import pytest
+from mozunit import main
+
+from gecko_taskgraph.util import chunking
+
+pytestmark = pytest.mark.slow
+
+
+@pytest.fixture(scope="module")
+def mock_manifest_runtimes():
+    """Deterministically produce a list of simulated manifest runtimes.
+
+    Args:
+        manifests (list): list of manifests against which simulated manifest
+            runtimes would be paired up to.
+
+    Returns:
+        dict of manifest data paired with a float value representing runtime.
+    """
+
+    def inner(manifests):
+        manifests = sorted(manifests)
+        # Generate deterministic runtime data.
+        runtimes = [(i / 10) ** (i / 10) for i in range(len(manifests))]
+        return dict(zip(manifests, runtimes))
+
+    return inner
+
+
+@pytest.fixture(scope="module")
+def unchunked_manifests():
+    """Produce a list of unchunked manifests to be consumed by test method.
+
+    Args:
+        length (int, optional): number of path elements to keep.
+        cutoff (int, optional): number of generated test paths to remove
+            from the test set if user wants to limit the number of paths.
+
+    Returns:
+        list: list of test paths.
+    """
+    data = ["blueberry", "nashi", "peach", "watermelon"]
+
+    def inner(suite, length=2, cutoff=0):
+        if "web-platform" in suite:
+            suffix = ""
+            prefix = "/"
+        elif "reftest" in suite:
+            suffix = ".list"
+            prefix = ""
+        else:
+            suffix = ".ini"
+            prefix = ""
+        return [prefix + "/".join(p) + suffix for p in combinations(data, length)][
+            cutoff:
+        ]
+
+    return inner
+
+
+@pytest.fixture(scope="module")
+def mock_task_definition():
+    """Builds a mock task definition for use in testing.
+
+    Args:
+        os_name (str): represents the os.
+        os_version (str): represents the os version
+        bits (int): software bits.
+        build_type (str): opt or debug.
+        build_attrs (list, optional): specify build attribute(s)
+        variants (list, optional): specify runtime variant(s)
+
+    Returns:
+        dict: mocked task definition.
+    """
+
+    def inner(os_name, os_version, bits, build_type, build_attrs=None, variants=None):
+        setting = {
+            "platform": {
+                "arch": str(bits),
+                "os": {
+                    "name": os_name,
+                    "version": os_version,
+                },
+            },
+            "build": {
+                "type": build_type,
+            },
+            "runtime": {},
+        }
+
+        # Optionally set build attributes and runtime variants.
+        if build_attrs:
+            if isinstance(build_attrs, str):
+                build_attrs = [build_attrs]
+            for attr in build_attrs:
+                setting["build"][attr] = True
+
+        if variants:
+            if isinstance(variants, str):
+                variants = [variants]
+            for variant in variants:
+                setting["runtime"][variant] = True
+        return {"test-name": "foo", "test-setting": setting}
+
+    return inner
+
+
+@pytest.fixture(scope="module")
+def mock_mozinfo():
+    """Returns a mocked mozinfo object, similar to guess_mozinfo_from_task().
+
+    Args:
+        os (str): typically one of 'win, linux, mac, android'.
+        processor (str): processor architecture.
+        asan (bool, optional): addressanitizer build.
+        bits (int, optional): defaults to 64.
+        ccov (bool, optional): code coverage build.
+        debug (bool, optional): debug type build.
+        fission (bool, optional): process fission.
+        headless (bool, optional): headless browser testing without displays.
+        tsan (bool, optional): threadsanitizer build.
+
+    Returns:
+        dict: Dictionary mimickign the results from guess_mozinfo_from_task.
+    """
+
+    def inner(
+        os,
+        processor,
+        asan=False,
+        bits=64,
+        ccov=False,
+        debug=False,
+        fission=False,
+        headless=False,
+        tsan=False,
+    ):
+        return {
+            "os": os,
+            "processor": processor,
+            "toolkit": "",
+            "asan": asan,
+            "bits": bits,
+            "ccov": ccov,
+            "debug": debug,
+            "e10s": True,
+            "fission": fission,
+            "headless": headless,
+            "tsan": tsan,
+            "appname": "firefox",
+            "condprof": False,
+        }
+
+    return inner
+
+
+@pytest.mark.parametrize(
+    "params,exception",
+    [
+        [("win", "7", 32, "opt"), None],
+        [("win", "10", 64, "opt"), None],
+        [("linux", "1804", 64, "debug"), None],
+        [("macosx", "1015", 64, "debug"), None],
+        [("macosx", "1100", 64, "opt"), None],
+        [("android", "", 64, "debug"), None],
+        [("and", "", 64, "debug"), ValueError],
+        [("", "", 64, "opt"), ValueError],
+        [("linux", "1804", 64, "opt", ["ccov"]), None],
+        [("linux", "1804", 64, "opt", ["asan"]), None],
+        [("win", "10", 64, "opt", ["tsan"]), None],
+        [("mac", "1100", 64, "opt", ["ccov"]), None],
+        [("android", "", 64, "opt", None, ["fission"]), None],
+        [("win", "10", "aarch64", "opt"), None],
+    ],
+)
+def test_guess_mozinfo_from_task(params, exception, mock_task_definition):
+    """Tests the mozinfo guessing process."""
+    # Set up a mocked task object.
+    task = mock_task_definition(*params)
+
+    if exception:
+        with pytest.raises(exception):
+            result = chunking.guess_mozinfo_from_task(task)
+    else:
+        expected_toolkits = {
+            "android": "android",
+            "linux": "gtk",
+            "mac": "cocoa",
+            "win": "windows",
+        }
+        result = chunking.guess_mozinfo_from_task(task)
+        setting = task["test-setting"]
+
+        assert str(result["bits"]) in setting["platform"]["arch"]
+        assert result["os"] in ("android", "linux", "mac", "win")
+        assert result["os"] in setting["platform"]["os"]["name"]
+        assert result["toolkit"] == expected_toolkits[result["os"]]
+
+        # Ensure the outcome of special build variants being present match what
+        # guess_mozinfo_from_task method returns for these attributes.
+        assert ("asan" in setting["build"]) == result["asan"]
+        assert ("tsan" in setting["build"]) == result["tsan"]
+        assert ("ccov" in setting["build"]) == result["ccov"]
+
+        # Ensure runtime variants match
+        assert ("fission" in setting["runtime"]) == result["fission"]
+        assert ("1proc" in setting["runtime"]) != result["e10s"]
+
+
+@pytest.mark.parametrize("platform", ["unix", "windows", "android"])
+@pytest.mark.parametrize(
+    "suite", ["crashtest", "reftest", "web-platform-tests", "xpcshell"]
+)
+def test_get_runtimes(platform, suite):
+    """Tests that runtime information is returned for known good configurations."""
+    assert chunking.get_runtimes(platform, suite)
+
+
+@pytest.mark.parametrize(
+    "platform,suite,exception",
+    [
+        ("nonexistent_platform", "nonexistent_suite", KeyError),
+        ("unix", "nonexistent_suite", KeyError),
+        ("unix", "", TypeError),
+        ("", "", TypeError),
+        ("", "nonexistent_suite", TypeError),
+    ],
+)
+def test_get_runtimes_invalid(platform, suite, exception):
+    """Ensure get_runtimes() method raises an exception if improper request is made."""
+    with pytest.raises(exception):
+        chunking.get_runtimes(platform, suite)
+
+
+@pytest.mark.parametrize(
+    "suite",
+    [
+        "web-platform-tests",
+        "web-platform-tests-reftest",
+        "web-platform-tests-wdspec",
+        "web-platform-tests-crashtest",
+    ],
+)
+@pytest.mark.parametrize("chunks", [1, 3, 6, 20])
+def test_mock_chunk_manifests_wpt(unchunked_manifests, suite, chunks):
+    """Tests web-platform-tests and its subsuites chunking process."""
+    # Setup.
+    manifests = unchunked_manifests(suite)
+
+    # Generate the expected results, by generating list of indices that each
+    # manifest should go into and then appending each item to that index.
+    # This method is intentionally different from the way chunking.py performs
+    # chunking for cross-checking.
+    expected = [[] for _ in range(chunks)]
+    indexed = zip(manifests, list(range(0, chunks)) * len(manifests))
+    for i in indexed:
+        expected[i[1]].append(i[0])
+
+    # Call the method under test on unchunked manifests.
+    chunked_manifests = chunking.chunk_manifests(suite, "unix", chunks, manifests)
+
+    # Assertions and end test.
+    assert chunked_manifests
+    if chunks > len(manifests):
+        # If chunk count exceeds number of manifests, not all chunks will have
+        # manifests.
+        with pytest.raises(AssertionError):
+            assert all(chunked_manifests)
+    else:
+        assert all(chunked_manifests)
+        minimum = min(len(c) for c in chunked_manifests)
+        maximum = max(len(c) for c in chunked_manifests)
+        assert maximum - minimum <= 1
+        assert expected == chunked_manifests
+
+
+@pytest.mark.parametrize(
+    "suite",
+    [
+        "mochitest-devtools-chrome",
+        "mochitest-browser-chrome",
+        "mochitest-plain",
+        "mochitest-chrome",
+        "xpcshell",
+    ],
+)
+@pytest.mark.parametrize("chunks", [1, 3, 6, 20])
+def test_mock_chunk_manifests(
+    mock_manifest_runtimes, unchunked_manifests, suite, chunks
+):
+    """Tests non-WPT tests and its subsuites chunking process."""
+    # Setup.
+    manifests = unchunked_manifests(suite)
+
+    # Call the method under test on unchunked manifests.
+    chunked_manifests = chunking.chunk_manifests(suite, "unix", chunks, manifests)
+
+    # Assertions and end test.
+    assert chunked_manifests
+    if chunks > len(manifests):
+        # If chunk count exceeds number of manifests, not all chunks will have
+        # manifests.
+        with pytest.raises(AssertionError):
+            assert all(chunked_manifests)
+    else:
+        assert all(chunked_manifests)
+
+
+@pytest.mark.parametrize(
+    "suite",
+    [
+        "web-platform-tests",
+        "web-platform-tests-reftest",
+        "xpcshell",
+        "mochitest-plain",
+        "mochitest-devtools-chrome",
+        "mochitest-browser-chrome",
+        "mochitest-chrome",
+    ],
+)
+@pytest.mark.parametrize(
+    "platform",
+    [
+        ("mac", "x86_64"),
+        ("win", "x86_64"),
+        ("win", "x86"),
+        ("win", "aarch64"),
+        ("linux", "x86_64"),
+        ("linux", "x86"),
+    ],
+)
+def test_get_manifests(suite, platform, mock_mozinfo):
+    """Tests the DefaultLoader class' ability to load manifests."""
+    mozinfo = mock_mozinfo(*platform)
+
+    loader = chunking.DefaultLoader([])
+    manifests = loader.get_manifests(suite, frozenset(mozinfo.items()))
+
+    assert manifests
+    assert manifests["active"]
+    if "web-platform" in suite:
+        assert manifests["skipped"] == []
+    else:
+        assert manifests["skipped"]
+
+    items = manifests["active"]
+    if suite == "xpcshell":
+        assert all([re.search(r"xpcshell(.*)?.ini", m) for m in items])
+    if "mochitest" in suite:
+        assert all([re.search(r"(mochitest|chrome|browser).*.ini", m) for m in items])
+    if "web-platform" in suite:
+        assert all([m.startswith("/") and m.count("/") <= 4 for m in items])
+
+
+@pytest.mark.parametrize(
+    "suite",
+    [
+        "mochitest-devtools-chrome",
+        "mochitest-browser-chrome",
+        "mochitest-plain",
+        "mochitest-chrome",
+        "web-platform-tests",
+        "web-platform-tests-reftest",
+        "xpcshell",
+    ],
+)
+@pytest.mark.parametrize(
+    "platform",
+    [
+        ("mac", "x86_64"),
+        ("win", "x86_64"),
+        ("linux", "x86_64"),
+    ],
+)
+@pytest.mark.parametrize("chunks", [1, 3, 6, 20])
+def test_chunk_manifests(suite, platform, chunks, mock_mozinfo):
+    """Tests chunking with real manifests."""
+    mozinfo = mock_mozinfo(*platform)
+
+    loader = chunking.DefaultLoader([])
+    manifests = loader.get_manifests(suite, frozenset(mozinfo.items()))
+
+    chunked_manifests = chunking.chunk_manifests(
+        suite, platform, chunks, manifests["active"]
+    )
+
+    # Assertions and end test.
+    assert chunked_manifests
+    assert len(chunked_manifests) == chunks
+    assert all(chunked_manifests)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_docker.py b/taskcluster/gecko_taskgraph/test/test_util_docker.py
new file mode 100644
index 0000000000..49c01738fe
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_docker.py
@@ -0,0 +1,255 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import os
+import shutil
+import stat
+import tarfile
+import tempfile
+import unittest
+from unittest import mock
+
+import taskcluster_urls as liburls
+from mozunit import MockedOpen, main
+
+from gecko_taskgraph.util import docker
+
+MODE_STANDARD = stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IROTH
+
+
+@mock.patch.dict("os.environ", {"TASKCLUSTER_ROOT_URL": liburls.test_root_url()})
+class TestDocker(unittest.TestCase):
+    def test_generate_context_hash(self):
+        tmpdir = tempfile.mkdtemp()
+        try:
+            os.makedirs(os.path.join(tmpdir, "docker", "my-image"))
+            p = os.path.join(tmpdir, "docker", "my-image", "Dockerfile")
+            with open(p, "w") as f:
+                f.write("FROM node\nADD a-file\n")
+            os.chmod(p, MODE_STANDARD)
+            p = os.path.join(tmpdir, "docker", "my-image", "a-file")
+            with open(p, "w") as f:
+                f.write("data\n")
+            os.chmod(p, MODE_STANDARD)
+            self.assertIn(
+                docker.generate_context_hash(
+                    tmpdir,
+                    os.path.join(tmpdir, "docker/my-image"),
+                    "my-image",
+                    {},
+                ),
+                (
+                    "680532a33c845e3b4f8ea8a7bd697da579b647f28c29f7a0a71e51e6cca33983",
+                    "cc02f943ae87b283749369fa9c4f6a74639c27a7b9972c99de58e5d9fb3a98ae",
+                ),
+            )
+        finally:
+            shutil.rmtree(tmpdir)
+
+    def test_docker_image_explicit_registry(self):
+        files = {}
+        files[f"{docker.IMAGE_DIR}/myimage/REGISTRY"] = "cool-images"
+        files[f"{docker.IMAGE_DIR}/myimage/VERSION"] = "1.2.3"
+        files[f"{docker.IMAGE_DIR}/myimage/HASH"] = "sha256:434..."
+        with MockedOpen(files):
+            self.assertEqual(
+                docker.docker_image("myimage"), "cool-images/myimage@sha256:434..."
+            )
+
+    def test_docker_image_explicit_registry_by_tag(self):
+        files = {}
+        files[f"{docker.IMAGE_DIR}/myimage/REGISTRY"] = "myreg"
+        files[f"{docker.IMAGE_DIR}/myimage/VERSION"] = "1.2.3"
+        files[f"{docker.IMAGE_DIR}/myimage/HASH"] = "sha256:434..."
+        with MockedOpen(files):
+            self.assertEqual(
+                docker.docker_image("myimage", by_tag=True), "myreg/myimage:1.2.3"
+            )
+
+    def test_docker_image_default_registry(self):
+        files = {}
+        files[f"{docker.IMAGE_DIR}/REGISTRY"] = "mozilla"
+        files[f"{docker.IMAGE_DIR}/myimage/VERSION"] = "1.2.3"
+        files[f"{docker.IMAGE_DIR}/myimage/HASH"] = "sha256:434..."
+        with MockedOpen(files):
+            self.assertEqual(
+                docker.docker_image("myimage"), "mozilla/myimage@sha256:434..."
+            )
+
+    def test_docker_image_default_registry_by_tag(self):
+        files = {}
+        files[f"{docker.IMAGE_DIR}/REGISTRY"] = "mozilla"
+        files[f"{docker.IMAGE_DIR}/myimage/VERSION"] = "1.2.3"
+        files[f"{docker.IMAGE_DIR}/myimage/HASH"] = "sha256:434..."
+        with MockedOpen(files):
+            self.assertEqual(
+                docker.docker_image("myimage", by_tag=True), "mozilla/myimage:1.2.3"
+            )
+
+    def test_create_context_tar_basic(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test_image")
+            os.mkdir(d)
+            with open(os.path.join(d, "Dockerfile"), "a"):
+                pass
+            os.chmod(os.path.join(d, "Dockerfile"), MODE_STANDARD)
+
+            with open(os.path.join(d, "extra"), "a"):
+                pass
+            os.chmod(os.path.join(d, "extra"), MODE_STANDARD)
+
+            tp = os.path.join(tmp, "tar")
+            h = docker.create_context_tar(tmp, d, tp, "my_image", {})
+            self.assertIn(
+                h,
+                (
+                    "eae3ad00936085eb3e5958912f79fb06ee8e14a91f7157c5f38625f7ddacb9c7",
+                    "9ff54ee091c4f346e94e809b03efae5aa49a5c1db152f9f633682cfa005f7422",
+                ),
+            )
+
+            # File prefix should be "my_image"
+            with tarfile.open(tp, "r:gz") as tf:
+                self.assertEqual(
+                    tf.getnames(),
+                    [
+                        "Dockerfile",
+                        "extra",
+                    ],
+                )
+        finally:
+            shutil.rmtree(tmp)
+
+    def test_create_context_topsrcdir_files(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test-image")
+            os.mkdir(d)
+            with open(os.path.join(d, "Dockerfile"), "wb") as fh:
+                fh.write(b"# %include extra/file0\n")
+            os.chmod(os.path.join(d, "Dockerfile"), MODE_STANDARD)
+
+            extra = os.path.join(tmp, "extra")
+            os.mkdir(extra)
+            with open(os.path.join(extra, "file0"), "a"):
+                pass
+            os.chmod(os.path.join(extra, "file0"), MODE_STANDARD)
+
+            tp = os.path.join(tmp, "tar")
+            h = docker.create_context_tar(tmp, d, tp, "test_image", {})
+            self.assertIn(
+                h,
+                (
+                    "49dc3827530cd344d7bcc52e1fdd4aefc632568cf442cffd3dd9633a58f271bf",
+                    "8f8e3dd2b712003cd12bb39e5a84fc2a7c06e891cf481613a52bf3db472c4ca9",
+                ),
+            )
+
+            with tarfile.open(tp, "r:gz") as tf:
+                self.assertEqual(
+                    tf.getnames(),
+                    [
+                        "Dockerfile",
+                        "topsrcdir/extra/file0",
+                    ],
+                )
+        finally:
+            shutil.rmtree(tmp)
+
+    def test_create_context_absolute_path(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test-image")
+            os.mkdir(d)
+
+            # Absolute paths in %include syntax are not allowed.
+            with open(os.path.join(d, "Dockerfile"), "wb") as fh:
+                fh.write(b"# %include /etc/shadow\n")
+
+            with self.assertRaisesRegexp(Exception, "cannot be absolute"):
+                docker.create_context_tar(tmp, d, os.path.join(tmp, "tar"), "test", {})
+        finally:
+            shutil.rmtree(tmp)
+
+    def test_create_context_outside_topsrcdir(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test-image")
+            os.mkdir(d)
+
+            with open(os.path.join(d, "Dockerfile"), "wb") as fh:
+                fh.write(b"# %include foo/../../../etc/shadow\n")
+
+            with self.assertRaisesRegexp(Exception, "path outside topsrcdir"):
+                docker.create_context_tar(tmp, d, os.path.join(tmp, "tar"), "test", {})
+        finally:
+            shutil.rmtree(tmp)
+
+    def test_create_context_missing_extra(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test-image")
+            os.mkdir(d)
+
+            with open(os.path.join(d, "Dockerfile"), "wb") as fh:
+                fh.write(b"# %include does/not/exist\n")
+
+            with self.assertRaisesRegexp(Exception, "path does not exist"):
+                docker.create_context_tar(tmp, d, os.path.join(tmp, "tar"), "test", {})
+        finally:
+            shutil.rmtree(tmp)
+
+    def test_create_context_extra_directory(self):
+        tmp = tempfile.mkdtemp()
+        try:
+            d = os.path.join(tmp, "test-image")
+            os.mkdir(d)
+
+            with open(os.path.join(d, "Dockerfile"), "wb") as fh:
+                fh.write(b"# %include extra\n")
+                fh.write(b"# %include file0\n")
+            os.chmod(os.path.join(d, "Dockerfile"), MODE_STANDARD)
+
+            extra = os.path.join(tmp, "extra")
+            os.mkdir(extra)
+            for i in range(3):
+                p = os.path.join(extra, "file%d" % i)
+                with open(p, "wb") as fh:
+                    fh.write(b"file%d" % i)
+                os.chmod(p, MODE_STANDARD)
+
+            with open(os.path.join(tmp, "file0"), "a"):
+                pass
+            os.chmod(os.path.join(tmp, "file0"), MODE_STANDARD)
+
+            tp = os.path.join(tmp, "tar")
+            h = docker.create_context_tar(tmp, d, tp, "my_image", {})
+
+            self.assertIn(
+                h,
+                (
+                    "a392f23cd6606ae43116390a4d0113354cff1e688a41d46f48b0fb25e90baa13",
+                    "02325bdc508c2e941959170beeb840f6bb91d0675cb8095783a7db7301d136b2",
+                ),
+            )
+
+            with tarfile.open(tp, "r:gz") as tf:
+                self.assertEqual(
+                    tf.getnames(),
+                    [
+                        "Dockerfile",
+                        "topsrcdir/extra/file0",
+                        "topsrcdir/extra/file1",
+                        "topsrcdir/extra/file2",
+                        "topsrcdir/file0",
+                    ],
+                )
+        finally:
+            shutil.rmtree(tmp)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_partials.py b/taskcluster/gecko_taskgraph/test/test_util_partials.py
new file mode 100644
index 0000000000..3630d7b0ec
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_partials.py
@@ -0,0 +1,128 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import unittest
+from unittest import mock
+
+from mozunit import main
+
+from gecko_taskgraph.util import partials
+
+release_blob = {
+    "fileUrls": {
+        "release-localtest": {
+            "completes": {
+                "*": "%OS_FTP%/%LOCALE%/firefox-92.0.1.complete.mar",
+            }
+        }
+    },
+    "platforms": {
+        "WINNT_x86_64-msvc": {
+            "locales": {
+                "en-US": {
+                    "buildID": "20210922161155",
+                }
+            }
+        }
+    },
+}
+
+
+def nightly_blob(release):
+    return {
+        "platforms": {
+            "WINNT_x86_64-msvc": {
+                "locales": {
+                    "en-US": {
+                        "buildID": release[-14:],
+                        "completes": [{"fileUrl": release}],
+                    }
+                }
+            }
+        }
+    }
+
+
+class TestReleaseHistory(unittest.TestCase):
+    @mock.patch("gecko_taskgraph.util.partials.get_release_builds")
+    @mock.patch("gecko_taskgraph.util.partials.get_sorted_releases")
+    def test_populate_release_history(self, get_sorted_releases, get_release_builds):
+        self.assertEqual(
+            partials.populate_release_history(
+                "Firefox", "mozilla-release", partial_updates={}
+            ),
+            {},
+        )
+        get_sorted_releases.assert_not_called()
+        get_release_builds.assert_not_called()
+
+        def patched_get_sorted_releases(product, branch):
+            assert branch == "mozilla-central"
+            return [
+                "Firefox-mozilla-central-nightly-20211003201113",
+                "Firefox-mozilla-central-nightly-20211003100640",
+                "Firefox-mozilla-central-nightly-20211002213629",
+                "Firefox-mozilla-central-nightly-20211002095048",
+                "Firefox-mozilla-central-nightly-20211001214601",
+                "Firefox-mozilla-central-nightly-20211001093323",
+            ]
+
+        def patched_get_release_builds(release, branch):
+            if branch == "mozilla-central":
+                return nightly_blob(release)
+            if branch == "mozilla-release":
+                return release_blob
+
+        get_sorted_releases.side_effect = patched_get_sorted_releases
+        get_release_builds.side_effect = patched_get_release_builds
+
+        self.assertEqual(
+            partials.populate_release_history(
+                "Firefox",
+                "mozilla-release",
+                partial_updates={"92.0.1": {"buildNumber": 1}},
+            ),
+            {
+                "WINNT_x86_64-msvc": {
+                    "en-US": {
+                        "target-92.0.1.partial.mar": {
+                            "buildid": "20210922161155",
+                            "mar_url": "win64/en-US/firefox-92.0.1.complete.mar",
+                            "previousVersion": "92.0.1",
+                            "previousBuildNumber": 1,
+                            "product": "Firefox",
+                        }
+                    }
+                }
+            },
+        )
+        self.assertEqual(
+            partials.populate_release_history("Firefox", "mozilla-central"),
+            {
+                "WINNT_x86_64-msvc": {
+                    "en-US": {
+                        "target.partial-1.mar": {
+                            "buildid": "20211003201113",
+                            "mar_url": "Firefox-mozilla-central-nightly-20211003201113",
+                        },
+                        "target.partial-2.mar": {
+                            "buildid": "20211003100640",
+                            "mar_url": "Firefox-mozilla-central-nightly-20211003100640",
+                        },
+                        "target.partial-3.mar": {
+                            "buildid": "20211002213629",
+                            "mar_url": "Firefox-mozilla-central-nightly-20211002213629",
+                        },
+                        "target.partial-4.mar": {
+                            "buildid": "20211002095048",
+                            "mar_url": "Firefox-mozilla-central-nightly-20211002095048",
+                        },
+                    }
+                }
+            },
+        )
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_runnable_jobs.py b/taskcluster/gecko_taskgraph/test/test_util_runnable_jobs.py
new file mode 100644
index 0000000000..993521b830
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_runnable_jobs.py
@@ -0,0 +1,76 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import unittest
+
+from mozunit import main
+from taskgraph.graph import Graph
+from taskgraph.task import Task
+from taskgraph.taskgraph import TaskGraph
+
+from gecko_taskgraph.decision import full_task_graph_to_runnable_jobs
+
+
+class TestRunnableJobs(unittest.TestCase):
+
+    tasks = [
+        {
+            "kind": "build",
+            "label": "a",
+            "attributes": {},
+            "task": {
+                "extra": {"treeherder": {"symbol": "B"}},
+            },
+        },
+        {
+            "kind": "test",
+            "label": "b",
+            "attributes": {},
+            "task": {
+                "extra": {
+                    "treeherder": {
+                        "collection": {"opt": True},
+                        "groupName": "Some group",
+                        "groupSymbol": "GS",
+                        "machine": {"platform": "linux64"},
+                        "symbol": "t",
+                    }
+                },
+            },
+        },
+    ]
+
+    def make_taskgraph(self, tasks):
+        label_to_taskid = {k: k + "-tid" for k in tasks}
+        for label, task_id in label_to_taskid.items():
+            tasks[label].task_id = task_id
+        graph = Graph(nodes=set(tasks), edges=set())
+        taskgraph = TaskGraph(tasks, graph)
+        return taskgraph, label_to_taskid
+
+    def test_taskgraph_to_runnable_jobs(self):
+        tg, label_to_taskid = self.make_taskgraph(
+            {t["label"]: Task(**t) for t in self.tasks[:]}
+        )
+
+        res = full_task_graph_to_runnable_jobs(tg.to_json())
+
+        self.assertEqual(
+            res,
+            {
+                "a": {"symbol": "B"},
+                "b": {
+                    "collection": {"opt": True},
+                    "groupName": "Some group",
+                    "groupSymbol": "GS",
+                    "symbol": "t",
+                    "platform": "linux64",
+                },
+            },
+        )
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_templates.py b/taskcluster/gecko_taskgraph/test/test_util_templates.py
new file mode 100644
index 0000000000..edfb13a277
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_templates.py
@@ -0,0 +1,79 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import unittest
+
+import mozunit
+
+from gecko_taskgraph.util.templates import merge, merge_to
+
+
+class MergeTest(unittest.TestCase):
+    def test_merge_to_dicts(self):
+        source = {"a": 1, "b": 2}
+        dest = {"b": "20", "c": 30}
+        expected = {
+            "a": 1,  # source only
+            "b": 2,  # source overrides dest
+            "c": 30,  # dest only
+        }
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_to_lists(self):
+        source = {"x": [3, 4]}
+        dest = {"x": [1, 2]}
+        expected = {"x": [1, 2, 3, 4]}  # dest first
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_diff_types(self):
+        source = {"x": [1, 2]}
+        dest = {"x": "abc"}
+        expected = {"x": [1, 2]}  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge(self):
+        first = {"a": 1, "b": 2, "d": 11}
+        second = {"b": 20, "c": 30}
+        third = {"c": 300, "d": 400}
+        expected = {
+            "a": 1,
+            "b": 20,
+            "c": 300,
+            "d": 400,
+        }
+        self.assertEqual(merge(first, second, third), expected)
+
+        # inputs haven't changed..
+        self.assertEqual(first, {"a": 1, "b": 2, "d": 11})
+        self.assertEqual(second, {"b": 20, "c": 30})
+        self.assertEqual(third, {"c": 300, "d": 400})
+
+    def test_merge_by(self):
+        source = {
+            "x": "abc",
+            "y": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}},
+        }
+        dest = {"y": {"by-foo": {"purple": "rain", "default": ["x", "y", "z"]}}}
+        expected = {
+            "x": "abc",
+            "y": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}},
+        }  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_multiple_by(self):
+        source = {"x": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}}}
+        dest = {"x": {"by-bar": {"purple": "rain", "default": ["x", "y", "z"]}}}
+        expected = {
+            "x": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}}
+        }  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+
+
+if __name__ == "__main__":
+    mozunit.main()
diff --git a/taskcluster/gecko_taskgraph/test/test_util_verify.py b/taskcluster/gecko_taskgraph/test/test_util_verify.py
new file mode 100644
index 0000000000..e2f774a315
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/test/test_util_verify.py
@@ -0,0 +1,149 @@
+#  This Source Code Form is subject to the terms of the Mozilla Public
+#  License, v. 2.0. If a copy of the MPL was not distributed with this
+#  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+There are some basic tests run as part of the Decision task to make sure
+documentation exists for taskgraph functionality.
+These functions are defined in gecko_taskgraph.generator and call
+gecko_taskgraph.util.verify.verify_docs with different parameters to do the
+actual checking.
+"""
+
+
+import os.path
+
+import pytest
+from mozunit import main
+
+import gecko_taskgraph.util.verify
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.util.verify import DocPaths, verify_docs
+
+FF_DOCS_BASE = os.path.join(GECKO, "taskcluster", "docs")
+EXTRA_DOCS_BASE = os.path.abspath(os.path.join(os.path.dirname(__file__), "docs"))
+
+
+@pytest.fixture
+def mock_single_doc_path(monkeypatch):
+    """Set a single path containing documentation"""
+    mocked_documentation_paths = DocPaths()
+    mocked_documentation_paths.add(FF_DOCS_BASE)
+    monkeypatch.setattr(
+        gecko_taskgraph.util.verify, "documentation_paths", mocked_documentation_paths
+    )
+
+
+@pytest.fixture
+def mock_two_doc_paths(monkeypatch):
+    """Set two paths containing documentation"""
+    mocked_documentation_paths = DocPaths()
+    mocked_documentation_paths.add(FF_DOCS_BASE)
+    mocked_documentation_paths.add(EXTRA_DOCS_BASE)
+    monkeypatch.setattr(
+        gecko_taskgraph.util.verify, "documentation_paths", mocked_documentation_paths
+    )
+
+
+@pytest.mark.usefixtures("mock_single_doc_path")
+class PyTestSingleDocPath:
+    """
+    Taskcluster documentation for Firefox is in a single directory. Check the tests
+    running at build time to make sure documentation exists, actually work themselves.
+    """
+
+    def test_heading(self):
+        """
+        Look for a headings in filename matching identifiers. This is used when making sure
+        documentation exists for kinds and attributes.
+        """
+        verify_docs(
+            filename="kinds.rst",
+            identifiers=["build", "packages", "toolchain"],
+            appearing_as="heading",
+        )
+        with pytest.raises(Exception, match="missing from doc file"):
+            verify_docs(
+                filename="kinds.rst",
+                identifiers=["build", "packages", "badvalue"],
+                appearing_as="heading",
+            )
+
+    def test_inline_literal(self):
+        """
+        Look for inline-literals in filename. Used when checking documentation for decision
+        task parameters and run-using functions.
+        """
+        verify_docs(
+            filename="parameters.rst",
+            identifiers=["base_repository", "head_repository", "owner"],
+            appearing_as="inline-literal",
+        )
+        with pytest.raises(Exception, match="missing from doc file"):
+            verify_docs(
+                filename="parameters.rst",
+                identifiers=["base_repository", "head_repository", "badvalue"],
+                appearing_as="inline-literal",
+            )
+
+
+@pytest.mark.usefixtures("mock_two_doc_paths")
+class PyTestTwoDocPaths:
+    """
+    Thunderbird extends Firefox's taskgraph with additional kinds. The documentation
+    for Thunderbird kinds are in its repository, and documentation_paths will have
+    two places to look for files. Run the same tests as for a single documentation
+    path, and cover additional possible scenarios.
+    """
+
+    def test_heading(self):
+        """
+        Look for a headings in filename matching identifiers. This is used when
+        making sure documentation exists for kinds and attributes.
+        The first test looks for headings that are all within the first doc path,
+        the second test is new and has a heading found in the second path.
+        The final check has a identifier that will not match and should
+        produce an error.
+        """
+        verify_docs(
+            filename="kinds.rst",
+            identifiers=["build", "packages", "toolchain"],
+            appearing_as="heading",
+        )
+        verify_docs(
+            filename="kinds.rst",
+            identifiers=["build", "packages", "newkind"],
+            appearing_as="heading",
+        )
+        with pytest.raises(Exception, match="missing from doc file"):
+            verify_docs(
+                filename="kinds.rst",
+                identifiers=["build", "packages", "badvalue"],
+                appearing_as="heading",
+            )
+
+    def test_inline_literal(self):
+        """
+        Look for inline-literals in filename. Used when checking documentation for decision
+        task parameters and run-using functions. As with the heading tests,
+        the second check looks for an identifier in the added documentation path.
+        """
+        verify_docs(
+            filename="parameters.rst",
+            identifiers=["base_repository", "head_repository", "owner"],
+            appearing_as="inline-literal",
+        )
+        verify_docs(
+            filename="parameters.rst",
+            identifiers=["base_repository", "head_repository", "newparameter"],
+            appearing_as="inline-literal",
+        )
+        with pytest.raises(Exception, match="missing from doc file"):
+            verify_docs(
+                filename="parameters.rst",
+                identifiers=["base_repository", "head_repository", "badvalue"],
+                appearing_as="inline-literal",
+            )
+
+
+if __name__ == "__main__":
+    main()
diff --git a/taskcluster/gecko_taskgraph/transforms/__init__.py b/taskcluster/gecko_taskgraph/transforms/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/__init__.py
diff --git a/taskcluster/gecko_taskgraph/transforms/artifact.py b/taskcluster/gecko_taskgraph/transforms/artifact.py
new file mode 100644
index 0000000000..559148f7b4
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/artifact.py
@@ -0,0 +1,116 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Apply different expiration dates to different artifacts based on a manifest file (artifacts.yml)
+"""
+import logging
+import os
+import sys
+
+import yaml
+from taskgraph.transforms.base import TransformSequence
+from yaml import YAMLError
+
+from gecko_taskgraph.transforms.job.common import get_expiration
+from gecko_taskgraph.util.workertypes import worker_type_implementation
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+def read_artifact_manifest(manifest_path):
+    """Read the artifacts.yml manifest file and return it."""
+    # logger.info(f"The current directory is {os.getcwd()}")
+    try:
+        with open(manifest_path, "r") as ymlf:
+            yml = yaml.safe_load(ymlf.read())
+            return yml
+    except YAMLError as ye:
+        err = 'Failed to parse manifest "{manifest_path}". Invalid Yaml:'
+        err += ye
+        raise SystemExit(err)
+    except FileNotFoundError:
+        err = f'Failed to load manifest "{manifest_path}". File not found'
+        raise SystemExit(err)
+    except PermissionError:
+        err = f'Failed to load manifest "{manifest_path}". Permission Error'
+        raise SystemExit(err)
+
+
+@transforms.add
+def set_artifact_expiration(config, jobs):
+    """Set the expiration for certain artifacts based on a manifest file."""
+    """---
+       win:
+         - build_resources.json: short
+
+       linux:
+         - target.crashreporter-symbols-full.tar.zst: medium
+    """
+    transform_dir = os.path.dirname(__file__)
+    manifest = read_artifact_manifest(os.path.join(transform_dir, "artifacts.yml"))
+
+    for job in jobs:
+        try:
+            platform = job["attributes"]["build_platform"]
+        except KeyError:
+            err = "Tried to get build_platfrom for job, but it does not exist. Exiting."
+            raise SystemExit(err)
+        if "worker" in job:
+            if "env" in job["worker"]:
+                if isinstance(job["worker"]["env"], dict):
+                    job["worker"]["env"]["MOZ_ARTIFACT_PLATFORM"] = platform
+                else:
+                    raise SystemExit(
+                        f"Expected env to be a dict, but it was {type(job['worker']['env'])}"
+                    )
+            if "artifacts" in job["worker"]:
+                plat = platform.lower()
+                if "plain" in plat or "ccov" in plat or "rusttest" in plat:
+                    art_dict = None
+                elif (
+                    plat == "toolchain-wasm32-wasi-compiler-rt-trunk"
+                    or plat == "toolchain-linux64-x64-compiler-rt-trunk"
+                    or plat == "toolchain-linux64-x86-compiler-rt-trunk"
+                    or plat == "android-geckoview-docs"
+                ):
+                    art_dict = None
+                elif plat.startswith("win"):
+                    art_dict = manifest["win"]
+                elif plat.startswith("linux"):
+                    art_dict = manifest["linux"]
+                elif plat.startswith("mac"):
+                    art_dict = manifest["macos"]
+                elif plat.startswith("android"):
+                    art_dict = manifest["android"]
+                else:
+                    print(
+                        'The platform name "{plat}" didn\'t start with',
+                        '"win", "mac", "android", or "linux".',
+                        file=sys.stderr,
+                    )
+                    art_dict = None
+                worker_implementation, _ = worker_type_implementation(
+                    config.graph_config, config.params, job["worker-type"]
+                )
+                if worker_implementation == "docker-worker":
+                    artifact_dest = "/builds/worker/cidata/{}"
+                else:
+                    artifact_dest = "cidata/{}"
+
+                if art_dict is not None:
+                    for art_name in art_dict.keys():
+                        # The 'artifacts' key of a job is a list at this stage.
+                        # So, must append a new dict to the list
+                        expiry_policy = art_dict[art_name]
+                        expires = get_expiration(config, policy=expiry_policy)
+                        new_art = {
+                            "name": f"public/cidata/{art_name}",
+                            "path": artifact_dest.format(art_name),
+                            "type": "file",
+                            "expires-after": expires,
+                        }
+                        job["worker"]["artifacts"].append(new_art)
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/artifacts.yml b/taskcluster/gecko_taskgraph/transforms/artifacts.yml
new file mode 100644
index 0000000000..b41c657283
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/artifacts.yml
@@ -0,0 +1,16 @@
+---
+win:
+    target.crashreporter-symbols-full.tar.zst: shortest
+    sccache.log: shortest
+
+linux:
+    target.crashreporter-symbols-full.tar.zst: shortest
+    sccache.log: shortest
+
+macos:
+    target.crashreporter-symbols-full.tar.zst: shortest
+    sccache.log: shortest
+
+android:
+    target.crashreporter-symbols-full.tar.zst: shortest
+    sccache.log: shortest
diff --git a/taskcluster/gecko_taskgraph/transforms/attribution.py b/taskcluster/gecko_taskgraph/transforms/attribution.py
new file mode 100644
index 0000000000..935c274c03
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/attribution.py
@@ -0,0 +1,32 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def stub_installer(config, jobs):
+    """Not all windows builds come with a stub installer (only win32, and not
+    on esr), so conditionally add it here based on our dependency's
+    stub-installer attribute."""
+    for job in jobs:
+        dep_name, dep_label = next(iter(job["dependencies"].items()))
+        dep_task = config.kind_dependencies_tasks[dep_label]
+        if dep_task.attributes.get("stub-installer"):
+            locale = job["attributes"].get("locale")
+            if locale:
+                artifact = f"{locale}/target.stub-installer.exe"
+            else:
+                artifact = "target.stub-installer.exe"
+            job["fetches"][dep_name].append(artifact)
+            job["run"]["command"] += [
+                "--input",
+                "/builds/worker/fetches/target.stub-installer.exe",
+            ]
+            job["attributes"]["release_artifacts"].append(
+                "public/build/target.stub-installer.exe"
+            )
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/balrog_submit.py b/taskcluster/gecko_taskgraph/transforms/balrog_submit.py
new file mode 100644
index 0000000000..067600f0cb
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/balrog_submit.py
@@ -0,0 +1,138 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the per-locale balrog task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import replace_group
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+
+balrog_description_schema = schema.extend(
+    {
+        # unique label to describe this balrog task, defaults to balrog-{dep.label}
+        Optional("label"): str,
+        Optional(
+            "update-no-wnp",
+            description="Whether the parallel `-No-WNP` blob should be updated as well.",
+        ): optionally_keyed_by("release-type", bool),
+        # treeherder is allowed here to override any defaults we use for beetmover.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("attributes"): task_description_schema["attributes"],
+        # Shipping product / phase
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+
+transforms = TransformSequence()
+transforms.add_validate(balrog_description_schema)
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by platform, etc."""
+    fields = [
+        "update-no-wnp",
+    ]
+    for job in jobs:
+        label = job.get("dependent-task", object).__dict__.get("label", "?no-label?")
+        for field in fields:
+            resolve_keyed_by(
+                item=job,
+                field=field,
+                item_name=label,
+                **{
+                    "project": config.params["project"],
+                    "release-type": config.params["release_type"],
+                },
+            )
+        yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "c-Up(N)")
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault(
+            "tier", dep_job.task.get("extra", {}).get("treeherder", {}).get("tier", 1)
+        )
+        treeherder.setdefault("kind", "build")
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        treeherder_job_symbol = dep_job.task["extra"]["treeherder"]["symbol"]
+        treeherder["symbol"] = replace_group(treeherder_job_symbol, "c-Up")
+
+        if dep_job.attributes.get("locale"):
+            attributes["locale"] = dep_job.attributes.get("locale")
+
+        label = job["label"]
+
+        description = (
+            "Balrog submission for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        upstream_artifacts = [
+            {
+                "taskId": {"task-reference": "<beetmover>"},
+                "taskType": "beetmover",
+                "paths": ["public/manifest.json"],
+            }
+        ]
+
+        dependencies = {"beetmover": dep_job.label}
+        for kind_dep in config.kind_dependencies_tasks.values():
+            if (
+                kind_dep.kind == "startup-test"
+                and kind_dep.attributes["build_platform"]
+                == attributes.get("build_platform")
+                and kind_dep.attributes["build_type"] == attributes.get("build_type")
+                and kind_dep.attributes.get("shipping_product")
+                == job.get("shipping-product")
+            ):
+                dependencies["startup-test"] = kind_dep.label
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "balrog",
+            "worker": {
+                "implementation": "balrog",
+                "upstream-artifacts": upstream_artifacts,
+                "balrog-action": "v2-submit-locale",
+                "suffixes": ["", "-No-WNP"] if job.get("update-no-wnp") else [""],
+            },
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "shipping-phase": job.get("shipping-phase", "promote"),
+            "shipping-product": job.get("shipping-product"),
+        }
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/balrog_toplevel.py b/taskcluster/gecko_taskgraph/transforms/balrog_toplevel.py
new file mode 100644
index 0000000000..6b06758f69
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/balrog_toplevel.py
@@ -0,0 +1,42 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+from mozilla_version.gecko import GeckoVersion
+from mozrelease.balrog import generate_update_properties
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.yaml import load_yaml
+
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def generate_update_line(config, jobs):
+    """Resolve fields that can be keyed by platform, etc."""
+    release_config = get_release_config(config)
+    for job in jobs:
+        config_file = job.pop("whats-new-config")
+        update_config = load_yaml(config_file)
+
+        product = job["shipping-product"]
+        if product == "devedition":
+            product = "firefox"
+        job["worker"]["update-line"] = {}
+        for blob_type, suffix in [("wnp", ""), ("no-wnp", "-No-WNP")]:
+            context = {
+                "release-type": config.params["release_type"],
+                "product": product,
+                "version": GeckoVersion.parse(release_config["appVersion"]),
+                "blob-type": blob_type,
+                "build-id": config.params["moz_build_date"],
+            }
+            job["worker"]["update-line"][suffix] = generate_update_properties(
+                context, update_config
+            )
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover.py b/taskcluster/gecko_taskgraph/transforms/beetmover.py
new file mode 100644
index 0000000000..93818707dd
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover.py
@@ -0,0 +1,165 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import replace_group
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+transforms = TransformSequence()
+
+beetmover_description_schema = schema.extend(
+    {
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Optional("label"): str,
+        # treeherder is allowed here to override any defaults we use for beetmover.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        # locale is passed only for l10n beetmoving
+        Optional("locale"): str,
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+
+transforms.add_validate(beetmover_description_schema)
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault(
+            "symbol", replace_group(dep_job.task["extra"]["treeherder"]["symbol"], "BM")
+        )
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault(
+            "tier", dep_job.task.get("extra", {}).get("treeherder", {}).get("tier", 1)
+        )
+        treeherder.setdefault("kind", "build")
+        label = job["label"]
+        description = (
+            "Beetmover submission for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        dependencies = {dep_job.kind: dep_job.label}
+
+        # XXX release snap-repackage has a variable number of dependencies, depending on how many
+        # "post-beetmover-dummy" jobs there are in the graph.
+        if dep_job.kind != "release-snap-repackage" and len(dep_job.dependencies) > 1:
+            raise NotImplementedError(
+                "Can't beetmove a signing task with multiple dependencies"
+            )
+        signing_dependencies = dep_job.dependencies
+        dependencies.update(signing_dependencies)
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+
+        if job.get("locale"):
+            attributes["locale"] = job["locale"]
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "shipping-phase": job["shipping-phase"],
+        }
+
+        yield task
+
+
+def craft_release_properties(config, job):
+    params = config.params
+    build_platform = job["attributes"]["build_platform"]
+    build_platform = build_platform.replace("-shippable", "")
+    if build_platform.endswith("-source"):
+        build_platform = build_platform.replace("-source", "-release")
+
+    # XXX This should be explicitly set via build attributes or something
+    if "android" in job["label"] or "fennec" in job["label"]:
+        app_name = "Fennec"
+    elif config.graph_config["trust-domain"] == "comm":
+        app_name = "Thunderbird"
+    else:
+        # XXX Even DevEdition is called Firefox
+        app_name = "Firefox"
+
+    return {
+        "app-name": app_name,
+        "app-version": params["app_version"],
+        "branch": params["project"],
+        "build-id": params["moz_build_date"],
+        "hash-type": "sha512",
+        "platform": build_platform,
+    }
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        valid_beetmover_job = len(job["dependencies"]) == 2 and any(
+            ["signing" in j for j in job["dependencies"]]
+        )
+        # XXX release snap-repackage has a variable number of dependencies, depending on how many
+        # "post-beetmover-dummy" jobs there are in the graph.
+        if "-snap-" not in job["label"] and not valid_beetmover_job:
+            raise NotImplementedError("Beetmover must have two dependencies.")
+
+        locale = job["attributes"].get("locale")
+        platform = job["attributes"]["build_platform"]
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform, locale
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform, locale=locale
+            ),
+        }
+
+        if locale:
+            worker["locale"] = locale
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_apt.py b/taskcluster/gecko_taskgraph/transforms/beetmover_apt.py
new file mode 100644
index 0000000000..8c56f1a968
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_apt.py
@@ -0,0 +1,114 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+from itertools import islice
+
+from taskgraph import MAX_DEPENDENCIES
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.platforms import architecture
+from gecko_taskgraph.util.scriptworker import (
+    generate_artifact_registry_gcs_sources,
+    get_beetmover_apt_repo_scope,
+    get_beetmover_repo_action_scope,
+)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def beetmover_apt(config, tasks):
+    product = (
+        "firefox"
+        if not config.params["release_type"]  # try
+        or config.params["release_type"] == "nightly"
+        else config.params["release_product"]
+    )
+    filtered_tasks = filter_beetmover_apt_tasks(tasks, product)
+    # There are too many beetmover-repackage dependencies for a single task
+    # and we hit the taskgraph dependencies limit.
+    # To work around this limitation, we chunk the would be task
+    # into tasks dependendent on, at most, half of MAX_DEPENDENCIES.
+    batches = batched(filtered_tasks, MAX_DEPENDENCIES // 2)
+    for index, batch in enumerate(batches):
+        dependencies = {}
+        gcs_sources = []
+        for task in batch:
+            dep = task["primary-dependency"]
+            dependencies[dep.label] = dep.label
+            gcs_sources.extend(generate_artifact_registry_gcs_sources(dep))
+        description = f"Batch {index + 1} of beetmover APT submissions for the {config.params['release_type']} .deb packages"
+        platform = "firefox-release/opt"
+        treeherder = {
+            "platform": platform,
+            "tier": 1,
+            "kind": "other",
+            "symbol": f"BM-apt(batch-{index + 1})",
+        }
+        apt_repo_scope = get_beetmover_apt_repo_scope(config)
+        repo_action_scope = get_beetmover_repo_action_scope(config)
+        attributes = {
+            "required_signoffs": ["mar-signing"],
+            "shippable": True,
+            "shipping_product": product,
+        }
+        task = {
+            "label": f"{config.kind}-{index + 1}-{platform}",
+            "description": description,
+            "worker-type": "beetmover",
+            "treeherder": treeherder,
+            "scopes": [apt_repo_scope, repo_action_scope],
+            "attributes": attributes,
+            "shipping-phase": "ship",
+            "shipping-product": product,
+            "dependencies": dependencies,
+        }
+        worker = {
+            "implementation": "beetmover-import-from-gcs-to-artifact-registry",
+            "product": product,
+            "gcs-sources": gcs_sources,
+        }
+        task["worker"] = worker
+        yield task
+
+
+def batched(iterable, n):
+    "Batch data into tuples of length n. The last batch may be shorter."
+    # batched('ABCDEFG', 3) --> ABC DEF G
+    if n < 1:
+        raise ValueError("n must be at least one")
+    it = iter(iterable)
+    batch = tuple(islice(it, n))
+    while batch:
+        yield batch
+        batch = tuple(islice(it, n))
+
+
+def filter_beetmover_apt_tasks(tasks, product):
+    return (task for task in tasks if filter_beetmover_apt_task(task, product))
+
+
+def filter_beetmover_apt_task(task, product):
+    # We only create beetmover-apt tasks for l10n beetmover-repackage tasks that
+    # beetmove langpack .deb packages. The langpack .deb packages support all
+    # architectures, so we generate them only on x86_64 tasks.
+    return (
+        is_x86_64_l10n_task(task) or is_not_l10n_task(task)
+    ) and is_task_for_product(task, product)
+
+
+def is_x86_64_l10n_task(task):
+    dep = task["primary-dependency"]
+    locale = dep.attributes.get("locale")
+    return locale and architecture(dep.attributes["build_platform"]) == "x86_64"
+
+
+def is_not_l10n_task(task):
+    dep = task["primary-dependency"]
+    locale = dep.attributes.get("locale")
+    return not locale
+
+
+def is_task_for_product(task, product):
+    dep = task["primary-dependency"]
+    return dep.attributes.get("shipping_product") == product
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_checksums.py b/taskcluster/gecko_taskgraph/transforms/beetmover_checksums.py
new file mode 100644
index 0000000000..f595854a80
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_checksums.py
@@ -0,0 +1,133 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the checksums signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import replace_group
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+beetmover_checksums_description_schema = schema.extend(
+    {
+        Required("attributes"): {str: object},
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("locale"): str,
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_checksums_description_schema)
+
+
+@transforms.add
+def make_beetmover_checksums_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault(
+            "symbol",
+            replace_group(dep_job.task["extra"]["treeherder"]["symbol"], "BMcs"),
+        )
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault(
+            "tier", dep_job.task.get("extra", {}).get("treeherder", {}).get("tier", 1)
+        )
+        treeherder.setdefault("kind", "build")
+
+        label = job["label"]
+        build_platform = attributes.get("build_platform")
+
+        description = (
+            "Beetmover submission of checksums for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=build_platform,
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        extra = {}
+        if "devedition" in build_platform:
+            extra["product"] = "devedition"
+        else:
+            extra["product"] = "firefox"
+
+        dependencies = {dep_job.kind: dep_job.label}
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+
+        if dep_job.attributes.get("locale"):
+            treeherder["symbol"] = "BMcs({})".format(dep_job.attributes.get("locale"))
+            attributes["locale"] = dep_job.attributes.get("locale")
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "extra": extra,
+        }
+
+        if "shipping-phase" in job:
+            task["shipping-phase"] = job["shipping-phase"]
+
+        if "shipping-product" in job:
+            task["shipping-product"] = job["shipping-product"]
+
+        yield task
+
+
+@transforms.add
+def make_beetmover_checksums_worker(config, jobs):
+    for job in jobs:
+        locale = job["attributes"].get("locale")
+        platform = job["attributes"]["build_platform"]
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform, locale
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform, locale=locale
+            ),
+        }
+
+        if locale:
+            worker["locale"] = locale
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_emefree_checksums.py b/taskcluster/gecko_taskgraph/transforms/beetmover_emefree_checksums.py
new file mode 100644
index 0000000000..9c2b49b6c5
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_emefree_checksums.py
@@ -0,0 +1,139 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform release-beetmover-source-checksums into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+
+beetmover_checksums_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("extra"): object,
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_checksums_description_schema)
+
+
+@transforms.add
+def make_beetmover_checksums_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+        build_platform = attributes.get("build_platform")
+        if not build_platform:
+            raise Exception("Cannot find build platform!")
+        repack_id = dep_job.task.get("extra", {}).get("repack_id")
+        if not repack_id:
+            raise Exception("Cannot find repack id!")
+
+        label = dep_job.label.replace("beetmover-", "beetmover-checksums-")
+        description = (
+            "Beetmove checksums for repack_id '{repack_id}' for build '"
+            "{build_platform}/{build_type}'".format(
+                repack_id=repack_id,
+                build_platform=build_platform,
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        extra = {}
+        extra["partner_path"] = dep_job.task["payload"]["upstreamArtifacts"][0][
+            "locale"
+        ]
+        extra["repack_id"] = repack_id
+
+        dependencies = {dep_job.kind: dep_job.label}
+        for k, v in dep_job.dependencies.items():
+            if k.startswith("beetmover"):
+                dependencies[k] = v
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "{}/{}".format(
+                dep_job.task["provisionerId"],
+                dep_job.task["workerType"],
+            ),
+            "scopes": dep_job.task["scopes"],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "extra": extra,
+        }
+
+        if "shipping-phase" in job:
+            task["shipping-phase"] = job["shipping-phase"]
+
+        if "shipping-product" in job:
+            task["shipping-product"] = job["shipping-product"]
+
+        yield task
+
+
+def generate_upstream_artifacts(refs, partner_path):
+    # Until bug 1331141 is fixed, if you are adding any new artifacts here that
+    # need to be transfered to S3, please be aware you also need to follow-up
+    # with a beetmover patch in https://github.com/mozilla-releng/beetmoverscript/.
+    # See example in bug 1348286
+    common_paths = [
+        "public/target.checksums",
+    ]
+
+    upstream_artifacts = [
+        {
+            "taskId": {"task-reference": refs["beetmover"]},
+            "taskType": "signing",
+            "paths": common_paths,
+            "locale": f"beetmover-checksums/{partner_path}",
+        }
+    ]
+
+    return upstream_artifacts
+
+
+@transforms.add
+def make_beetmover_checksums_worker(config, jobs):
+    for job in jobs:
+        valid_beetmover_job = len(job["dependencies"]) == 1
+        if not valid_beetmover_job:
+            raise NotImplementedError("Beetmover checksums must have one dependency.")
+
+        refs = {
+            "beetmover": None,
+        }
+        for dependency in job["dependencies"].keys():
+            if dependency.endswith("beetmover"):
+                refs["beetmover"] = f"<{dependency}>"
+        if None in refs.values():
+            raise NotImplementedError(
+                "Beetmover checksums must have a beetmover dependency!"
+            )
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_upstream_artifacts(
+                refs,
+                job["extra"]["partner_path"],
+            ),
+            "partner-public": True,
+        }
+
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_geckoview.py b/taskcluster/gecko_taskgraph/transforms/beetmover_geckoview.py
new file mode 100644
index 0000000000..6eee5954e3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_geckoview.py
@@ -0,0 +1,166 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+
+from copy import deepcopy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import (
+    craft_release_properties as beetmover_craft_release_properties,
+)
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.declarative_artifacts import (
+    get_geckoview_artifact_id,
+    get_geckoview_artifact_map,
+    get_geckoview_upstream_artifacts,
+)
+
+beetmover_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Required("run-on-projects"): task_description_schema["run-on-projects"],
+        Required("run-on-hg-branches"): task_description_schema["run-on-hg-branches"],
+        Optional("bucket-scope"): optionally_keyed_by("release-level", str),
+        Optional("shipping-phase"): optionally_keyed_by(
+            "project", task_description_schema["shipping-phase"]
+        ),
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_description_schema)
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "run-on-hg-branches",
+            item_name=job["label"],
+            project=config.params["project"],
+        )
+        resolve_keyed_by(
+            job,
+            "shipping-phase",
+            item_name=job["label"],
+            project=config.params["project"],
+        )
+        resolve_keyed_by(
+            job,
+            "bucket-scope",
+            item_name=job["label"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        yield job
+
+
+@transforms.add
+def split_maven_packages(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        for package in attributes["maven_packages"]:
+            package_job = deepcopy(job)
+            package_job["maven-package"] = package
+            yield package_job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+
+        treeherder = job.get("treeherder", {})
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault("tier", 2)
+        treeherder.setdefault("kind", "build")
+        package = job["maven-package"]
+        treeherder.setdefault("symbol", f"BM-{package}")
+        label = job["label"]
+        description = (
+            "Beetmover submission for geckoview"
+            "{build_platform}/{build_type}'".format(
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        dependencies = deepcopy(dep_job.dependencies)
+        dependencies[dep_job.kind] = dep_job.label
+
+        if job.get("locale"):
+            attributes["locale"] = job["locale"]
+
+        attributes["run_on_hg_branches"] = job["run-on-hg-branches"]
+
+        task = {
+            "label": f"{package}-{label}",
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [
+                job["bucket-scope"],
+                "project:releng:beetmover:action:push-to-maven",
+            ],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": job["run-on-projects"],
+            "treeherder": treeherder,
+            "shipping-phase": job["shipping-phase"],
+            "maven-package": package,
+        }
+
+        yield task
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        job["worker"] = {
+            "artifact-map": get_geckoview_artifact_map(config, job),
+            "implementation": "beetmover-maven",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": get_geckoview_upstream_artifacts(
+                config, job, job["maven-package"]
+            ),
+        }
+        del job["maven-package"]
+
+        yield job
+
+
+def craft_release_properties(config, job):
+    release_properties = beetmover_craft_release_properties(config, job)
+
+    release_properties["artifact-id"] = get_geckoview_artifact_id(
+        config,
+        job["attributes"]["build_platform"],
+        job["maven-package"],
+        job["attributes"].get("update-channel"),
+    )
+    release_properties["app-name"] = "geckoview"
+
+    return release_properties
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_langpack_checksums.py b/taskcluster/gecko_taskgraph/transforms/beetmover_langpack_checksums.py
new file mode 100644
index 0000000000..9318ed29d4
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_langpack_checksums.py
@@ -0,0 +1,128 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform release-beetmover-langpack-checksums into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import inherit_treeherder_from_dep
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+beetmover_checksums_description_schema = schema.extend(
+    {
+        Required("attributes"): {str: object},
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("locale"): str,
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_checksums_description_schema)
+
+
+@transforms.add
+def make_beetmover_checksums_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault(
+            "symbol", "BMcslang(N{})".format(attributes.get("l10n_chunk", ""))
+        )
+
+        label = job["label"]
+        build_platform = attributes.get("build_platform")
+
+        description = "Beetmover submission of checksums for langpack files"
+
+        extra = {}
+        if "devedition" in build_platform:
+            extra["product"] = "devedition"
+        else:
+            extra["product"] = "firefox"
+
+        dependencies = {dep_job.kind: dep_job.label}
+        for k, v in dep_job.dependencies.items():
+            if k.startswith("beetmover"):
+                dependencies[k] = v
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        if "chunk_locales" in dep_job.attributes:
+            attributes["chunk_locales"] = dep_job.attributes["chunk_locales"]
+        attributes.update(job.get("attributes", {}))
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "extra": extra,
+        }
+
+        if "shipping-phase" in job:
+            task["shipping-phase"] = job["shipping-phase"]
+
+        if "shipping-product" in job:
+            task["shipping-product"] = job["shipping-product"]
+
+        yield task
+
+
+@transforms.add
+def make_beetmover_checksums_worker(config, jobs):
+    for job in jobs:
+        valid_beetmover_job = len(job["dependencies"]) == 1
+        if not valid_beetmover_job:
+            raise NotImplementedError("Beetmover checksums must have one dependency.")
+
+        locales = job["attributes"].get("chunk_locales")
+        platform = job["attributes"]["build_platform"]
+
+        refs = {
+            "beetmover": None,
+        }
+        for dependency in job["dependencies"].keys():
+            if dependency.startswith("release-beetmover"):
+                refs["beetmover"] = f"<{dependency}>"
+        if None in refs.values():
+            raise NotImplementedError(
+                "Beetmover checksums must have a beetmover dependency!"
+            )
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform, locales
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform, locale=locales
+            ),
+        }
+
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_push_to_release.py b/taskcluster/gecko_taskgraph/transforms/beetmover_push_to_release.py
new file mode 100644
index 0000000000..b6307d93cf
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_push_to_release.py
@@ -0,0 +1,93 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover-push-to-release task into a task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, taskref_or_string
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.scriptworker import (
+    add_scope_prefix,
+    get_beetmover_bucket_scope,
+)
+
+beetmover_push_to_release_description_schema = Schema(
+    {
+        Required("name"): str,
+        Required("product"): str,
+        Required("treeherder-platform"): str,
+        Optional("attributes"): {str: object},
+        Optional("job-from"): task_description_schema["job-from"],
+        Optional("run"): {str: object},
+        Optional("run-on-projects"): task_description_schema["run-on-projects"],
+        Optional("dependencies"): {str: taskref_or_string},
+        Optional("index"): {str: str},
+        Optional("routes"): [str],
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Required("shipping-product"): task_description_schema["shipping-product"],
+        Optional("extra"): task_description_schema["extra"],
+        Optional("worker"): {
+            Optional("max-run-time"): int,
+        },
+    }
+)
+
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_push_to_release_description_schema)
+
+
+@transforms.add
+def make_beetmover_push_to_release_description(config, jobs):
+    for job in jobs:
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "Rel(BM-C)")
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+        treeherder.setdefault("platform", job["treeherder-platform"])
+
+        label = job["name"]
+        description = "Beetmover push to release for '{product}'".format(
+            product=job["product"]
+        )
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = add_scope_prefix(config, "beetmover:action:push-to-releases")
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "product": job["product"],
+            "dependencies": job["dependencies"],
+            "attributes": job.get("attributes", {}),
+            "run-on-projects": job.get("run-on-projects"),
+            "treeherder": treeherder,
+            "shipping-phase": job.get("shipping-phase", "push"),
+            "shipping-product": job.get("shipping-product"),
+            "routes": job.get("routes", []),
+            "extra": job.get("extra", {}),
+            "worker": job.get("worker", {}),
+        }
+
+        yield task
+
+
+@transforms.add
+def make_beetmover_push_to_release_worker(config, jobs):
+    for job in jobs:
+        worker = {
+            "implementation": "beetmover-push-to-release",
+            "product": job["product"],
+        }
+        if job.get("worker", {}).get("max-run-time"):
+            worker["max-run-time"] = job["worker"]["max-run-time"]
+        job["worker"] = worker
+        del job["product"]
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_repackage.py b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage.py
new file mode 100644
index 0000000000..a1ce911b9f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage.py
@@ -0,0 +1,327 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_prefix
+from taskgraph.util.treeherder import inherit_treeherder_from_dep, replace_group
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.multi_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.partials import (
+    get_balrog_platform_name,
+    get_partials_artifacts_from_params,
+    get_partials_info_from_params,
+)
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_partials_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+logger = logging.getLogger(__name__)
+
+
+beetmover_description_schema = schema.extend(
+    {
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Required("label"): str,
+        # treeherder is allowed here to override any defaults we use for beetmover.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("attributes"): task_description_schema["attributes"],
+        # locale is passed only for l10n beetmoving
+        Optional("locale"): str,
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        # Optional until we fix asan (run_on_projects?)
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_description_schema)
+
+
+def get_task_by_suffix(tasks, suffix):
+    """
+    Given tasks<dict>, returns the key to the task with provided suffix<str>
+    Raises exception if more than one task is found
+
+    Args:
+        tasks (Dict): Map of labels to tasks
+        suffix (str): Suffix for the desired task
+
+    Returns
+        str: The key to the desired task
+    """
+    labels = []
+    for label in tasks.keys():
+        if label.endswith(suffix):
+            labels.append(label)
+    if len(labels) > 1:
+        raise Exception(
+            f"There should only be a single task with suffix: {suffix} - found {len(labels)}"
+        )
+    return labels[0]
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        upstream_symbol = dep_job.task["extra"]["treeherder"]["symbol"]
+        if "build" in job["dependent-tasks"]:
+            upstream_symbol = job["dependent-tasks"]["build"].task["extra"][
+                "treeherder"
+            ]["symbol"]
+        treeherder.setdefault("symbol", replace_group(upstream_symbol, "BMR"))
+        label = job["label"]
+        description = (
+            "Beetmover submission for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        upstream_deps = job["dependent-tasks"]
+
+        signing_name = "build-signing"
+        build_name = "build"
+        repackage_name = "repackage"
+        repackage_signing_name = "repackage-signing"
+        msi_signing_name = "repackage-signing-msi"
+        msix_signing_name = "repackage-signing-shippable-l10n-msix"
+        mar_signing_name = "mar-signing"
+        attribution_name = "attribution"
+        repackage_deb_name = "repackage-deb"
+        if job.get("locale"):
+            signing_name = "shippable-l10n-signing"
+            build_name = "shippable-l10n"
+            repackage_name = "repackage-l10n"
+            repackage_signing_name = "repackage-signing-l10n"
+            mar_signing_name = "mar-signing-l10n"
+            attribution_name = "attribution-l10n"
+            repackage_deb_name = "repackage-deb-l10n"
+
+        # The upstream "signing" task for macosx is either *-mac-signing or *-mac-notarization
+        if attributes.get("build_platform", "").startswith("macosx"):
+            # We use the signing task on level 1 and notarization on level 3
+            if int(config.params.get("level", 0)) < 3:
+                signing_name = get_task_by_suffix(upstream_deps, "-mac-signing")
+            else:
+                signing_name = get_task_by_suffix(upstream_deps, "-mac-notarization")
+            if not signing_name:
+                raise Exception("Could not find upstream kind for mac signing.")
+
+        dependencies = {
+            "build": upstream_deps[build_name],
+            "repackage": upstream_deps[repackage_name],
+            "signing": upstream_deps[signing_name],
+            "mar-signing": upstream_deps[mar_signing_name],
+        }
+        if "partials-signing" in upstream_deps:
+            dependencies["partials-signing"] = upstream_deps["partials-signing"]
+        if msi_signing_name in upstream_deps:
+            dependencies[msi_signing_name] = upstream_deps[msi_signing_name]
+        if msix_signing_name in upstream_deps:
+            dependencies[msix_signing_name] = upstream_deps[msix_signing_name]
+        if repackage_signing_name in upstream_deps:
+            dependencies["repackage-signing"] = upstream_deps[repackage_signing_name]
+        if attribution_name in upstream_deps:
+            dependencies[attribution_name] = upstream_deps[attribution_name]
+        if repackage_deb_name in upstream_deps:
+            dependencies[repackage_deb_name] = upstream_deps[repackage_deb_name]
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+        if job.get("locale"):
+            attributes["locale"] = job["locale"]
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "shipping-phase": job["shipping-phase"],
+            "shipping-product": job.get("shipping-product"),
+        }
+
+        yield task
+
+
+def generate_partials_upstream_artifacts(job, artifacts, platform, locale=None):
+    artifact_prefix = get_artifact_prefix(job)
+    if locale and locale != "en-US":
+        artifact_prefix = f"{artifact_prefix}/{locale}"
+
+    upstream_artifacts = [
+        {
+            "taskId": {"task-reference": "<partials-signing>"},
+            "taskType": "signing",
+            "paths": [f"{artifact_prefix}/{path}" for path, _ in artifacts],
+            "locale": locale or "en-US",
+        }
+    ]
+
+    return upstream_artifacts
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        locale = job["attributes"].get("locale")
+        platform = job["attributes"]["build_platform"]
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform, locale
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform, locale=locale
+            ),
+        }
+
+        if locale:
+            worker["locale"] = locale
+        job["worker"] = worker
+
+        yield job
+
+
+@transforms.add
+def strip_unwanted_langpacks_from_worker(config, jobs):
+    """Strips out langpacks where we didn't sign them.
+
+    This explicitly deletes langpacks from upstream artifacts and from artifact-maps.
+    Due to limitations in declarative artifacts, doing this was our easiest way right now.
+    """
+    ALWAYS_OK_PLATFORMS = {"linux64-shippable", "linux64-devedition"}
+    OSX_OK_PLATFORMS = {"macosx64-shippable", "macosx64-devedition"}
+    for job in jobs:
+        platform = job["attributes"].get("build_platform")
+        if platform in ALWAYS_OK_PLATFORMS:
+            # No need to strip anything
+            yield job
+            continue
+
+        for map in job["worker"].get("artifact-map", [])[:]:
+            if not any([path.endswith("target.langpack.xpi") for path in map["paths"]]):
+                continue
+            if map["locale"] == "ja-JP-mac":
+                # This locale should only exist on mac
+                assert platform in OSX_OK_PLATFORMS
+                continue
+            # map[paths] is being modified while iterating, so we need to resolve the
+            # ".keys()" iterator up front by throwing it into a list.
+            for path in list(map["paths"].keys()):
+                if path.endswith("target.langpack.xpi"):
+                    del map["paths"][path]
+            if map["paths"] == {}:
+                job["worker"]["artifact-map"].remove(map)
+
+        for artifact in job["worker"].get("upstream-artifacts", []):
+            if not any(
+                [path.endswith("target.langpack.xpi") for path in artifact["paths"]]
+            ):
+                continue
+            if artifact["locale"] == "ja-JP-mac":
+                # This locale should only exist on mac
+                assert platform in OSX_OK_PLATFORMS
+                continue
+            artifact["paths"] = [
+                path
+                for path in artifact["paths"]
+                if not path.endswith("target.langpack.xpi")
+            ]
+            if artifact["paths"] == []:
+                job["worker"]["upstream-artifacts"].remove(artifact)
+
+        yield job
+
+
+@transforms.add
+def make_partials_artifacts(config, jobs):
+    for job in jobs:
+        locale = job["attributes"].get("locale")
+        if not locale:
+            locale = "en-US"
+
+        platform = job["attributes"]["build_platform"]
+
+        if "partials-signing" not in job["dependencies"]:
+            yield job
+            continue
+
+        balrog_platform = get_balrog_platform_name(platform)
+        artifacts = get_partials_artifacts_from_params(
+            config.params.get("release_history"), balrog_platform, locale
+        )
+
+        upstream_artifacts = generate_partials_upstream_artifacts(
+            job, artifacts, balrog_platform, locale
+        )
+
+        job["worker"]["upstream-artifacts"].extend(upstream_artifacts)
+
+        extra = list()
+
+        partials_info = get_partials_info_from_params(
+            config.params.get("release_history"), balrog_platform, locale
+        )
+
+        job["worker"]["artifact-map"].extend(
+            generate_beetmover_partials_artifact_map(
+                config, job, partials_info, platform=platform, locale=locale
+            )
+        )
+
+        for artifact in partials_info:
+            artifact_extra = {
+                "locale": locale,
+                "artifact_name": artifact,
+                "buildid": partials_info[artifact]["buildid"],
+                "platform": balrog_platform,
+            }
+            for rel_attr in ("previousBuildNumber", "previousVersion"):
+                if partials_info[artifact].get(rel_attr):
+                    artifact_extra[rel_attr] = partials_info[artifact][rel_attr]
+            extra.append(artifact_extra)
+
+        job.setdefault("extra", {})
+        job["extra"]["partials"] = extra
+
+        yield job
+
+
+@transforms.add
+def convert_deps(config, jobs):
+    for job in jobs:
+        job["dependencies"] = {
+            name: dep_job.label for name, dep_job in job["dependencies"].items()
+        }
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_l10n.py b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_l10n.py
new file mode 100644
index 0000000000..da2a41ccb3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_l10n.py
@@ -0,0 +1,44 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the signing task into an actual task description.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import join_symbol
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_beetmover_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        locale = dep_job.attributes.get("locale")
+        if not locale:
+            yield job
+            continue
+
+        group = "BMR"
+
+        # add the locale code
+        symbol = locale
+
+        treeherder = {
+            "symbol": join_symbol(group, symbol),
+        }
+
+        beet_description = {
+            "label": job["label"],
+            "primary-dependency": dep_job,
+            "dependent-tasks": job["dependent-tasks"],
+            "attributes": job["attributes"],
+            "treeherder": treeherder,
+            "locale": locale,
+            "shipping-phase": job["shipping-phase"],
+            "shipping-product": job["shipping-product"],
+        }
+        yield beet_description
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_partner.py b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_partner.py
new file mode 100644
index 0000000000..40dc370f33
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_repackage_partner.py
@@ -0,0 +1,326 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+import logging
+from copy import deepcopy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.partners import get_ftp_platform, get_partner_config_by_kind
+from gecko_taskgraph.util.scriptworker import (
+    add_scope_prefix,
+    get_beetmover_bucket_scope,
+)
+
+logger = logging.getLogger(__name__)
+
+
+beetmover_description_schema = schema.extend(
+    {
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Optional("label"): str,
+        Required("partner-bucket-scope"): optionally_keyed_by("release-level", str),
+        Required("partner-public-path"): Any(None, str),
+        Required("partner-private-path"): Any(None, str),
+        Optional("extra"): object,
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("priority"): task_description_schema["priority"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_description_schema)
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "partner-bucket-scope",
+            item_name=job["label"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        repack_id = dep_job.task.get("extra", {}).get("repack_id")
+        if not repack_id:
+            raise Exception("Cannot find repack id!")
+
+        attributes = dep_job.attributes
+        build_platform = attributes.get("build_platform")
+        if not build_platform:
+            raise Exception("Cannot find build platform!")
+
+        label = dep_job.label.replace("repackage-signing-l10n", "beetmover-")
+        label = dep_job.label.replace("repackage-signing-", "beetmover-")
+        label = label.replace("repackage-", "beetmover-")
+        label = label.replace("chunking-dummy-", "beetmover-")
+        description = (
+            "Beetmover submission for repack_id '{repack_id}' for build '"
+            "{build_platform}/{build_type}'".format(
+                repack_id=repack_id,
+                build_platform=build_platform,
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        dependencies = {}
+
+        base_label = "release-partner-repack"
+        if "eme" in config.kind:
+            base_label = "release-eme-free-repack"
+        dependencies["build"] = f"{base_label}-{build_platform}"
+        if "macosx" in build_platform or "win" in build_platform:
+            dependencies["repackage"] = "{}-repackage-{}-{}".format(
+                base_label, build_platform, repack_id.replace("/", "-")
+            )
+        dependencies["repackage-signing"] = "{}-repackage-signing-{}-{}".format(
+            base_label, build_platform, repack_id.replace("/", "-")
+        )
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        task = {
+            "label": label,
+            "description": description,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "shipping-phase": job["shipping-phase"],
+            "shipping-product": job.get("shipping-product"),
+            "partner-private-path": job["partner-private-path"],
+            "partner-public-path": job["partner-public-path"],
+            "partner-bucket-scope": job["partner-bucket-scope"],
+            "extra": {
+                "repack_id": repack_id,
+            },
+        }
+        # we may have reduced the priority for partner jobs, otherwise task.py will set it
+        if job.get("priority"):
+            task["priority"] = job["priority"]
+
+        yield task
+
+
+def populate_scopes_and_worker_type(config, job, bucket_scope, partner_public=False):
+    action_scope = add_scope_prefix(config, "beetmover:action:push-to-partner")
+
+    task = deepcopy(job)
+    task["scopes"] = [bucket_scope, action_scope]
+    task["worker-type"] = "beetmover"
+    task["partner_public"] = partner_public
+    if partner_public:
+        task["label"] = "{}-public".format(task["label"])
+    return task
+
+
+@transforms.add
+def split_public_and_private(config, jobs):
+    public_bucket_scope = get_beetmover_bucket_scope(config)
+    partner_config = get_partner_config_by_kind(config, config.kind)
+
+    for job in jobs:
+        partner_bucket_scope = add_scope_prefix(config, job["partner-bucket-scope"])
+        partner, subpartner, _ = job["extra"]["repack_id"].split("/")
+
+        if partner_config[partner][subpartner].get("upload_to_candidates"):
+            # public
+            yield populate_scopes_and_worker_type(
+                config, job, public_bucket_scope, partner_public=True
+            )
+        else:
+            # private
+            yield populate_scopes_and_worker_type(
+                config, job, partner_bucket_scope, partner_public=False
+            )
+
+
+def generate_upstream_artifacts(
+    job,
+    build_task_ref,
+    repackage_task_ref,
+    repackage_signing_task_ref,
+    platform,
+    repack_id,
+    partner_path,
+    repack_stub_installer=False,
+):
+
+    upstream_artifacts = []
+    artifact_prefix = get_artifact_prefix(job)
+
+    if "linux" in platform:
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": build_task_ref},
+                "taskType": "build",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.tar.bz2"],
+                "locale": partner_path,
+            }
+        )
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": repackage_signing_task_ref},
+                "taskType": "repackage",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.tar.bz2.asc"],
+                "locale": partner_path,
+            }
+        )
+    elif "macosx" in platform:
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": repackage_task_ref},
+                "taskType": "repackage",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.dmg"],
+                "locale": partner_path,
+            }
+        )
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": repackage_signing_task_ref},
+                "taskType": "repackage",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.dmg.asc"],
+                "locale": partner_path,
+            }
+        )
+    elif "win" in platform:
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": repackage_signing_task_ref},
+                "taskType": "repackage",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.installer.exe"],
+                "locale": partner_path,
+            }
+        )
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": repackage_signing_task_ref},
+                "taskType": "repackage",
+                "paths": [f"{artifact_prefix}/{repack_id}/target.installer.exe.asc"],
+                "locale": partner_path,
+            }
+        )
+        if platform.startswith("win32") and repack_stub_installer:
+            upstream_artifacts.append(
+                {
+                    "taskId": {"task-reference": repackage_signing_task_ref},
+                    "taskType": "repackage",
+                    "paths": [
+                        "{}/{}/target.stub-installer.exe".format(
+                            artifact_prefix, repack_id
+                        )
+                    ],
+                    "locale": partner_path,
+                }
+            )
+            upstream_artifacts.append(
+                {
+                    "taskId": {"task-reference": repackage_signing_task_ref},
+                    "taskType": "repackage",
+                    "paths": [
+                        "{}/{}/target.stub-installer.exe.asc".format(
+                            artifact_prefix, repack_id
+                        )
+                    ],
+                    "locale": partner_path,
+                }
+            )
+
+    if not upstream_artifacts:
+        raise Exception("Couldn't find any upstream artifacts.")
+
+    return upstream_artifacts
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        platform = job["attributes"]["build_platform"]
+        repack_id = job["extra"]["repack_id"]
+        partner, subpartner, locale = job["extra"]["repack_id"].split("/")
+        partner_config = get_partner_config_by_kind(config, config.kind)
+        repack_stub_installer = partner_config[partner][subpartner].get(
+            "repack_stub_installer"
+        )
+        build_task = None
+        repackage_task = None
+        repackage_signing_task = None
+
+        for dependency in job["dependencies"].keys():
+            if "repackage-signing" in dependency:
+                repackage_signing_task = dependency
+            elif "repackage" in dependency:
+                repackage_task = dependency
+            else:
+                build_task = "build"
+
+        build_task_ref = "<" + str(build_task) + ">"
+        repackage_task_ref = "<" + str(repackage_task) + ">"
+        repackage_signing_task_ref = "<" + str(repackage_signing_task) + ">"
+
+        # generate the partner path; we'll send this to beetmover as the "locale"
+        ftp_platform = get_ftp_platform(platform)
+        repl_dict = {
+            "build_number": config.params["build_number"],
+            "locale": locale,
+            "partner": partner,
+            "platform": ftp_platform,
+            "release_partner_build_number": config.params[
+                "release_partner_build_number"
+            ],
+            "subpartner": subpartner,
+            "version": config.params["version"],
+        }
+        partner_public = job["partner_public"]
+        if partner_public:
+            partner_path_key = "partner-public-path"
+        else:
+            partner_path_key = "partner-private-path"
+        # Kinds can set these to None
+        if not job[partner_path_key]:
+            continue
+        partner_path = job[partner_path_key].format(**repl_dict)
+        del job["partner_public"]
+        del job["partner-private-path"]
+        del job["partner-public-path"]
+        del job["partner-bucket-scope"]
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_upstream_artifacts(
+                job,
+                build_task_ref,
+                repackage_task_ref,
+                repackage_signing_task_ref,
+                platform,
+                repack_id,
+                partner_path,
+                repack_stub_installer,
+            ),
+            "partner-public": partner_public,
+        }
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_snap.py b/taskcluster/gecko_taskgraph/transforms/beetmover_snap.py
new file mode 100644
index 0000000000..40f5132cc1
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_snap.py
@@ -0,0 +1,42 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the snap beetmover kind into an actual task description.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def leave_snap_repackage_dependencies_only(config, jobs):
+    for job in jobs:
+        # XXX: We delete the build dependency because, unlike the other beetmover
+        # tasks, source doesn't depend on any build task at all. This hack should
+        # go away when we rewrite beetmover transforms to allow more flexibility in deps
+
+        job["dependencies"] = {
+            key: value
+            for key, value in job["dependencies"].items()
+            if key == "release-snap-repackage"
+        }
+
+        job["worker"]["upstream-artifacts"] = [
+            upstream_artifact
+            for upstream_artifact in job["worker"]["upstream-artifacts"]
+            if upstream_artifact["taskId"]["task-reference"]
+            == "<release-snap-repackage>"
+        ]
+
+        yield job
+
+
+@transforms.add
+def set_custom_treeherder_job_name(config, jobs):
+    for job in jobs:
+        job.get("treeherder", {})["symbol"] = "Snap(BM)"
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_source.py b/taskcluster/gecko_taskgraph/transforms/beetmover_source.py
new file mode 100644
index 0000000000..573f684a98
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_source.py
@@ -0,0 +1,35 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover-source task to also append `build` as dependency
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def remove_build_dependency_in_beetmover_source(config, jobs):
+    for job in jobs:
+        # XXX: We delete the build dependency because, unlike the other beetmover
+        # tasks, source doesn't depend on any build task at all. This hack should
+        # go away when we rewrite beetmover transforms to allow more flexibility in deps
+        # Essentially, we should use multi_dep for beetmover.
+        for depname in job["dependencies"]:
+            if "signing" not in depname:
+                del job["dependencies"][depname]
+                break
+        else:
+            raise Exception("Can't find build dep in beetmover source!")
+
+        all_upstream_artifacts = job["worker"]["upstream-artifacts"]
+        upstream_artifacts_without_build = [
+            upstream_artifact
+            for upstream_artifact in all_upstream_artifacts
+            if upstream_artifact["taskId"]["task-reference"] != f"<{depname}>"
+        ]
+        job["worker"]["upstream-artifacts"] = upstream_artifacts_without_build
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/beetmover_source_checksums.py b/taskcluster/gecko_taskgraph/transforms/beetmover_source_checksums.py
new file mode 100644
index 0000000000..bcaa889903
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/beetmover_source_checksums.py
@@ -0,0 +1,137 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform release-beetmover-source-checksums into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+beetmover_checksums_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("locale"): str,
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_checksums_description_schema)
+
+
+@transforms.add
+def make_beetmover_checksums_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "BMcss(N)")
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+
+        label = job["label"]
+        build_platform = attributes.get("build_platform")
+
+        description = "Beetmover submission of checksums for source file"
+
+        extra = {}
+        if "devedition" in build_platform:
+            extra["product"] = "devedition"
+        else:
+            extra["product"] = "firefox"
+
+        dependencies = {dep_job.kind: dep_job.label}
+        for k, v in dep_job.dependencies.items():
+            if k.startswith("beetmover"):
+                dependencies[k] = v
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "extra": extra,
+        }
+
+        if "shipping-phase" in job:
+            task["shipping-phase"] = job["shipping-phase"]
+
+        if "shipping-product" in job:
+            task["shipping-product"] = job["shipping-product"]
+
+        yield task
+
+
+@transforms.add
+def make_beetmover_checksums_worker(config, jobs):
+    for job in jobs:
+        valid_beetmover_job = len(job["dependencies"]) == 2
+        if not valid_beetmover_job:
+            raise NotImplementedError("Beetmover checksums must have two dependencies.")
+
+        locale = job["attributes"].get("locale")
+        platform = job["attributes"]["build_platform"]
+
+        refs = {
+            "beetmover": None,
+            "signing": None,
+        }
+        for dependency in job["dependencies"].keys():
+            if dependency.startswith("beetmover"):
+                refs["beetmover"] = f"<{dependency}>"
+            else:
+                refs["signing"] = f"<{dependency}>"
+        if None in refs.values():
+            raise NotImplementedError(
+                "Beetmover checksums must have a beetmover and signing dependency!"
+            )
+
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform, locale
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform
+            ),
+        }
+
+        if locale:
+            worker["locale"] = locale
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/bootstrap.py b/taskcluster/gecko_taskgraph/transforms/bootstrap.py
new file mode 100644
index 0000000000..e4537cab01
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bootstrap.py
@@ -0,0 +1,132 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema
+from voluptuous import Any, Optional, Required
+
+transforms = TransformSequence()
+
+bootstrap_schema = Schema(
+    {
+        # Name of the bootstrap task.
+        Required("name"): str,
+        # Name of the docker image. Ideally, we'd also have tasks for mac and windows,
+        # but we unfortunately don't have workers barebones enough for such testing
+        # to be satisfactory.
+        Required("image"): Any(str, {"in-tree": str}),
+        # Initialization commands.
+        Required("pre-commands"): [str],
+        # relative path (from config.path) to the file task was defined in
+        Optional("job-from"): str,
+    }
+)
+
+
+transforms.add_validate(bootstrap_schema)
+
+
+@transforms.add
+def bootstrap_tasks(config, tasks):
+    for task in tasks:
+        name = task.pop("name")
+        image = task.pop("image")
+        pre_commands = task.pop("pre-commands")
+
+        head_repo = config.params["head_repository"]
+        head_rev = config.params["head_rev"]
+
+        # Get all the non macos/windows local toolchains (the only ones bootstrap can use),
+        # and use them as dependencies for the tasks we create, so that they don't start
+        # before any potential toolchain task that would be triggered on the same push
+        # (which would lead to bootstrap failing).
+        dependencies = {
+            name: name
+            for name, task in config.kind_dependencies_tasks.items()
+            if task.attributes.get("local-toolchain")
+            and not name.startswith(("toolchain-macos", "toolchain-win"))
+        }
+        # We don't test the artifacts variants, or js, because they are essentially subsets.
+        # Mobile and browser are different enough to warrant testing them separately.
+        for app in ("browser", "mobile_android"):
+            commands = pre_commands + [
+                # MOZ_AUTOMATION changes the behavior, and we want something closer to user
+                # machines.
+                "unset MOZ_AUTOMATION",
+                f"curl -O {head_repo}/raw-file/{head_rev}/python/mozboot/bin/bootstrap.py",
+                f"python3 bootstrap.py --no-interactive --application-choice {app}",
+                "cd mozilla-unified",
+                # After bootstrap, configure should go through without its own auto-bootstrap.
+                "./mach configure --disable-bootstrap",
+                # Then a build should go through too.
+                "./mach build",
+            ]
+
+            os_specific = []
+            if app == "mobile_android":
+                os_specific += ["android*"]
+            for os, filename in (
+                ("debian", "debian.py"),
+                ("ubuntu", "debian.py"),
+                ("fedora", "centosfedora.py"),
+                ("rockylinux", "centosfedora.py"),
+                ("opensuse", "opensuse.py"),
+                ("gentoo", "gentoo.py"),
+                ("archlinux", "archlinux.py"),
+                ("voidlinux", "void.py"),
+            ):
+                if name.startswith(os):
+                    os_specific.append(filename)
+                    break
+            else:
+                raise Exception(f"Missing OS specific bootstrap file for {name}")
+
+            taskdesc = {
+                "label": f"{config.kind}-{name}-{app}",
+                "description": f"Bootstrap {app} build on {name}",
+                "always-target": True,
+                "scopes": [],
+                "treeherder": {
+                    "symbol": f"Boot({name})",
+                    "platform": {
+                        "browser": "linux64/opt",
+                        "mobile_android": "android-5-0-armv7/opt",
+                    }[app],
+                    "kind": "other",
+                    "tier": 2,
+                },
+                "run-on-projects": ["trunk"],
+                "worker-type": "b-linux-gcp",
+                "worker": {
+                    "implementation": "docker-worker",
+                    "docker-image": image,
+                    "os": "linux",
+                    "env": {
+                        "GECKO_HEAD_REPOSITORY": head_repo,
+                        "GECKO_HEAD_REV": head_rev,
+                        "MACH_NO_TERMINAL_FOOTER": "1",
+                        "MOZ_SCM_LEVEL": config.params["level"],
+                    },
+                    "command": ["sh", "-c", "-x", "-e", " && ".join(commands)],
+                    "max-run-time": 7200,
+                },
+                "dependencies": dependencies,
+                "optimization": {
+                    "skip-unless-changed": [
+                        "python/mozboot/bin/bootstrap.py",
+                        "python/mozboot/mozboot/base.py",
+                        "python/mozboot/mozboot/bootstrap.py",
+                        "python/mozboot/mozboot/linux_common.py",
+                        "python/mozboot/mozboot/mach_commands.py",
+                        "python/mozboot/mozboot/mozconfig.py",
+                        "python/mozboot/mozboot/rust.py",
+                        "python/mozboot/mozboot/sccache.py",
+                        "python/mozboot/mozboot/util.py",
+                    ]
+                    + [f"python/mozboot/mozboot/{f}" for f in os_specific]
+                },
+            }
+
+            yield taskdesc
diff --git a/taskcluster/gecko_taskgraph/transforms/bouncer_aliases.py b/taskcluster/gecko_taskgraph/transforms/bouncer_aliases.py
new file mode 100644
index 0000000000..38f1aa136a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bouncer_aliases.py
@@ -0,0 +1,108 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add from parameters.yml into bouncer submission tasks.
+"""
+
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.transforms.bouncer_submission import craft_bouncer_product_name
+from gecko_taskgraph.transforms.bouncer_submission_partners import (
+    craft_partner_bouncer_product_name,
+)
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.partners import get_partners_to_be_published
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        resolve_keyed_by(
+            job,
+            "scopes",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        resolve_keyed_by(
+            job,
+            "bouncer-products-per-alias",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]},
+        )
+        if "partner-bouncer-products-per-alias" in job:
+            resolve_keyed_by(
+                job,
+                "partner-bouncer-products-per-alias",
+                item_name=job["name"],
+                **{"release-type": config.params["release_type"]},
+            )
+
+        job["worker"]["entries"] = craft_bouncer_entries(config, job)
+
+        del job["bouncer-products-per-alias"]
+        if "partner-bouncer-products-per-alias" in job:
+            del job["partner-bouncer-products-per-alias"]
+
+        if job["worker"]["entries"]:
+            yield job
+        else:
+            logger.warn(
+                'No bouncer entries defined in bouncer submission task for "{}". \
+Job deleted.'.format(
+                    job["name"]
+                )
+            )
+
+
+def craft_bouncer_entries(config, job):
+    release_config = get_release_config(config)
+
+    product = job["shipping-product"]
+    current_version = release_config["version"]
+    bouncer_products_per_alias = job["bouncer-products-per-alias"]
+
+    entries = {
+        bouncer_alias: craft_bouncer_product_name(
+            product,
+            bouncer_product,
+            current_version,
+        )
+        for bouncer_alias, bouncer_product in bouncer_products_per_alias.items()
+    }
+
+    partner_bouncer_products_per_alias = job.get("partner-bouncer-products-per-alias")
+    if partner_bouncer_products_per_alias:
+        partners = get_partners_to_be_published(config)
+        for partner, sub_config_name, _ in partners:
+            entries.update(
+                {
+                    bouncer_alias.replace(
+                        "PARTNER", f"{partner}-{sub_config_name}"
+                    ): craft_partner_bouncer_product_name(
+                        product,
+                        bouncer_product,
+                        current_version,
+                        partner,
+                        sub_config_name,
+                    )
+                    for bouncer_alias, bouncer_product in partner_bouncer_products_per_alias.items()  # NOQA: E501
+                }
+            )
+
+    return entries
diff --git a/taskcluster/gecko_taskgraph/transforms/bouncer_check.py b/taskcluster/gecko_taskgraph/transforms/bouncer_check.py
new file mode 100644
index 0000000000..9261ef9463
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bouncer_check.py
@@ -0,0 +1,111 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import json
+import logging
+from pipes import quote as shell_quote
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_command(config, jobs):
+    for job in jobs:
+        command = [
+            "python",
+            "testing/mozharness/scripts/release/bouncer_check.py",
+        ]
+        job["run"].update(
+            {
+                "using": "mach",
+                "mach": command,
+            }
+        )
+        yield job
+
+
+@transforms.add
+def add_previous_versions(config, jobs):
+    release_config = get_release_config(config)
+    if not release_config.get("partial_versions"):
+        for job in jobs:
+            yield job
+    else:
+        extra_params = []
+        for partial in release_config["partial_versions"].split(","):
+            extra_params.append(
+                "--previous-version={}".format(partial.split("build")[0].strip())
+            )
+
+        for job in jobs:
+            job["run"]["mach"].extend(extra_params)
+            yield job
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by project, etc."""
+    fields = [
+        "run.config",
+        "run.product-field",
+        "run.extra-config",
+    ]
+
+    release_config = get_release_config(config)
+    version = release_config["version"]
+
+    for job in jobs:
+        for field in fields:
+            resolve_keyed_by(
+                item=job,
+                field=field,
+                item_name=job["name"],
+                **{
+                    "project": config.params["project"],
+                    "release-level": release_level(config.params["project"]),
+                    "release-type": config.params["release_type"],
+                },
+            )
+
+        for cfg in job["run"]["config"]:
+            job["run"]["mach"].extend(["--config", cfg])
+
+        if config.kind == "cron-bouncer-check":
+            job["run"]["mach"].extend(
+                [
+                    "--product-field={}".format(job["run"]["product-field"]),
+                    "--products-url={}".format(job["run"]["products-url"]),
+                ]
+            )
+            del job["run"]["product-field"]
+            del job["run"]["products-url"]
+        elif config.kind == "release-bouncer-check":
+            job["run"]["mach"].append(f"--version={version}")
+
+        del job["run"]["config"]
+
+        if "extra-config" in job["run"]:
+            env = job["worker"].setdefault("env", {})
+            env["EXTRA_MOZHARNESS_CONFIG"] = json.dumps(
+                job["run"]["extra-config"], sort_keys=True
+            )
+            del job["run"]["extra-config"]
+
+        yield job
+
+
+@transforms.add
+def command_to_string(config, jobs):
+    """Convert command to string to make it work properly with run-task"""
+    for job in jobs:
+        job["run"]["mach"] = " ".join(map(shell_quote, job["run"]["mach"]))
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/bouncer_locations.py b/taskcluster/gecko_taskgraph/transforms/bouncer_locations.py
new file mode 100644
index 0000000000..e755b73c27
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bouncer_locations.py
@@ -0,0 +1,35 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+logger = logging.getLogger(__name__)
+
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job, "worker-type", item_name=job["name"], project=config.params["project"]
+        )
+        resolve_keyed_by(
+            job, "scopes", item_name=job["name"], project=config.params["project"]
+        )
+        resolve_keyed_by(
+            job,
+            "bouncer-products",
+            item_name=job["name"],
+            project=config.params["project"],
+        )
+
+        job["worker"]["bouncer-products"] = job["bouncer-products"]
+
+        del job["bouncer-products"]
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/bouncer_submission.py b/taskcluster/gecko_taskgraph/transforms/bouncer_submission.py
new file mode 100644
index 0000000000..d6320a9312
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bouncer_submission.py
@@ -0,0 +1,335 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add from parameters.yml into bouncer submission tasks.
+"""
+
+
+import copy
+import logging
+
+import attr
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.transforms.l10n import parse_locales_file
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+logger = logging.getLogger(__name__)
+
+
+FTP_PLATFORMS_PER_BOUNCER_PLATFORM = {
+    "linux": "linux-i686",
+    "linux64": "linux-x86_64",
+    "osx": "mac",
+    "win": "win32",
+    "win64": "win64",
+    "win64-aarch64": "win64-aarch64",
+}
+
+# :lang is interpolated by bouncer at runtime
+CANDIDATES_PATH_TEMPLATE = "/{ftp_product}/candidates/{version}-candidates/build{build_number}/\
+{update_folder}{ftp_platform}/:lang/{file}"
+RELEASES_PATH_TEMPLATE = "/{ftp_product}/releases/{version}/\
+{update_folder}{ftp_platform}/:lang/{file}"
+
+
+CONFIG_PER_BOUNCER_PRODUCT = {
+    "complete-mar": {
+        "name_postfix": "-Complete",
+        "path_template": RELEASES_PATH_TEMPLATE,
+        "file_names": {
+            "default": "{product}-{version}.complete.mar",
+        },
+    },
+    "complete-mar-candidates": {
+        "name_postfix": "build{build_number}-Complete",
+        "path_template": CANDIDATES_PATH_TEMPLATE,
+        "file_names": {
+            "default": "{product}-{version}.complete.mar",
+        },
+    },
+    "installer": {
+        "path_template": RELEASES_PATH_TEMPLATE,
+        "file_names": {
+            "linux": "{product}-{version}.tar.bz2",
+            "linux64": "{product}-{version}.tar.bz2",
+            "osx": "{pretty_product}%20{version}.dmg",
+            "win": "{pretty_product}%20Setup%20{version}.exe",
+            "win64": "{pretty_product}%20Setup%20{version}.exe",
+            "win64-aarch64": "{pretty_product}%20Setup%20{version}.exe",
+        },
+    },
+    "partial-mar": {
+        "name_postfix": "-Partial-{previous_version}",
+        "path_template": RELEASES_PATH_TEMPLATE,
+        "file_names": {
+            "default": "{product}-{previous_version}-{version}.partial.mar",
+        },
+    },
+    "partial-mar-candidates": {
+        "name_postfix": "build{build_number}-Partial-{previous_version}build{previous_build}",
+        "path_template": CANDIDATES_PATH_TEMPLATE,
+        "file_names": {
+            "default": "{product}-{previous_version}-{version}.partial.mar",
+        },
+    },
+    "stub-installer": {
+        "name_postfix": "-stub",
+        # We currently have a sole win32 stub installer that is to be used
+        # in all windows platforms to toggle between full installers
+        "path_template": RELEASES_PATH_TEMPLATE.replace("{ftp_platform}", "win32"),
+        "file_names": {
+            "win": "{pretty_product}%20Installer.exe",
+            "win64": "{pretty_product}%20Installer.exe",
+            "win64-aarch64": "{pretty_product}%20Installer.exe",
+        },
+    },
+    "msi": {
+        "name_postfix": "-msi-SSL",
+        "path_template": RELEASES_PATH_TEMPLATE,
+        "file_names": {
+            "win": "{pretty_product}%20Setup%20{version}.msi",
+            "win64": "{pretty_product}%20Setup%20{version}.msi",
+        },
+    },
+    "msix": {
+        "name_postfix": "-msix-SSL",
+        "path_template": RELEASES_PATH_TEMPLATE.replace(":lang", "multi"),
+        "file_names": {
+            "win": "{pretty_product}%20Setup%20{version}.msix",
+            "win64": "{pretty_product}%20Setup%20{version}.msix",
+        },
+    },
+    "pkg": {
+        "name_postfix": "-pkg-SSL",
+        "path_template": RELEASES_PATH_TEMPLATE,
+        "file_names": {
+            "osx": "{pretty_product}%20{version}.pkg",
+        },
+    },
+    "langpack": {
+        "name_postfix": "-langpack-SSL",
+        "path_template": RELEASES_PATH_TEMPLATE.replace(":lang", "xpi"),
+        "file_names": {"default": ":lang.xpi"},
+    },
+}
+CONFIG_PER_BOUNCER_PRODUCT["installer-ssl"] = copy.deepcopy(
+    CONFIG_PER_BOUNCER_PRODUCT["installer"]
+)
+CONFIG_PER_BOUNCER_PRODUCT["installer-ssl"]["name_postfix"] = "-SSL"
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+        resolve_keyed_by(
+            job,
+            "scopes",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+        resolve_keyed_by(
+            job,
+            "bouncer-products",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]}
+        )
+
+        # No need to filter out ja-JP-mac, we need to upload both; but we do
+        # need to filter out the platforms they come with
+        all_locales = sorted(
+            locale
+            for locale in parse_locales_file(job["locales-file"]).keys()
+            if locale not in ("linux", "win32", "osx")
+        )
+
+        job["worker"]["locales"] = all_locales
+        job["worker"]["entries"] = craft_bouncer_entries(config, job)
+
+        del job["locales-file"]
+        del job["bouncer-platforms"]
+        del job["bouncer-products"]
+
+        if job["worker"]["entries"]:
+            yield job
+        else:
+            logger.warn(
+                'No bouncer entries defined in bouncer submission task for "{}". \
+Job deleted.'.format(
+                    job["name"]
+                )
+            )
+
+
+def craft_bouncer_entries(config, job):
+    release_config = get_release_config(config)
+
+    product = job["shipping-product"]
+    bouncer_platforms = job["bouncer-platforms"]
+
+    current_version = release_config["version"]
+    current_build_number = release_config["build_number"]
+
+    bouncer_products = job["bouncer-products"]
+    previous_versions_string = release_config.get("partial_versions", None)
+    if previous_versions_string:
+        previous_versions = previous_versions_string.split(", ")
+    else:
+        logger.warn(
+            'No partials defined! Bouncer submission task won\'t send any \
+partial-related entry for "{}"'.format(
+                job["name"]
+            )
+        )
+        bouncer_products = [
+            bouncer_product
+            for bouncer_product in bouncer_products
+            if "partial" not in bouncer_product
+        ]
+        previous_versions = [None]
+
+    project = config.params["project"]
+
+    return {
+        craft_bouncer_product_name(
+            product,
+            bouncer_product,
+            current_version,
+            current_build_number,
+            previous_version,
+        ): {
+            "options": {
+                "add_locales": False if "msix" in bouncer_product else True,
+                "ssl_only": craft_ssl_only(bouncer_product, project),
+            },
+            "paths_per_bouncer_platform": craft_paths_per_bouncer_platform(
+                product,
+                bouncer_product,
+                bouncer_platforms,
+                current_version,
+                current_build_number,
+                previous_version,
+            ),
+        }
+        for bouncer_product in bouncer_products
+        for previous_version in previous_versions
+    }
+
+
+def craft_paths_per_bouncer_platform(
+    product,
+    bouncer_product,
+    bouncer_platforms,
+    current_version,
+    current_build_number,
+    previous_version=None,
+):
+    paths_per_bouncer_platform = {}
+    for bouncer_platform in bouncer_platforms:
+        file_names_per_platform = CONFIG_PER_BOUNCER_PRODUCT[bouncer_product][
+            "file_names"
+        ]
+        file_name_template = file_names_per_platform.get(
+            bouncer_platform, file_names_per_platform.get("default", None)
+        )
+        if not file_name_template:
+            # Some bouncer product like stub-installer are only meant to be on Windows.
+            # Thus no default value is defined there
+            continue
+
+        file_name_product = _craft_filename_product(product)
+        file_name = file_name_template.format(
+            product=file_name_product,
+            pretty_product=file_name_product.capitalize(),
+            version=current_version,
+            previous_version=split_build_data(previous_version)[0],
+        )
+
+        path_template = CONFIG_PER_BOUNCER_PRODUCT[bouncer_product]["path_template"]
+        file_relative_location = path_template.format(
+            ftp_product=_craft_ftp_product(product),
+            version=current_version,
+            build_number=current_build_number,
+            update_folder="update/" if "-mar" in bouncer_product else "",
+            ftp_platform=FTP_PLATFORMS_PER_BOUNCER_PLATFORM[bouncer_platform],
+            file=file_name,
+        )
+
+        paths_per_bouncer_platform[bouncer_platform] = file_relative_location
+
+    return paths_per_bouncer_platform
+
+
+def _craft_ftp_product(product):
+    return product.lower()
+
+
+def _craft_filename_product(product):
+    return "firefox" if product == "devedition" else product
+
+
+@attr.s
+class InvalidSubstitution:
+    error = attr.ib(type=str)
+
+    def __str__(self):
+        raise Exception("Partial is being processed, but no previous version defined.")
+
+
+def craft_bouncer_product_name(
+    product,
+    bouncer_product,
+    current_version,
+    current_build_number=None,
+    previous_version=None,
+):
+    if previous_version is None:
+        previous_version = previous_build = InvalidSubstitution(
+            "Partial is being processed, but no previous version defined."
+        )
+    else:
+        previous_version, previous_build = split_build_data(previous_version)
+    postfix = (
+        CONFIG_PER_BOUNCER_PRODUCT[bouncer_product]
+        .get("name_postfix", "")
+        .format(
+            build_number=current_build_number,
+            previous_version=previous_version,
+            previous_build=previous_build,
+        )
+    )
+
+    return "{product}-{version}{postfix}".format(
+        product=product.capitalize(), version=current_version, postfix=postfix
+    )
+
+
+def craft_ssl_only(bouncer_product, project):
+    # XXX ESR is the only channel where we force serve the installer over SSL
+    if "-esr" in project and bouncer_product == "installer":
+        return True
+
+    return bouncer_product not in (
+        "complete-mar",
+        "complete-mar-candidates",
+        "installer",
+        "partial-mar",
+        "partial-mar-candidates",
+    )
+
+
+def split_build_data(version):
+    if version and "build" in version:
+        return version.split("build")
+    return version, InvalidSubstitution("k")
diff --git a/taskcluster/gecko_taskgraph/transforms/bouncer_submission_partners.py b/taskcluster/gecko_taskgraph/transforms/bouncer_submission_partners.py
new file mode 100644
index 0000000000..0f298cb120
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/bouncer_submission_partners.py
@@ -0,0 +1,193 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add from parameters.yml into bouncer submission tasks.
+"""
+
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.transforms.bouncer_submission import (
+    CONFIG_PER_BOUNCER_PRODUCT as CONFIG_PER_BOUNCER_PRODUCT_VANILLA,
+)
+from gecko_taskgraph.transforms.bouncer_submission import (
+    FTP_PLATFORMS_PER_BOUNCER_PLATFORM,
+    _craft_filename_product,
+    _craft_ftp_product,
+)
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.partners import (
+    check_if_partners_enabled,
+    get_partners_to_be_published,
+)
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+logger = logging.getLogger(__name__)
+
+
+PARTNER_PLATFORMS_TO_BOUNCER = {
+    "linux-shippable": "linux",
+    "linux64-shippable": "linux64",
+    "macosx64-shippable": "osx",
+    "win32-shippable": "win",
+    "win64-shippable": "win64",
+    "win64-aarch64-shippable": "win64-aarch64",
+}
+
+# :lang is interpolated by bouncer at runtime
+RELEASES_PARTNERS_PATH_TEMPLATE = "/{ftp_product}/releases/partners/{partner}/{sub_config}/\
+{version}/{ftp_platform}/:lang/{file}"
+
+CONFIG_PER_BOUNCER_PRODUCT = {
+    "installer": {
+        "name_postfix": "-{partner}-{sub_config}",
+        "path_template": RELEASES_PARTNERS_PATH_TEMPLATE,
+        "file_names": CONFIG_PER_BOUNCER_PRODUCT_VANILLA["installer"]["file_names"],
+    },
+    "stub-installer": {
+        "name_postfix": "-{partner}-{sub_config}-stub",
+        # We currently have a sole win32 stub installer that is to be used
+        # in all windows platforms to toggle between full installers
+        "path_template": RELEASES_PARTNERS_PATH_TEMPLATE.replace(
+            "{ftp_platform}", "win32"
+        ),
+        "file_names": CONFIG_PER_BOUNCER_PRODUCT_VANILLA["stub-installer"][
+            "file_names"
+        ],
+    },
+}
+
+transforms = TransformSequence()
+transforms.add(check_if_partners_enabled)
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+        resolve_keyed_by(
+            job,
+            "scopes",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+        resolve_keyed_by(
+            job,
+            "bouncer-products",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]}
+        )
+
+        # the schema requires at least one locale but this will not be used
+        job["worker"]["locales"] = ["fake"]
+        job["worker"]["entries"] = craft_bouncer_entries(config, job)
+
+        del job["locales-file"]
+        del job["bouncer-platforms"]
+        del job["bouncer-products"]
+
+        if job["worker"]["entries"]:
+            yield job
+
+
+def craft_bouncer_entries(config, job):
+    release_config = get_release_config(config)
+
+    product = job["shipping-product"]
+    current_version = release_config["version"]
+    bouncer_products = job["bouncer-products"]
+
+    partners = get_partners_to_be_published(config)
+    entries = {}
+    for partner, sub_config_name, platforms in partners:
+        platforms = [PARTNER_PLATFORMS_TO_BOUNCER[p] for p in platforms]
+        entries.update(
+            {
+                craft_partner_bouncer_product_name(
+                    product, bouncer_product, current_version, partner, sub_config_name
+                ): {
+                    "options": {
+                        "add_locales": False,  # partners may use different sets of locales
+                        "ssl_only": craft_ssl_only(bouncer_product),
+                    },
+                    "paths_per_bouncer_platform": craft_paths_per_bouncer_platform(
+                        product,
+                        bouncer_product,
+                        platforms,
+                        current_version,
+                        partner,
+                        sub_config_name,
+                    ),
+                }
+                for bouncer_product in bouncer_products
+            }
+        )
+    return entries
+
+
+def craft_paths_per_bouncer_platform(
+    product, bouncer_product, bouncer_platforms, current_version, partner, sub_config
+):
+    paths_per_bouncer_platform = {}
+    for bouncer_platform in bouncer_platforms:
+        file_names_per_platform = CONFIG_PER_BOUNCER_PRODUCT[bouncer_product][
+            "file_names"
+        ]
+        file_name_template = file_names_per_platform.get(
+            bouncer_platform, file_names_per_platform.get("default", None)
+        )
+        if not file_name_template:
+            # Some bouncer product like stub-installer are only meant to be on Windows.
+            # Thus no default value is defined there
+            continue
+
+        file_name_product = _craft_filename_product(product)
+        file_name = file_name_template.format(
+            product=file_name_product,
+            pretty_product=file_name_product.capitalize(),
+            version=current_version,
+        )
+
+        path_template = CONFIG_PER_BOUNCER_PRODUCT[bouncer_product]["path_template"]
+        file_relative_location = path_template.format(
+            ftp_product=_craft_ftp_product(product),
+            version=current_version,
+            ftp_platform=FTP_PLATFORMS_PER_BOUNCER_PLATFORM[bouncer_platform],
+            partner=partner,
+            sub_config=sub_config,
+            file=file_name,
+        )
+
+        paths_per_bouncer_platform[bouncer_platform] = file_relative_location
+
+    return paths_per_bouncer_platform
+
+
+def craft_partner_bouncer_product_name(
+    product, bouncer_product, current_version, partner, sub_config
+):
+    postfix = (
+        CONFIG_PER_BOUNCER_PRODUCT[bouncer_product]
+        .get("name_postfix", "")
+        .format(
+            partner=partner,
+            sub_config=sub_config,
+        )
+    )
+
+    return "{product}-{version}{postfix}".format(
+        product=product.capitalize(), version=current_version, postfix=postfix
+    )
+
+
+def craft_ssl_only(bouncer_product):
+    return bouncer_product == "stub-installer"
diff --git a/taskcluster/gecko_taskgraph/transforms/build.py b/taskcluster/gecko_taskgraph/transforms/build.py
new file mode 100644
index 0000000000..94a4d71b0b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/build.py
@@ -0,0 +1,238 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Apply some defaults and minor modifications to the jobs defined in the build
+kind.
+"""
+import logging
+
+from mozbuild.artifact_builds import JOB_CHOICES as ARTIFACT_JOBS
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+from taskgraph.util.treeherder import add_suffix
+
+from gecko_taskgraph.util.attributes import RELEASE_PROJECTS, is_try, release_level
+from gecko_taskgraph.util.workertypes import worker_type_implementation
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_defaults(config, jobs):
+    """Set defaults, including those that differ per worker implementation"""
+    for job in jobs:
+        job["treeherder"].setdefault("kind", "build")
+        job["treeherder"].setdefault("tier", 1)
+        _, worker_os = worker_type_implementation(
+            config.graph_config, config.params, job["worker-type"]
+        )
+        worker = job.setdefault("worker", {})
+        worker.setdefault("env", {})
+        worker["chain-of-trust"] = True
+        if worker_os == "linux":
+            worker.setdefault("docker-image", {"in-tree": "debian11-amd64-build"})
+
+        yield job
+
+
+@transforms.add
+def stub_installer(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "stub-installer",
+            item_name=job["name"],
+            project=config.params["project"],
+            **{
+                "release-type": config.params["release_type"],
+            },
+        )
+        job.setdefault("attributes", {})
+        if job.get("stub-installer"):
+            job["attributes"]["stub-installer"] = job["stub-installer"]
+            job["worker"]["env"].update({"USE_STUB_INSTALLER": "1"})
+        if "stub-installer" in job:
+            del job["stub-installer"]
+        yield job
+
+
+@transforms.add
+def resolve_shipping_product(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "shipping-product",
+            item_name=job["name"],
+            **{
+                "release-type": config.params["release_type"],
+            },
+        )
+        yield job
+
+
+@transforms.add
+def update_channel(config, jobs):
+    keys = [
+        "run.update-channel",
+        "run.mar-channel-id",
+        "run.accepted-mar-channel-ids",
+    ]
+    for job in jobs:
+        job["worker"].setdefault("env", {})
+        for key in keys:
+            resolve_keyed_by(
+                job,
+                key,
+                item_name=job["name"],
+                **{
+                    "project": config.params["project"],
+                    "release-type": config.params["release_type"],
+                },
+            )
+        update_channel = job["run"].pop("update-channel", None)
+        if update_channel:
+            job["run"].setdefault("extra-config", {})["update_channel"] = update_channel
+            job["attributes"]["update-channel"] = update_channel
+        mar_channel_id = job["run"].pop("mar-channel-id", None)
+        if mar_channel_id:
+            job["attributes"]["mar-channel-id"] = mar_channel_id
+            job["worker"]["env"]["MAR_CHANNEL_ID"] = mar_channel_id
+        accepted_mar_channel_ids = job["run"].pop("accepted-mar-channel-ids", None)
+        if accepted_mar_channel_ids:
+            job["attributes"]["accepted-mar-channel-ids"] = accepted_mar_channel_ids
+            job["worker"]["env"]["ACCEPTED_MAR_CHANNEL_IDS"] = accepted_mar_channel_ids
+
+        yield job
+
+
+@transforms.add
+def mozconfig(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "run.mozconfig-variant",
+            item_name=job["name"],
+            **{
+                "release-type": config.params["release_type"],
+            },
+        )
+        mozconfig_variant = job["run"].pop("mozconfig-variant", None)
+        if mozconfig_variant:
+            job["run"].setdefault("extra-config", {})[
+                "mozconfig_variant"
+            ] = mozconfig_variant
+        yield job
+
+
+@transforms.add
+def use_artifact(config, jobs):
+    if is_try(config.params):
+        use_artifact = config.params["try_task_config"].get(
+            "use-artifact-builds", False
+        )
+    else:
+        use_artifact = False
+    for job in jobs:
+        if (
+            config.kind == "build"
+            and use_artifact
+            and job.get("index", {}).get("job-name") in ARTIFACT_JOBS
+            # If tests aren't packaged, then we are not able to rebuild all the packages
+            and job["worker"]["env"].get("MOZ_AUTOMATION_PACKAGE_TESTS") == "1"
+        ):
+            job["treeherder"]["symbol"] = add_suffix(job["treeherder"]["symbol"], "a")
+            job["worker"]["env"]["USE_ARTIFACT"] = "1"
+            job["attributes"]["artifact-build"] = True
+        yield job
+
+
+@transforms.add
+def use_profile_data(config, jobs):
+    for job in jobs:
+        use_pgo = job.pop("use-pgo", False)
+        disable_pgo = config.params["try_task_config"].get("disable-pgo", False)
+        artifact_build = job["attributes"].get("artifact-build")
+        if not use_pgo or disable_pgo or artifact_build:
+            yield job
+            continue
+
+        # If use_pgo is True, the task uses the generate-profile task of the
+        # same name. Otherwise a task can specify a specific generate-profile
+        # task to use in the use_pgo field.
+        if use_pgo is True:
+            name = job["name"]
+        else:
+            name = use_pgo
+        dependencies = f"generate-profile-{name}"
+        job.setdefault("dependencies", {})["generate-profile"] = dependencies
+        job.setdefault("fetches", {})["generate-profile"] = ["profdata.tar.xz"]
+        job["worker"]["env"].update({"TASKCLUSTER_PGO_PROFILE_USE": "1"})
+
+        _, worker_os = worker_type_implementation(
+            config.graph_config, config.params, job["worker-type"]
+        )
+        if worker_os == "linux":
+            # LTO linkage needs more open files than the default from run-task.
+            job["worker"]["env"].update({"MOZ_LIMIT_NOFILE": "8192"})
+
+        if job.get("use-sccache"):
+            raise Exception(
+                "use-sccache is incompatible with use-pgo in {}".format(job["name"])
+            )
+
+        yield job
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "use-sccache",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        yield job
+
+
+@transforms.add
+def enable_full_crashsymbols(config, jobs):
+    """Enable full crashsymbols on jobs with
+    'enable-full-crashsymbols' set to True and on release branches, or
+    on try"""
+    branches = RELEASE_PROJECTS | {
+        "toolchains",
+        "try",
+    }
+    for job in jobs:
+        enable_full_crashsymbols = job["attributes"].get("enable-full-crashsymbols")
+        if enable_full_crashsymbols and config.params["project"] in branches:
+            logger.debug("Enabling full symbol generation for %s", job["name"])
+            job["worker"]["env"]["MOZ_ENABLE_FULL_SYMBOLS"] = "1"
+        else:
+            logger.debug("Disabling full symbol generation for %s", job["name"])
+            job["attributes"].pop("enable-full-crashsymbols", None)
+        yield job
+
+
+@transforms.add
+def set_expiry(config, jobs):
+    for job in jobs:
+        attributes = job["attributes"]
+        if (
+            "shippable" in attributes
+            and attributes["shippable"]
+            and config.kind
+            in {
+                "build",
+            }
+        ):
+            expiration_policy = "long"
+        else:
+            expiration_policy = "medium"
+
+        job["expiration-policy"] = expiration_policy
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/build_attrs.py b/taskcluster/gecko_taskgraph/transforms/build_attrs.py
new file mode 100644
index 0000000000..9cda71718a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/build_attrs.py
@@ -0,0 +1,50 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.platforms import platform_family
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_build_attributes(config, jobs):
+    """
+    Set the build_platform and build_type attributes based on the job name.
+    Although not all jobs using this transform are actual "builds", the try
+    option syntax treats them as such, and this arranges the attributes
+    appropriately for that purpose.
+    """
+    for job in jobs:
+        build_platform, build_type = job["name"].split("/")
+
+        # pgo builds are represented as a different platform, type opt
+        if build_type == "pgo":
+            build_platform = build_platform + "-pgo"
+            build_type = "opt"
+
+        attributes = job.setdefault("attributes", {})
+        attributes.update(
+            {
+                "build_platform": build_platform,
+                "build_type": build_type,
+            }
+        )
+
+        yield job
+
+
+@transforms.add
+def set_schedules_optimization(config, jobs):
+    """Set the `skip-unless-affected` optimization based on the build platform."""
+    for job in jobs:
+        # don't add skip-unless-schedules if there's already a when defined
+        if "when" in job:
+            yield job
+            continue
+
+        build_platform = job["attributes"]["build_platform"]
+        job.setdefault("optimization", {"build": [platform_family(build_platform)]})
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/build_fat_aar.py b/taskcluster/gecko_taskgraph/transforms/build_fat_aar.py
new file mode 100644
index 0000000000..61df2111d2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/build_fat_aar.py
@@ -0,0 +1,78 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import copy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_prefix
+
+from gecko_taskgraph.util.declarative_artifacts import get_geckoview_upstream_artifacts
+
+transforms = TransformSequence()
+
+
+MOZ_ANDROID_FAT_AAR_ENV_MAP = {
+    "android-arm-shippable": "MOZ_ANDROID_FAT_AAR_ARMEABI_V7A",
+    "android-arm-shippable-lite": "MOZ_ANDROID_FAT_AAR_ARMEABI_V7A",
+    "android-aarch64-shippable": "MOZ_ANDROID_FAT_AAR_ARM64_V8A",
+    "android-aarch64-shippable-lite": "MOZ_ANDROID_FAT_AAR_ARM64_V8A",
+    "android-x86-shippable": "MOZ_ANDROID_FAT_AAR_X86",
+    "android-x86-shippable-lite": "MOZ_ANDROID_FAT_AAR_X86",
+    "android-x86_64-shippable": "MOZ_ANDROID_FAT_AAR_X86_64",
+    "android-x86_64-shippable-lite": "MOZ_ANDROID_FAT_AAR_X86_64",
+    "android-arm-opt": "MOZ_ANDROID_FAT_AAR_ARMEABI_V7A",
+    "android-aarch64-opt": "MOZ_ANDROID_FAT_AAR_ARM64_V8A",
+    "android-x86-opt": "MOZ_ANDROID_FAT_AAR_X86",
+    "android-x86_64-opt": "MOZ_ANDROID_FAT_AAR_X86_64",
+}
+
+
+@transforms.add
+def set_fetches_and_locations(config, jobs):
+    """Set defaults, including those that differ per worker implementation"""
+    for job in jobs:
+        dependencies = copy.deepcopy(job["dependencies"])
+
+        for platform, label in dependencies.items():
+            job["dependencies"] = {"build": label}
+
+            aar_location = _get_aar_location(config, job, platform)
+            prefix = get_artifact_prefix(job)
+            if not prefix.endswith("/"):
+                prefix = prefix + "/"
+            if aar_location.startswith(prefix):
+                aar_location = aar_location[len(prefix) :]
+
+            job.setdefault("fetches", {}).setdefault(platform, []).append(
+                {
+                    "artifact": aar_location,
+                    "extract": False,
+                }
+            )
+
+            aar_file_name = aar_location.split("/")[-1]
+            env_var = MOZ_ANDROID_FAT_AAR_ENV_MAP[platform]
+            job["worker"]["env"][env_var] = aar_file_name
+
+        job["dependencies"] = dependencies
+
+        yield job
+
+
+def _get_aar_location(config, job, platform):
+    artifacts_locations = []
+
+    for package in job["attributes"]["maven_packages"]:
+        artifacts_locations += get_geckoview_upstream_artifacts(
+            config, job, package, platform=platform
+        )
+
+    aar_locations = [
+        path for path in artifacts_locations[0]["paths"] if path.endswith(".aar")
+    ]
+    if len(aar_locations) != 1:
+        raise ValueError(f"Only a single AAR must be given. Got: {aar_locations}")
+
+    return aar_locations[0]
diff --git a/taskcluster/gecko_taskgraph/transforms/build_lints.py b/taskcluster/gecko_taskgraph/transforms/build_lints.py
new file mode 100644
index 0000000000..d1bd276059
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/build_lints.py
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Apply some defaults and minor modifications to the jobs defined in the build
+kind.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def check_mozharness_perfherder_options(config, jobs):
+    """Verify that multiple jobs don't use the same perfherder bucket.
+
+    Build jobs record perfherder metrics by default. Perfherder metrics go
+    to a bucket derived by the platform by default. The name can further be
+    customized by the presence of "extra options" either defined in
+    mozharness sub-configs or in an environment variable.
+
+    This linter tries to verify that no 2 jobs will send Perfherder metrics
+    to the same bucket by looking for jobs not defining extra options when
+    their platform or mozharness config are otherwise similar.
+    """
+
+    SEEN_CONFIGS = {}
+
+    for job in jobs:
+        if job["run"]["using"] != "mozharness":
+            yield job
+            continue
+
+        worker = job.get("worker", {})
+
+        platform = job["treeherder"]["platform"]
+        primary_config = job["run"]["config"][0]
+        options = worker.get("env", {}).get("PERFHERDER_EXTRA_OPTIONS")
+        shippable = job.get("attributes", {}).get("shippable", False)
+
+        # This isn't strictly necessary. But the Perfherder code looking at the
+        # values we care about is only active on builds. So it doesn't make
+        # sense to run this linter elsewhere.
+        assert primary_config.startswith("builds/")
+
+        key = (platform, primary_config, shippable, options)
+
+        if key in SEEN_CONFIGS:
+            raise Exception(
+                "Non-unique Perfherder data collection for jobs %s-%s and %s: "
+                "set PERFHERDER_EXTRA_OPTIONS in worker environment variables "
+                "or use different mozconfigs"
+                % (config.kind, job["name"], SEEN_CONFIGS[key])
+            )
+
+        SEEN_CONFIGS[key] = "{}-{}".format(config.kind, job["name"])
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/build_signing.py b/taskcluster/gecko_taskgraph/transforms/build_signing.py
new file mode 100644
index 0000000000..36f39f0b56
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/build_signing.py
@@ -0,0 +1,71 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the signing task into an actual task description.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.signed_artifacts import (
+    generate_specifications_of_artifacts_to_sign,
+)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_signed_routes(config, jobs):
+    """Add routes corresponding to the routes of the build task
+    this corresponds to, with .signed inserted, for all gecko.v2 routes"""
+
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        enable_signing_routes = job.pop("enable-signing-routes", True)
+
+        job["routes"] = []
+        if dep_job.attributes.get("shippable") and enable_signing_routes:
+            for dep_route in dep_job.task.get("routes", []):
+                if not dep_route.startswith("index.gecko.v2"):
+                    continue
+                branch = dep_route.split(".")[3]
+                rest = ".".join(dep_route.split(".")[4:])
+                job["routes"].append(f"index.gecko.v2.{branch}.signed.{rest}")
+
+        yield job
+
+
+@transforms.add
+def define_upstream_artifacts(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        upstream_artifact_task = job.pop("upstream-artifact-task", dep_job)
+
+        job["attributes"] = copy_attributes_from_dependent_job(dep_job)
+
+        artifacts_specifications = generate_specifications_of_artifacts_to_sign(
+            config,
+            job,
+            keep_locale_template=False,
+            kind=config.kind,
+            dep_kind=upstream_artifact_task.kind,
+        )
+
+        task_ref = f"<{upstream_artifact_task.kind}>"
+        task_type = "build"
+        if "notarization" in upstream_artifact_task.kind:
+            task_type = "scriptworker"
+
+        job["upstream-artifacts"] = [
+            {
+                "taskId": {"task-reference": task_ref},
+                "taskType": task_type,
+                "paths": spec["artifacts"],
+                "formats": spec["formats"],
+            }
+            for spec in artifacts_specifications
+        ]
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/cached_tasks.py b/taskcluster/gecko_taskgraph/transforms/cached_tasks.py
new file mode 100644
index 0000000000..bb7e6e6778
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/cached_tasks.py
@@ -0,0 +1,101 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from collections import deque
+
+import taskgraph
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.cached_tasks import add_optimization
+
+transforms = TransformSequence()
+
+
+def order_tasks(config, tasks):
+    """Iterate image tasks in an order where parent tasks come first."""
+    kind_prefix = config.kind + "-"
+
+    pending = deque(tasks)
+    task_labels = {task["label"] for task in pending}
+    emitted = set()
+    while True:
+        try:
+            task = pending.popleft()
+        except IndexError:
+            break
+        parents = {
+            task
+            for task in task.get("dependencies", {}).values()
+            if task.startswith(kind_prefix)
+        }
+        if parents and not emitted.issuperset(parents & task_labels):
+            pending.append(task)
+            continue
+        emitted.add(task["label"])
+        yield task
+
+
+def format_task_digest(cached_task):
+    return "/".join(
+        [
+            cached_task["type"],
+            cached_task["name"],
+            cached_task["digest"],
+        ]
+    )
+
+
+@transforms.add
+def cache_task(config, tasks):
+    if taskgraph.fast:
+        for task in tasks:
+            yield task
+        return
+
+    digests = {}
+    for task in config.kind_dependencies_tasks.values():
+        if (
+            "cached_task" in task.attributes
+            and task.attributes["cached_task"] is not False
+        ):
+            digests[task.label] = format_task_digest(task.attributes["cached_task"])
+
+    for task in order_tasks(config, tasks):
+        cache = task.pop("cache", None)
+        if cache is None:
+            yield task
+            continue
+
+        dependency_digests = []
+        for p in task.get("dependencies", {}).values():
+            if p in digests:
+                dependency_digests.append(digests[p])
+            elif config.params["project"] == "toolchains":
+                # The toolchains repository uses non-cached toolchain artifacts. Allow
+                # tasks to use them.
+                cache = None
+                break
+            else:
+                raise Exception(
+                    "Cached task {} has uncached parent task: {}".format(
+                        task["label"], p
+                    )
+                )
+
+        if cache is None:
+            yield task
+            continue
+
+        digest_data = cache["digest-data"] + sorted(dependency_digests)
+        add_optimization(
+            config,
+            task,
+            cache_type=cache["type"],
+            cache_name=cache["name"],
+            digest_data=digest_data,
+        )
+        digests[task["label"]] = format_task_digest(task["attributes"]["cached_task"])
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/chunk_partners.py b/taskcluster/gecko_taskgraph/transforms/chunk_partners.py
new file mode 100644
index 0000000000..ed74cc6232
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/chunk_partners.py
@@ -0,0 +1,75 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Chunk the partner repack tasks by subpartner and locale
+"""
+
+
+import copy
+
+from mozbuild.chunkify import chunkify
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.partners import (
+    apply_partner_priority,
+    get_repack_ids_by_platform,
+)
+
+transforms = TransformSequence()
+transforms.add(apply_partner_priority)
+
+
+@transforms.add
+def chunk_partners(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        build_platform = dep_job.attributes["build_platform"]
+        repack_id = dep_job.task.get("extra", {}).get("repack_id")
+        repack_ids = dep_job.task.get("extra", {}).get("repack_ids")
+        copy_repack_ids = job.pop("copy-repack-ids", False)
+
+        if copy_repack_ids:
+            assert repack_ids, "dep_job {} doesn't have repack_ids!".format(
+                dep_job.label
+            )
+            job.setdefault("extra", {})["repack_ids"] = repack_ids
+            yield job
+        # first downstream of the repack task, no chunking or fanout has been done yet
+        elif not any([repack_id, repack_ids]):
+            platform_repack_ids = get_repack_ids_by_platform(config, build_platform)
+            # we chunk mac signing
+            if config.kind in (
+                "release-partner-repack-signing",
+                "release-eme-free-repack-signing",
+                "release-eme-free-repack-mac-signing",
+                "release-partner-repack-mac-signing",
+            ):
+                repacks_per_chunk = job.get("repacks-per-chunk")
+                chunks, remainder = divmod(len(platform_repack_ids), repacks_per_chunk)
+                if remainder:
+                    chunks = int(chunks + 1)
+                for this_chunk in range(1, chunks + 1):
+                    chunk = chunkify(platform_repack_ids, this_chunk, chunks)
+                    partner_job = copy.deepcopy(job)
+                    partner_job.setdefault("extra", {}).setdefault("repack_ids", chunk)
+                    partner_job["extra"]["repack_suffix"] = str(this_chunk)
+                    yield partner_job
+            # linux and windows we fan out immediately to one task per partner-sub_partner-locale
+            else:
+                for repack_id in platform_repack_ids:
+                    partner_job = copy.deepcopy(job)  # don't overwrite dict values here
+                    partner_job.setdefault("extra", {})
+                    partner_job["extra"]["repack_id"] = repack_id
+                    yield partner_job
+        # fan out chunked mac signing for repackage
+        elif repack_ids:
+            for repack_id in repack_ids:
+                partner_job = copy.deepcopy(job)
+                partner_job.setdefault("extra", {}).setdefault("repack_id", repack_id)
+                yield partner_job
+        # otherwise we've fully fanned out already, continue by passing repack_id on
+        else:
+            partner_job = copy.deepcopy(job)
+            partner_job.setdefault("extra", {}).setdefault("repack_id", repack_id)
+            yield partner_job
diff --git a/taskcluster/gecko_taskgraph/transforms/code_review.py b/taskcluster/gecko_taskgraph/transforms/code_review.py
new file mode 100644
index 0000000000..d644e17d0e
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/code_review.py
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add soft dependencies and configuration to code-review tasks.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_dependencies(config, jobs):
+    for job in jobs:
+        job.setdefault("soft-dependencies", [])
+        job["soft-dependencies"] += [
+            dep_task.label
+            for dep_task in config.kind_dependencies_tasks.values()
+            if dep_task.attributes.get("code-review") is True
+        ]
+        yield job
+
+
+@transforms.add
+def add_phabricator_config(config, jobs):
+    for job in jobs:
+        diff = config.params.get("phabricator_diff")
+        if diff is not None:
+            code_review = job.setdefault("extra", {}).setdefault("code-review", {})
+            code_review["phabricator-diff"] = diff
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/condprof.py b/taskcluster/gecko_taskgraph/transforms/condprof.py
new file mode 100644
index 0000000000..34cf7e7dd3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/condprof.py
@@ -0,0 +1,85 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+This transform constructs tasks generate conditioned profiles from
+the condprof/kind.yml file
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema
+from voluptuous import Optional
+
+from gecko_taskgraph.transforms.job import job_description_schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.copy_task import copy_task
+
+diff_description_schema = Schema(
+    {
+        # default is settled, but add 'full' to get both
+        Optional("scenarios"): [str],
+        Optional("description"): task_description_schema["description"],
+        Optional("dependencies"): task_description_schema["dependencies"],
+        Optional("fetches"): job_description_schema["fetches"],
+        Optional("index"): task_description_schema["index"],
+        Optional("job-from"): str,
+        Optional("name"): str,
+        Optional("run"): job_description_schema["run"],
+        Optional("run-on-projects"): task_description_schema["run-on-projects"],
+        Optional("scopes"): task_description_schema["scopes"],
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("worker"): job_description_schema["worker"],
+        Optional("worker-type"): task_description_schema["worker-type"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(diff_description_schema)
+
+
+@transforms.add
+def generate_scenarios(config, tasks):
+    for task in tasks:
+        cmds = task["run"]["command"]
+        symbol = task["treeherder"]["symbol"].split(")")[0]
+        index = task["index"]
+        jobname = index["job-name"]
+        label = task["name"]
+        run_as_root = task["run"].get("run-as-root", False)
+
+        for scenario in set(task["scenarios"]):
+            extra_args = ""
+            if scenario == "settled":
+                extra_args = " --force-new "
+
+            tcmd = cmds.replace("${EXTRA_ARGS}", extra_args)
+            tcmd = tcmd.replace("${SCENARIO}", scenario)
+
+            index["job-name"] = "%s-%s" % (jobname, scenario)
+
+            taskdesc = {
+                "name": "%s-%s" % (label, scenario),
+                "description": task["description"],
+                "treeherder": {
+                    "symbol": "%s-%s)" % (symbol, scenario),
+                    "platform": task["treeherder"]["platform"],
+                    "kind": task["treeherder"]["kind"],
+                    "tier": task["treeherder"]["tier"],
+                },
+                "worker-type": copy_task(task["worker-type"]),
+                "worker": copy_task(task["worker"]),
+                "index": copy_task(index),
+                "run": {
+                    "using": "run-task",
+                    "cwd": task["run"]["cwd"],
+                    "checkout": task["run"]["checkout"],
+                    "tooltool-downloads": copy_task(task["run"]["tooltool-downloads"]),
+                    "command": tcmd,
+                    "run-as-root": run_as_root,
+                },
+                "run-on-projects": copy_task(task["run-on-projects"]),
+                "scopes": copy_task(task["scopes"]),
+                "dependencies": copy_task(task["dependencies"]),
+                "fetches": copy_task(task["fetches"]),
+            }
+            yield taskdesc
diff --git a/taskcluster/gecko_taskgraph/transforms/copy_attributes_from_dependent_task.py b/taskcluster/gecko_taskgraph/transforms/copy_attributes_from_dependent_task.py
new file mode 100644
index 0000000000..281dd5938f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/copy_attributes_from_dependent_task.py
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def copy_attributes(config, jobs):
+    for job in jobs:
+        job.setdefault("attributes", {})
+        job["attributes"].update(
+            copy_attributes_from_dependent_job(job["primary-dependency"])
+        )
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/cross_channel.py b/taskcluster/gecko_taskgraph/transforms/cross_channel.py
new file mode 100644
index 0000000000..bf6d3a3a4f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/cross_channel.py
@@ -0,0 +1,44 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Build a command to run `mach l10n-cross-channel`.
+"""
+
+
+from pipes import quote as shell_quote
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        for item in ["ssh-key-secret", "run.actions"]:
+            resolve_keyed_by(job, item, item, **{"level": str(config.params["level"])})
+        yield job
+
+
+@transforms.add
+def build_command(config, jobs):
+    for job in jobs:
+        command = [
+            "l10n-cross-channel",
+            "-o",
+            "/builds/worker/artifacts/outgoing.diff",
+            "--attempts",
+            "5",
+        ]
+        ssh_key_secret = job.pop("ssh-key-secret")
+        if ssh_key_secret:
+            command.extend(["--ssh-secret", ssh_key_secret])
+            job.setdefault("scopes", []).append(f"secrets:get:{ssh_key_secret}")
+
+        command.extend(job["run"].pop("actions", []))
+        job.setdefault("run", {}).update(
+            {"using": "mach", "mach": " ".join(map(shell_quote, command))}
+        )
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/diffoscope.py b/taskcluster/gecko_taskgraph/transforms/diffoscope.py
new file mode 100644
index 0000000000..b74dc5bb8f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/diffoscope.py
@@ -0,0 +1,172 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+This transform construct tasks to perform diffs between builds, as
+defined in kind.yml
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema
+from taskgraph.util.taskcluster import get_artifact_path
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.transforms.task import task_description_schema
+
+index_or_string = Any(
+    str,
+    {Required("index-search"): str},
+)
+
+diff_description_schema = Schema(
+    {
+        # Name of the diff task.
+        Required("name"): str,
+        # Treeherder tier.
+        Required("tier"): int,
+        # Treeherder symbol.
+        Required("symbol"): str,
+        # relative path (from config.path) to the file the task was defined in.
+        Optional("job-from"): str,
+        # Original and new builds to compare.
+        Required("original"): index_or_string,
+        Required("new"): index_or_string,
+        # Arguments to pass to diffoscope, used for job-defaults in
+        # taskcluster/ci/diffoscope/kind.yml
+        Optional("args"): str,
+        # Extra arguments to pass to diffoscope, that can be set per job.
+        Optional("extra-args"): str,
+        # Fail the task when differences are detected.
+        Optional("fail-on-diff"): bool,
+        # What artifact to check the differences of. Defaults to target.tar.bz2
+        # for Linux, target.dmg for Mac, target.zip for Windows, target.apk for
+        # Android.
+        Optional("artifact"): str,
+        # Whether to unpack first. Diffoscope can normally work without unpacking,
+        # but when one needs to --exclude some contents, that doesn't work out well
+        # if said content is packed (e.g. in omni.ja).
+        Optional("unpack"): bool,
+        # Commands to run before performing the diff.
+        Optional("pre-diff-commands"): [str],
+        # Only run the task on a set of projects/branches.
+        Optional("run-on-projects"): task_description_schema["run-on-projects"],
+        Optional("optimization"): task_description_schema["optimization"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(diff_description_schema)
+
+
+@transforms.add
+def fill_template(config, tasks):
+    dummy_tasks = {}
+
+    for task in tasks:
+        name = task["name"]
+
+        deps = {}
+        urls = {}
+        previous_artifact = None
+        artifact = task.get("artifact")
+        for k in ("original", "new"):
+            value = task[k]
+            if isinstance(value, str):
+                deps[k] = value
+                dep_name = k
+                os_hint = value
+            else:
+                index = value["index-search"]
+                if index not in dummy_tasks:
+                    dummy_tasks[index] = {
+                        "label": "index-search-" + index,
+                        "description": index,
+                        "worker-type": "invalid/always-optimized",
+                        "run": {
+                            "using": "always-optimized",
+                        },
+                        "optimization": {
+                            "index-search": [index],
+                        },
+                    }
+                    yield dummy_tasks[index]
+                deps[index] = "index-search-" + index
+                dep_name = index
+                os_hint = index.split(".")[-1]
+            if artifact:
+                pass
+            elif "linux" in os_hint:
+                artifact = "target.tar.bz2"
+            elif "macosx" in os_hint:
+                artifact = "target.dmg"
+            elif "android" in os_hint:
+                artifact = "target.apk"
+            elif "win" in os_hint:
+                artifact = "target.zip"
+            else:
+                raise Exception(f"Cannot figure out the OS for {value!r}")
+            if previous_artifact is not None and previous_artifact != artifact:
+                raise Exception("Cannot compare builds from different OSes")
+            urls[k] = {
+                "artifact-reference": "<{}/{}>".format(
+                    dep_name, get_artifact_path(task, artifact)
+                ),
+            }
+            previous_artifact = artifact
+
+        taskdesc = {
+            "label": "diff-" + name,
+            "description": name,
+            "treeherder": {
+                "symbol": task["symbol"],
+                "platform": "diff/opt",
+                "kind": "other",
+                "tier": task["tier"],
+            },
+            "worker-type": "b-linux-gcp",
+            "worker": {
+                "docker-image": {"in-tree": "diffoscope"},
+                "artifacts": [
+                    {
+                        "type": "file",
+                        "path": f"/builds/worker/{f}",
+                        "name": f"public/{f}",
+                    }
+                    for f in (
+                        "diff.html",
+                        "diff.txt",
+                    )
+                ],
+                "env": {
+                    "ORIG_URL": urls["original"],
+                    "NEW_URL": urls["new"],
+                    "DIFFOSCOPE_ARGS": " ".join(
+                        task[k] for k in ("args", "extra-args") if k in task
+                    ),
+                    "PRE_DIFF": "; ".join(task.get("pre-diff-commands", [])),
+                },
+                "max-run-time": 1800,
+            },
+            "run": {
+                "using": "run-task",
+                "checkout": task.get("unpack", False),
+                "command": "/builds/worker/bin/get_and_diffoscope{}{}".format(
+                    " --unpack" if task.get("unpack") else "",
+                    " --fail" if task.get("fail-on-diff") else "",
+                ),
+            },
+            "dependencies": deps,
+            "optimization": task.get("optimization"),
+        }
+        if "run-on-projects" in task:
+            taskdesc["run-on-projects"] = task["run-on-projects"]
+
+        if artifact.endswith(".dmg"):
+            taskdesc.setdefault("fetches", {}).setdefault("toolchain", []).extend(
+                [
+                    "linux64-cctools-port",
+                    "linux64-libdmg",
+                ]
+            )
+
+        yield taskdesc
diff --git a/taskcluster/gecko_taskgraph/transforms/docker_image.py b/taskcluster/gecko_taskgraph/transforms/docker_image.py
new file mode 100644
index 0000000000..0ccf83bf38
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/docker_image.py
@@ -0,0 +1,209 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+import os
+import re
+
+import mozpack.path as mozpath
+import taskgraph
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.util.docker import (
+    create_context_tar,
+    generate_context_hash,
+    image_path,
+)
+
+from .. import GECKO
+from .task import task_description_schema
+
+logger = logging.getLogger(__name__)
+
+CONTEXTS_DIR = "docker-contexts"
+
+DIGEST_RE = re.compile("^[0-9a-f]{64}$")
+
+IMAGE_BUILDER_IMAGE = (
+    "mozillareleases/image_builder:5.0.0"
+    "@sha256:"
+    "e510a9a9b80385f71c112d61b2f2053da625aff2b6d430411ac42e424c58953f"
+)
+
+transforms = TransformSequence()
+
+docker_image_schema = Schema(
+    {
+        # Name of the docker image.
+        Required("name"): str,
+        # Name of the parent docker image.
+        Optional("parent"): str,
+        # Treeherder symbol.
+        Required("symbol"): str,
+        # relative path (from config.path) to the file the docker image was defined
+        # in.
+        Optional("job-from"): str,
+        # Arguments to use for the Dockerfile.
+        Optional("args"): {str: str},
+        # Name of the docker image definition under taskcluster/docker, when
+        # different from the docker image name.
+        Optional("definition"): str,
+        # List of package tasks this docker image depends on.
+        Optional("packages"): [str],
+        Optional(
+            "index",
+            description="information for indexing this build so its artifacts can be discovered",
+        ): task_description_schema["index"],
+        Optional(
+            "cache",
+            description="Whether this image should be cached based on inputs.",
+        ): bool,
+    }
+)
+
+
+transforms.add_validate(docker_image_schema)
+
+
+@transforms.add
+def fill_template(config, tasks):
+    if not taskgraph.fast and config.write_artifacts:
+        if not os.path.isdir(CONTEXTS_DIR):
+            os.makedirs(CONTEXTS_DIR)
+
+    for task in tasks:
+        image_name = task.pop("name")
+        job_symbol = task.pop("symbol")
+        args = task.pop("args", {})
+        packages = task.pop("packages", [])
+        parent = task.pop("parent", None)
+
+        for p in packages:
+            if f"packages-{p}" not in config.kind_dependencies_tasks:
+                raise Exception(
+                    "Missing package job for {}-{}: {}".format(
+                        config.kind, image_name, p
+                    )
+                )
+
+        if not taskgraph.fast:
+            context_path = mozpath.relpath(image_path(image_name), GECKO)
+            if config.write_artifacts:
+                context_file = os.path.join(CONTEXTS_DIR, f"{image_name}.tar.gz")
+                logger.info(f"Writing {context_file} for docker image {image_name}")
+                context_hash = create_context_tar(
+                    GECKO, context_path, context_file, image_name, args
+                )
+            else:
+                context_hash = generate_context_hash(
+                    GECKO, context_path, image_name, args
+                )
+        else:
+            if config.write_artifacts:
+                raise Exception("Can't write artifacts if `taskgraph.fast` is set.")
+            context_hash = "0" * 40
+        digest_data = [context_hash]
+        digest_data += [json.dumps(args, sort_keys=True)]
+
+        description = "Build the docker image {} for use by dependent tasks".format(
+            image_name
+        )
+
+        args["DOCKER_IMAGE_PACKAGES"] = " ".join(f"<{p}>" for p in packages)
+
+        # Adjust the zstandard compression level based on the execution level.
+        # We use faster compression for level 1 because we care more about
+        # end-to-end times. We use slower/better compression for other levels
+        # because images are read more often and it is worth the trade-off to
+        # burn more CPU once to reduce image size.
+        zstd_level = "3" if int(config.params["level"]) == 1 else "10"
+
+        # include some information that is useful in reconstructing this task
+        # from JSON
+        taskdesc = {
+            "label": f"{config.kind}-{image_name}",
+            "description": description,
+            "attributes": {
+                "image_name": image_name,
+                "artifact_prefix": "public",
+            },
+            "expiration-policy": "long",
+            "scopes": [],
+            "treeherder": {
+                "symbol": job_symbol,
+                "platform": "taskcluster-images/opt",
+                "kind": "other",
+                "tier": 1,
+            },
+            "run-on-projects": [],
+            "worker-type": "images-gcp",
+            "worker": {
+                "implementation": "docker-worker",
+                "os": "linux",
+                "artifacts": [
+                    {
+                        "type": "file",
+                        "path": "/workspace/image.tar.zst",
+                        "name": "public/image.tar.zst",
+                    }
+                ],
+                "env": {
+                    "CONTEXT_TASK_ID": {"task-reference": "<decision>"},
+                    "CONTEXT_PATH": "public/docker-contexts/{}.tar.gz".format(
+                        image_name
+                    ),
+                    "HASH": context_hash,
+                    "PROJECT": config.params["project"],
+                    "IMAGE_NAME": image_name,
+                    "DOCKER_IMAGE_ZSTD_LEVEL": zstd_level,
+                    "DOCKER_BUILD_ARGS": {"task-reference": json.dumps(args)},
+                    "GECKO_BASE_REPOSITORY": config.params["base_repository"],
+                    "GECKO_HEAD_REPOSITORY": config.params["head_repository"],
+                    "GECKO_HEAD_REV": config.params["head_rev"],
+                },
+                "chain-of-trust": True,
+                "max-run-time": 7200,
+                # FIXME: We aren't currently propagating the exit code
+            },
+        }
+        # Retry for 'funsize-update-generator' if exit status code is -1
+        if image_name in ["funsize-update-generator"]:
+            taskdesc["worker"]["retry-exit-status"] = [-1]
+
+        worker = taskdesc["worker"]
+
+        if image_name == "image_builder":
+            worker["docker-image"] = IMAGE_BUILDER_IMAGE
+            digest_data.append(f"image-builder-image:{IMAGE_BUILDER_IMAGE}")
+        else:
+            worker["docker-image"] = {"in-tree": "image_builder"}
+            deps = taskdesc.setdefault("dependencies", {})
+            deps["docker-image"] = f"{config.kind}-image_builder"
+
+        if packages:
+            deps = taskdesc.setdefault("dependencies", {})
+            for p in sorted(packages):
+                deps[p] = f"packages-{p}"
+
+        if parent:
+            deps = taskdesc.setdefault("dependencies", {})
+            deps["parent"] = f"{config.kind}-{parent}"
+            worker["env"]["PARENT_TASK_ID"] = {
+                "task-reference": "<parent>",
+            }
+        if "index" in task:
+            taskdesc["index"] = task["index"]
+
+        if task.get("cache", True) and not taskgraph.fast:
+            taskdesc["cache"] = {
+                "type": "docker-images.v2",
+                "name": image_name,
+                "digest-data": digest_data,
+            }
+
+        yield taskdesc
diff --git a/taskcluster/gecko_taskgraph/transforms/fetch.py b/taskcluster/gecko_taskgraph/transforms/fetch.py
new file mode 100644
index 0000000000..b51362a905
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/fetch.py
@@ -0,0 +1,387 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Support for running tasks that download remote content and re-export
+# it as task artifacts.
+
+
+import os
+import re
+
+import attr
+import taskgraph
+from mozbuild.shellutil import quote as shell_quote
+from mozpack import path as mozpath
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, validate_schema
+from taskgraph.util.treeherder import join_symbol
+from voluptuous import Any, Extra, Optional, Required
+
+import gecko_taskgraph
+
+from ..util.cached_tasks import add_optimization
+
+CACHE_TYPE = "content.v1"
+
+FETCH_SCHEMA = Schema(
+    {
+        # Name of the task.
+        Required("name"): str,
+        # Relative path (from config.path) to the file the task was defined
+        # in.
+        Optional("job-from"): str,
+        # Description of the task.
+        Required("description"): str,
+        Optional(
+            "fetch-alias",
+            description="An alias that can be used instead of the real fetch job name in "
+            "fetch stanzas for jobs.",
+        ): str,
+        Optional(
+            "artifact-prefix",
+            description="The prefix of the taskcluster artifact being uploaded. "
+            "Defaults to `public/`; if it starts with something other than "
+            "`public/` the artifact will require scopes to access.",
+        ): str,
+        Optional("attributes"): {str: object},
+        Required("fetch"): {
+            Required("type"): str,
+            Extra: object,
+        },
+    }
+)
+
+
+# define a collection of payload builders, depending on the worker implementation
+fetch_builders = {}
+
+
+@attr.s(frozen=True)
+class FetchBuilder:
+    schema = attr.ib(type=Schema)
+    builder = attr.ib()
+
+
+def fetch_builder(name, schema):
+    schema = Schema({Required("type"): name}).extend(schema)
+
+    def wrap(func):
+        fetch_builders[name] = FetchBuilder(schema, func)
+        return func
+
+    return wrap
+
+
+transforms = TransformSequence()
+transforms.add_validate(FETCH_SCHEMA)
+
+
+@transforms.add
+def process_fetch_job(config, jobs):
+    # Converts fetch-url entries to the job schema.
+    for job in jobs:
+        typ = job["fetch"]["type"]
+        name = job["name"]
+        fetch = job.pop("fetch")
+
+        if typ not in fetch_builders:
+            raise Exception(f"Unknown fetch type {typ} in fetch {name}")
+        validate_schema(fetch_builders[typ].schema, fetch, f"In task.fetch {name!r}:")
+
+        job.update(configure_fetch(config, typ, name, fetch))
+
+        yield job
+
+
+def configure_fetch(config, typ, name, fetch):
+    if typ not in fetch_builders:
+        raise Exception(f"No fetch type {typ} in fetch {name}")
+    validate_schema(fetch_builders[typ].schema, fetch, f"In task.fetch {name!r}:")
+
+    return fetch_builders[typ].builder(config, name, fetch)
+
+
+@transforms.add
+def make_task(config, jobs):
+    # Fetch tasks are idempotent and immutable. Have them live for
+    # essentially forever.
+    if config.params["level"] == "3":
+        expires = "1000 years"
+    else:
+        expires = "28 days"
+
+    for job in jobs:
+        name = job["name"]
+        artifact_prefix = job.get("artifact-prefix", "public")
+        env = job.get("env", {})
+        env.update({"UPLOAD_DIR": "/builds/worker/artifacts"})
+        attributes = job.get("attributes", {})
+        attributes["fetch-artifact"] = mozpath.join(
+            artifact_prefix, job["artifact_name"]
+        )
+        alias = job.get("fetch-alias")
+        if alias:
+            attributes["fetch-alias"] = alias
+
+        task_expires = "28 days" if attributes.get("cached_task") is False else expires
+        artifact_expires = (
+            "2 days" if attributes.get("cached_task") is False else expires
+        )
+
+        task = {
+            "attributes": attributes,
+            "name": name,
+            "description": job["description"],
+            "expires-after": task_expires,
+            "label": "fetch-%s" % name,
+            "run-on-projects": [],
+            "treeherder": {
+                "symbol": join_symbol("Fetch", name),
+                "kind": "build",
+                "platform": "fetch/opt",
+                "tier": 1,
+            },
+            "run": {
+                "using": "run-task",
+                "checkout": False,
+                "command": job["command"],
+            },
+            "worker-type": "b-linux-gcp",
+            "worker": {
+                "chain-of-trust": True,
+                "docker-image": {"in-tree": "fetch"},
+                "env": env,
+                "max-run-time": 900,
+                "artifacts": [
+                    {
+                        "type": "directory",
+                        "name": artifact_prefix,
+                        "path": "/builds/worker/artifacts",
+                        "expires-after": artifact_expires,
+                    }
+                ],
+            },
+        }
+
+        if job.get("secret", None):
+            task["scopes"] = ["secrets:get:" + job.get("secret")]
+            task["worker"]["taskcluster-proxy"] = True
+
+        if not taskgraph.fast:
+            cache_name = task["label"].replace(f"{config.kind}-", "", 1)
+
+            # This adds the level to the index path automatically.
+            add_optimization(
+                config,
+                task,
+                cache_type=CACHE_TYPE,
+                cache_name=cache_name,
+                digest_data=job["digest_data"],
+            )
+        yield task
+
+
+@fetch_builder(
+    "static-url",
+    schema={
+        # The URL to download.
+        Required("url"): str,
+        # The SHA-256 of the downloaded content.
+        Required("sha256"): str,
+        # Size of the downloaded entity, in bytes.
+        Required("size"): int,
+        # GPG signature verification.
+        Optional("gpg-signature"): {
+            # URL where GPG signature document can be obtained. Can contain the
+            # value ``{url}``, which will be substituted with the value from
+            # ``url``.
+            Required("sig-url"): str,
+            # Path to file containing GPG public key(s) used to validate
+            # download.
+            Required("key-path"): str,
+        },
+        # The name to give to the generated artifact. Defaults to the file
+        # portion of the URL. Using a different extension converts the
+        # archive to the given type. Only conversion to .tar.zst is
+        # supported.
+        Optional("artifact-name"): str,
+        # Strip the given number of path components at the beginning of
+        # each file entry in the archive.
+        # Requires an artifact-name ending with .tar.zst.
+        Optional("strip-components"): int,
+        # Add the given prefix to each file entry in the archive.
+        # Requires an artifact-name ending with .tar.zst.
+        Optional("add-prefix"): str,
+        # IMPORTANT: when adding anything that changes the behavior of the task,
+        # it is important to update the digest data used to compute cache hits.
+    },
+)
+def create_fetch_url_task(config, name, fetch):
+    artifact_name = fetch.get("artifact-name")
+    if not artifact_name:
+        artifact_name = fetch["url"].split("/")[-1]
+
+    command = [
+        "/builds/worker/bin/fetch-content",
+        "static-url",
+    ]
+
+    # Arguments that matter to the cache digest
+    args = [
+        "--sha256",
+        fetch["sha256"],
+        "--size",
+        "%d" % fetch["size"],
+    ]
+
+    if fetch.get("strip-components"):
+        args.extend(["--strip-components", "%d" % fetch["strip-components"]])
+
+    if fetch.get("add-prefix"):
+        args.extend(["--add-prefix", fetch["add-prefix"]])
+
+    command.extend(args)
+
+    env = {}
+
+    if "gpg-signature" in fetch:
+        sig_url = fetch["gpg-signature"]["sig-url"].format(url=fetch["url"])
+        key_path = os.path.join(
+            gecko_taskgraph.GECKO, fetch["gpg-signature"]["key-path"]
+        )
+
+        with open(key_path, "r") as fh:
+            gpg_key = fh.read()
+
+        env["FETCH_GPG_KEY"] = gpg_key
+        command.extend(
+            [
+                "--gpg-sig-url",
+                sig_url,
+                "--gpg-key-env",
+                "FETCH_GPG_KEY",
+            ]
+        )
+
+    command.extend(
+        [
+            fetch["url"],
+            "/builds/worker/artifacts/%s" % artifact_name,
+        ]
+    )
+
+    return {
+        "command": command,
+        "artifact_name": artifact_name,
+        "env": env,
+        # We don't include the GPG signature in the digest because it isn't
+        # materially important for caching: GPG signatures are supplemental
+        # trust checking beyond what the shasum already provides.
+        "digest_data": args + [artifact_name],
+    }
+
+
+@fetch_builder(
+    "git",
+    schema={
+        Required("repo"): str,
+        Required(Any("revision", "branch")): str,
+        Optional("include-dot-git"): bool,
+        Optional("artifact-name"): str,
+        Optional("path-prefix"): str,
+        # ssh-key is a taskcluster secret path (e.g. project/civet/github-deploy-key)
+        # In the secret dictionary, the key should be specified as
+        #  "ssh_privkey": "-----BEGIN OPENSSH PRIVATE KEY-----\nkfksnb3jc..."
+        # n.b. The OpenSSH private key file format requires a newline at the end of the file.
+        Optional("ssh-key"): str,
+    },
+)
+def create_git_fetch_task(config, name, fetch):
+    path_prefix = fetch.get("path-prefix")
+    if not path_prefix:
+        path_prefix = fetch["repo"].rstrip("/").rsplit("/", 1)[-1]
+    artifact_name = fetch.get("artifact-name")
+    if not artifact_name:
+        artifact_name = f"{path_prefix}.tar.zst"
+
+    if "revision" in fetch and "branch" in fetch:
+        raise Exception("revision and branch cannot be used in the same context")
+
+    revision_or_branch = None
+
+    if "revision" in fetch:
+        revision_or_branch = fetch["revision"]
+        if not re.match(r"[0-9a-fA-F]{40}", fetch["revision"]):
+            raise Exception(f'Revision is not a sha1 in fetch task "{name}"')
+    else:
+        # we are sure we are dealing with a branch
+        revision_or_branch = fetch["branch"]
+
+    args = [
+        "/builds/worker/bin/fetch-content",
+        "git-checkout-archive",
+        "--path-prefix",
+        path_prefix,
+        fetch["repo"],
+        revision_or_branch,
+        "/builds/worker/artifacts/%s" % artifact_name,
+    ]
+
+    ssh_key = fetch.get("ssh-key")
+    if ssh_key:
+        args.append("--ssh-key-secret")
+        args.append(ssh_key)
+
+    digest_data = [revision_or_branch, path_prefix, artifact_name]
+    if fetch.get("include-dot-git", False):
+        args.append("--include-dot-git")
+        digest_data.append(".git")
+
+    return {
+        "command": args,
+        "artifact_name": artifact_name,
+        "digest_data": digest_data,
+        "secret": ssh_key,
+    }
+
+
+@fetch_builder(
+    "chromium-fetch",
+    schema={
+        Required("script"): str,
+        # Platform type for chromium build
+        Required("platform"): str,
+        # Chromium revision to obtain
+        Optional("revision"): str,
+        # The name to give to the generated artifact.
+        Required("artifact-name"): str,
+    },
+)
+def create_chromium_fetch_task(config, name, fetch):
+    artifact_name = fetch.get("artifact-name")
+
+    workdir = "/builds/worker"
+
+    platform = fetch.get("platform")
+    revision = fetch.get("revision")
+
+    args = "--platform " + shell_quote(platform)
+    if revision:
+        args += " --revision " + shell_quote(revision)
+
+    cmd = [
+        "bash",
+        "-c",
+        "cd {} && " "/usr/bin/python3 {} {}".format(workdir, fetch["script"], args),
+    ]
+
+    return {
+        "command": cmd,
+        "artifact_name": artifact_name,
+        "digest_data": [
+            f"revision={revision}",
+            f"platform={platform}",
+            f"artifact_name={artifact_name}",
+        ],
+    }
diff --git a/taskcluster/gecko_taskgraph/transforms/final_verify.py b/taskcluster/gecko_taskgraph/transforms/final_verify.py
new file mode 100644
index 0000000000..aa8be35a0d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/final_verify.py
@@ -0,0 +1,35 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_command(config, tasks):
+    for task in tasks:
+        if not task["worker"].get("env"):
+            task["worker"]["env"] = {}
+
+        final_verify_configs = []
+        for upstream in sorted(task.get("dependencies", {}).keys()):
+            if "update-verify-config" in upstream:
+                final_verify_configs.append(
+                    f"<{upstream}/public/build/update-verify.cfg>",
+                )
+        task["run"] = {
+            "using": "run-task",
+            "cwd": "{checkout}",
+            "command": {
+                "artifact-reference": "tools/update-verify/release/final-verification.sh "
+                + " ".join(final_verify_configs),
+            },
+            "sparse-profile": "update-verify",
+        }
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/fxrecord.py b/taskcluster/gecko_taskgraph/transforms/fxrecord.py
new file mode 100644
index 0000000000..0d8a23bfb4
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/fxrecord.py
@@ -0,0 +1,22 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def fxrecord(config, jobs):
+    for job in jobs:
+        dep_job = job.pop("primary-dependency", None)
+
+        if dep_job is not None:
+            job["dependencies"] = {dep_job.label: dep_job.label}
+            job["treeherder"]["platform"] = dep_job.task["extra"]["treeherder-platform"]
+            job["worker"].setdefault("env", {})["FXRECORD_TASK_ID"] = {
+                "task-reference": f"<{dep_job.label}>"
+            }
+
+            yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/geckodriver_mac_notarization.py b/taskcluster/gecko_taskgraph/transforms/geckodriver_mac_notarization.py
new file mode 100644
index 0000000000..1a996c1fc4
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/geckodriver_mac_notarization.py
@@ -0,0 +1,68 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import add_scope_prefix
+
+repackage_signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("worker"): task_description_schema["worker"],
+        Optional("worker-type"): task_description_schema["worker-type"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(repackage_signing_description_schema)
+
+
+@transforms.add
+def geckodriver_mac_notarization(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        treeherder = job.get("treeherder", {})
+        dep_treeherder = dep_job.task.get("extra", {}).get("treeherder", {})
+        treeherder.setdefault(
+            "platform", dep_job.task.get("extra", {}).get("treeherder-platform")
+        )
+        treeherder.setdefault("tier", dep_treeherder.get("tier", 1))
+        treeherder.setdefault("kind", "build")
+
+        dependencies = {dep_job.kind: dep_job.label}
+
+        description = "Mac notarization - Geckodriver for build '{}'".format(
+            attributes.get("build_platform"),
+        )
+
+        build_platform = dep_job.attributes.get("build_platform")
+
+        scopes = [add_scope_prefix(config, "signing:cert:release-apple-notarization")]
+
+        platform = build_platform.rsplit("-", 1)[0]
+
+        task = {
+            "label": job["label"],
+            "description": description,
+            "worker-type": job["worker-type"],
+            "worker": job["worker"],
+            "scopes": scopes,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "treeherder": treeherder,
+            "run-on-projects": ["mozilla-central"],
+            "index": {"product": "geckodriver", "job-name": f"{platform}-notarized"},
+        }
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/geckodriver_signing.py b/taskcluster/gecko_taskgraph/transforms/geckodriver_signing.py
new file mode 100644
index 0000000000..05bc1319de
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/geckodriver_signing.py
@@ -0,0 +1,124 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope_per_platform
+
+repackage_signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(repackage_signing_description_schema)
+
+
+@transforms.add
+def make_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes["repackage_type"] = "repackage-signing"
+
+        treeherder = job.get("treeherder", {})
+        dep_treeherder = dep_job.task.get("extra", {}).get("treeherder", {})
+        treeherder.setdefault(
+            "symbol", "{}(gd-s)".format(dep_treeherder["groupSymbol"])
+        )
+        treeherder.setdefault(
+            "platform", dep_job.task.get("extra", {}).get("treeherder-platform")
+        )
+        treeherder.setdefault("tier", dep_treeherder.get("tier", 1))
+        treeherder.setdefault("kind", "build")
+
+        dependencies = {dep_job.kind: dep_job.label}
+        signing_dependencies = dep_job.dependencies
+        dependencies.update(
+            {k: v for k, v in signing_dependencies.items() if k != "docker-image"}
+        )
+
+        description = "Signing Geckodriver for build '{}'".format(
+            attributes.get("build_platform"),
+        )
+
+        build_platform = dep_job.attributes.get("build_platform")
+        is_shippable = dep_job.attributes.get("shippable")
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_shippable, config
+        )
+
+        upstream_artifacts = _craft_upstream_artifacts(
+            dep_job, dep_job.kind, build_platform
+        )
+
+        scopes = [signing_cert_scope]
+
+        platform = build_platform.rsplit("-", 1)[0]
+
+        task = {
+            "label": job["label"],
+            "description": description,
+            "worker-type": "linux-signing",
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+            },
+            "scopes": scopes,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "treeherder": treeherder,
+            "run-on-projects": ["mozilla-central"],
+            "index": {"product": "geckodriver", "job-name": platform},
+        }
+
+        if build_platform.startswith("macosx"):
+            worker_type = task["worker-type"]
+            worker_type_alias_map = {
+                "linux-depsigning": "mac-depsigning",
+                "linux-signing": "mac-signing",
+            }
+
+            assert worker_type in worker_type_alias_map, (
+                "Make sure to adjust the below worker_type_alias logic for "
+                "mac if you change the signing workerType aliases!"
+                " ({} not found in mapping)".format(worker_type)
+            )
+            worker_type = worker_type_alias_map[worker_type]
+
+            task["worker-type"] = worker_type_alias_map[task["worker-type"]]
+            task["worker"]["mac-behavior"] = "mac_geckodriver"
+
+        yield task
+
+
+def _craft_upstream_artifacts(dep_job, dependency_kind, build_platform):
+    if build_platform.startswith("win"):
+        signing_format = "autograph_authenticode_sha2"
+    elif build_platform.startswith("linux"):
+        signing_format = "autograph_gpg"
+    elif build_platform.startswith("macosx"):
+        signing_format = "mac_geckodriver"
+    else:
+        raise ValueError(f'Unsupported build platform "{build_platform}"')
+
+    return [
+        {
+            "taskId": {"task-reference": f"<{dependency_kind}>"},
+            "taskType": "build",
+            "paths": [dep_job.attributes["toolchain-artifact"]],
+            "formats": [signing_format],
+        }
+    ]
diff --git a/taskcluster/gecko_taskgraph/transforms/github_sync.py b/taskcluster/gecko_taskgraph/transforms/github_sync.py
new file mode 100644
index 0000000000..6f48f794ce
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/github_sync.py
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def sync_github(config, tasks):
+    """Do transforms specific to github-sync tasks."""
+    for task in tasks:
+        # Add the secret to the scopes, only in m-c.
+        # Doing this on any other tree will result in decision task failure
+        # because m-c is the only one allowed to have that scope.
+        secret = task["secret"]
+        if config.params["project"] == "mozilla-central":
+            task.setdefault("scopes", [])
+            task["scopes"].append("secrets:get:" + secret)
+            task["worker"].setdefault("env", {})["GITHUB_SECRET"] = secret
+        del task["secret"]
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/job/__init__.py b/taskcluster/gecko_taskgraph/transforms/job/__init__.py
new file mode 100644
index 0000000000..9b6924b605
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/__init__.py
@@ -0,0 +1,504 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Convert a job description into a task description.
+
+Jobs descriptions are similar to task descriptions, but they specify how to run
+the job at a higher level, using a "run" field that can be interpreted by
+run-using handlers in `taskcluster/gecko_taskgraph/transforms/job`.
+"""
+
+
+import json
+import logging
+
+import mozpack.path as mozpath
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.python_path import import_sibling_modules
+from taskgraph.util.schema import Schema, validate_schema
+from taskgraph.util.taskcluster import get_artifact_prefix
+from voluptuous import Any, Exclusive, Extra, Optional, Required
+
+from gecko_taskgraph.transforms.cached_tasks import order_tasks
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.copy_task import copy_task
+from gecko_taskgraph.util.workertypes import worker_type_implementation
+
+logger = logging.getLogger(__name__)
+
+# Schema for a build description
+job_description_schema = Schema(
+    {
+        # The name of the job and the job's label.  At least one must be specified,
+        # and the label will be generated from the name if necessary, by prepending
+        # the kind.
+        Optional("name"): str,
+        Optional("label"): str,
+        # the following fields are passed directly through to the task description,
+        # possibly modified by the run implementation.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details.
+        Required("description"): task_description_schema["description"],
+        Optional("attributes"): task_description_schema["attributes"],
+        Optional("job-from"): task_description_schema["job-from"],
+        Optional("dependencies"): task_description_schema["dependencies"],
+        Optional("if-dependencies"): task_description_schema["if-dependencies"],
+        Optional("soft-dependencies"): task_description_schema["soft-dependencies"],
+        Optional("if-dependencies"): task_description_schema["if-dependencies"],
+        Optional("requires"): task_description_schema["requires"],
+        Optional("expires-after"): task_description_schema["expires-after"],
+        Optional("expiration-policy"): task_description_schema["expiration-policy"],
+        Optional("routes"): task_description_schema["routes"],
+        Optional("scopes"): task_description_schema["scopes"],
+        Optional("tags"): task_description_schema["tags"],
+        Optional("extra"): task_description_schema["extra"],
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("index"): task_description_schema["index"],
+        Optional("run-on-projects"): task_description_schema["run-on-projects"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("always-target"): task_description_schema["always-target"],
+        Exclusive("optimization", "optimization"): task_description_schema[
+            "optimization"
+        ],
+        Optional("use-sccache"): task_description_schema["use-sccache"],
+        Optional("use-system-python"): bool,
+        Optional("priority"): task_description_schema["priority"],
+        # The "when" section contains descriptions of the circumstances under which
+        # this task should be included in the task graph.  This will be converted
+        # into an optimization, so it cannot be specified in a job description that
+        # also gives 'optimization'.
+        Exclusive("when", "optimization"): Any(
+            None,
+            {
+                # This task only needs to be run if a file matching one of the given
+                # patterns has changed in the push.  The patterns use the mozpack
+                # match function (python/mozbuild/mozpack/path.py).
+                Optional("files-changed"): [str],
+            },
+        ),
+        # A list of artifacts to install from 'fetch' tasks.
+        Optional("fetches"): {
+            str: [
+                str,
+                {
+                    Required("artifact"): str,
+                    Optional("dest"): str,
+                    Optional("extract"): bool,
+                    Optional("verify-hash"): bool,
+                },
+            ],
+        },
+        # A description of how to run this job.
+        "run": {
+            # The key to a job implementation in a peer module to this one
+            "using": str,
+            # Base work directory used to set up the task.
+            Optional("workdir"): str,
+            # Any remaining content is verified against that job implementation's
+            # own schema.
+            Extra: object,
+        },
+        Required("worker-type"): task_description_schema["worker-type"],
+        # This object will be passed through to the task description, with additions
+        # provided by the job's run-using function
+        Optional("worker"): dict,
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(job_description_schema)
+
+
+@transforms.add
+def rewrite_when_to_optimization(config, jobs):
+    for job in jobs:
+        when = job.pop("when", {})
+        if not when:
+            yield job
+            continue
+
+        files_changed = when.get("files-changed")
+
+        # implicitly add task config directory.
+        files_changed.append(f"{config.path}/**")
+
+        # "only when files changed" implies "skip if files have not changed"
+        job["optimization"] = {"skip-unless-changed": files_changed}
+
+        assert "when" not in job
+        yield job
+
+
+@transforms.add
+def set_implementation(config, jobs):
+    for job in jobs:
+        impl, os = worker_type_implementation(
+            config.graph_config, config.params, job["worker-type"]
+        )
+        if os:
+            job.setdefault("tags", {})["os"] = os
+        if impl:
+            job.setdefault("tags", {})["worker-implementation"] = impl
+        worker = job.setdefault("worker", {})
+        assert "implementation" not in worker
+        worker["implementation"] = impl
+        if os:
+            worker["os"] = os
+        yield job
+
+
+@transforms.add
+def set_label(config, jobs):
+    for job in jobs:
+        if "label" not in job:
+            if "name" not in job:
+                raise Exception("job has neither a name nor a label")
+            job["label"] = "{}-{}".format(config.kind, job["name"])
+        if job.get("name"):
+            del job["name"]
+        yield job
+
+
+@transforms.add
+def add_resource_monitor(config, jobs):
+    for job in jobs:
+        if job.get("attributes", {}).get("resource-monitor"):
+            worker_implementation, worker_os = worker_type_implementation(
+                config.graph_config, config.params, job["worker-type"]
+            )
+            # Normalise worker os so that linux-bitbar and similar use linux tools.
+            worker_os = worker_os.split("-")[0]
+            # We don't currently support an Arm worker, due to gopsutil's indirect
+            # dependencies (go-ole)
+            if "aarch64" in job["worker-type"]:
+                yield job
+                continue
+            elif "win7" in job["worker-type"]:
+                arch = "32"
+            else:
+                arch = "64"
+            job.setdefault("fetches", {})
+            job["fetches"].setdefault("toolchain", [])
+            job["fetches"]["toolchain"].append(f"{worker_os}{arch}-resource-monitor")
+
+            if worker_implementation == "docker-worker":
+                artifact_source = "/builds/worker/monitoring/resource-monitor.json"
+            else:
+                artifact_source = "monitoring/resource-monitor.json"
+            job["worker"].setdefault("artifacts", [])
+            job["worker"]["artifacts"].append(
+                {
+                    "name": "public/monitoring/resource-monitor.json",
+                    "type": "file",
+                    "path": artifact_source,
+                }
+            )
+            # Set env for output file
+            job["worker"].setdefault("env", {})
+            job["worker"]["env"]["RESOURCE_MONITOR_OUTPUT"] = artifact_source
+
+        yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    """Given a build description, create a task description"""
+    # import plugin modules first, before iterating over jobs
+    import_sibling_modules(exceptions=("common.py",))
+
+    for job in jobs:
+        # only docker-worker uses a fixed absolute path to find directories
+        if job["worker"]["implementation"] == "docker-worker":
+            job["run"].setdefault("workdir", "/builds/worker")
+
+        taskdesc = copy_task(job)
+
+        # fill in some empty defaults to make run implementations easier
+        taskdesc.setdefault("attributes", {})
+        taskdesc.setdefault("dependencies", {})
+        taskdesc.setdefault("if-dependencies", [])
+        taskdesc.setdefault("soft-dependencies", [])
+        taskdesc.setdefault("routes", [])
+        taskdesc.setdefault("scopes", [])
+        taskdesc.setdefault("extra", {})
+
+        # give the function for job.run.using on this worker implementation a
+        # chance to set up the task description.
+        configure_taskdesc_for_run(
+            config, job, taskdesc, job["worker"]["implementation"]
+        )
+        del taskdesc["run"]
+
+        # yield only the task description, discarding the job description
+        yield taskdesc
+
+
+def get_attribute(dict, key, attributes, attribute_name):
+    """Get `attribute_name` from the given `attributes` dict, and if there
+    is a corresponding value, set `key` in `dict` to that value."""
+    value = attributes.get(attribute_name)
+    if value:
+        dict[key] = value
+
+
+@transforms.add
+def use_system_python(config, jobs):
+    for job in jobs:
+        if job.pop("use-system-python", True):
+            yield job
+        else:
+            fetches = job.setdefault("fetches", {})
+            toolchain = fetches.setdefault("toolchain", [])
+
+            moz_python_home = mozpath.join("fetches", "python")
+            if "win" in job["worker"]["os"]:
+                platform = "win64"
+            elif "linux" in job["worker"]["os"]:
+                platform = "linux64"
+            elif "macosx" in job["worker"]["os"]:
+                platform = "macosx64"
+            else:
+                raise ValueError("unexpected worker.os value {}".format(platform))
+
+            toolchain.append("{}-python".format(platform))
+
+            worker = job.setdefault("worker", {})
+            env = worker.setdefault("env", {})
+            env["MOZ_PYTHON_HOME"] = moz_python_home
+
+            yield job
+
+
+@transforms.add
+def use_fetches(config, jobs):
+    artifact_names = {}
+    extra_env = {}
+    aliases = {}
+    tasks = []
+
+    if config.kind in ("toolchain", "fetch"):
+        jobs = list(jobs)
+        tasks.extend((config.kind, j) for j in jobs)
+
+    tasks.extend(
+        (task.kind, task.__dict__)
+        for task in config.kind_dependencies_tasks.values()
+        if task.kind in ("fetch", "toolchain")
+    )
+    for (kind, task) in tasks:
+        get_attribute(
+            artifact_names, task["label"], task["attributes"], f"{kind}-artifact"
+        )
+        get_attribute(extra_env, task["label"], task["attributes"], f"{kind}-env")
+        value = task["attributes"].get(f"{kind}-alias")
+        if not value:
+            value = []
+        elif isinstance(value, str):
+            value = [value]
+        for alias in value:
+            fully_qualified = f"{kind}-{alias}"
+            label = task["label"]
+            if fully_qualified == label:
+                raise Exception(f"The alias {alias} of task {label} points to itself!")
+            aliases[fully_qualified] = label
+
+    artifact_prefixes = {}
+    for job in order_tasks(config, jobs):
+        artifact_prefixes[job["label"]] = get_artifact_prefix(job)
+
+        fetches = job.pop("fetches", None)
+        if not fetches:
+            yield job
+            continue
+
+        job_fetches = []
+        name = job.get("name") or job.get("label").replace(f"{config.kind}-", "")
+        dependencies = job.setdefault("dependencies", {})
+        worker = job.setdefault("worker", {})
+        env = worker.setdefault("env", {})
+        prefix = get_artifact_prefix(job)
+        has_sccache = False
+        for kind, artifacts in fetches.items():
+            if kind in ("fetch", "toolchain"):
+                for fetch_name in artifacts:
+                    label = f"{kind}-{fetch_name}"
+                    label = aliases.get(label, label)
+                    if label not in artifact_names:
+                        raise Exception(
+                            "Missing fetch job for {kind}-{name}: {fetch}".format(
+                                kind=config.kind, name=name, fetch=fetch_name
+                            )
+                        )
+                    if label in extra_env:
+                        env.update(extra_env[label])
+
+                    path = artifact_names[label]
+
+                    dependencies[label] = label
+                    job_fetches.append(
+                        {
+                            "artifact": path,
+                            "task": f"<{label}>",
+                            "extract": True,
+                        }
+                    )
+
+                    if kind == "toolchain" and fetch_name.endswith("-sccache"):
+                        has_sccache = True
+            else:
+                if kind not in dependencies:
+                    raise Exception(
+                        "{name} can't fetch {kind} artifacts because "
+                        "it has no {kind} dependencies!".format(name=name, kind=kind)
+                    )
+                dep_label = dependencies[kind]
+                if dep_label in artifact_prefixes:
+                    prefix = artifact_prefixes[dep_label]
+                else:
+                    if dep_label not in config.kind_dependencies_tasks:
+                        raise Exception(
+                            "{name} can't fetch {kind} artifacts because "
+                            "there are no tasks with label {label} in kind dependencies!".format(
+                                name=name,
+                                kind=kind,
+                                label=dependencies[kind],
+                            )
+                        )
+
+                    prefix = get_artifact_prefix(
+                        config.kind_dependencies_tasks[dep_label]
+                    )
+
+                for artifact in artifacts:
+                    if isinstance(artifact, str):
+                        path = artifact
+                        dest = None
+                        extract = True
+                        verify_hash = False
+                    else:
+                        path = artifact["artifact"]
+                        dest = artifact.get("dest")
+                        extract = artifact.get("extract", True)
+                        verify_hash = artifact.get("verify-hash", False)
+
+                    fetch = {
+                        "artifact": f"{prefix}/{path}"
+                        if not path.startswith("/")
+                        else path[1:],
+                        "task": f"<{kind}>",
+                        "extract": extract,
+                    }
+                    if dest is not None:
+                        fetch["dest"] = dest
+                    if verify_hash:
+                        fetch["verify-hash"] = verify_hash
+                    job_fetches.append(fetch)
+
+        if job.get("use-sccache") and not has_sccache:
+            raise Exception("Must provide an sccache toolchain if using sccache.")
+
+        job_artifact_prefixes = {
+            mozpath.dirname(fetch["artifact"])
+            for fetch in job_fetches
+            if not fetch["artifact"].startswith("public/")
+        }
+        if job_artifact_prefixes:
+            # Use taskcluster-proxy and request appropriate scope.  For example, add
+            # 'scopes: [queue:get-artifact:path/to/*]' for 'path/to/artifact.tar.xz'.
+            worker["taskcluster-proxy"] = True
+            for prefix in sorted(job_artifact_prefixes):
+                scope = f"queue:get-artifact:{prefix}/*"
+                if scope not in job.setdefault("scopes", []):
+                    job["scopes"].append(scope)
+
+        artifacts = {}
+        for f in job_fetches:
+            _, __, artifact = f["artifact"].rpartition("/")
+            if "dest" in f:
+                artifact = f"{f['dest']}/{artifact}"
+            task = f["task"][1:-1]
+            if artifact in artifacts:
+                raise Exception(
+                    f"Task {name} depends on {artifacts[artifact]} and {task} "
+                    f"that both provide {artifact}"
+                )
+            artifacts[artifact] = task
+
+        env["MOZ_FETCHES"] = {
+            "task-reference": json.dumps(
+                sorted(job_fetches, key=lambda x: sorted(x.items())), sort_keys=True
+            )
+        }
+        # The path is normalized to an absolute path in run-task
+        env.setdefault("MOZ_FETCHES_DIR", "fetches")
+
+        yield job
+
+
+# A registry of all functions decorated with run_job_using
+registry = {}
+
+
+def run_job_using(worker_implementation, run_using, schema=None, defaults={}):
+    """Register the decorated function as able to set up a task description for
+    jobs with the given worker implementation and `run.using` property.  If
+    `schema` is given, the job's run field will be verified to match it.
+
+    The decorated function should have the signature `using_foo(config, job, taskdesc)`
+    and should modify the task description in-place.  The skeleton of
+    the task description is already set up, but without a payload."""
+
+    def wrap(func):
+        for_run_using = registry.setdefault(run_using, {})
+        if worker_implementation in for_run_using:
+            raise Exception(
+                "run_job_using({!r}, {!r}) already exists: {!r}".format(
+                    run_using, worker_implementation, for_run_using[run_using]
+                )
+            )
+        for_run_using[worker_implementation] = (func, schema, defaults)
+        return func
+
+    return wrap
+
+
+@run_job_using(
+    "always-optimized", "always-optimized", Schema({"using": "always-optimized"})
+)
+def always_optimized(config, job, taskdesc):
+    pass
+
+
+def configure_taskdesc_for_run(config, job, taskdesc, worker_implementation):
+    """
+    Run the appropriate function for this job against the given task
+    description.
+
+    This will raise an appropriate error if no function exists, or if the job's
+    run is not valid according to the schema.
+    """
+    run_using = job["run"]["using"]
+    if run_using not in registry:
+        raise Exception(f"no functions for run.using {run_using!r}")
+
+    if worker_implementation not in registry[run_using]:
+        raise Exception(
+            "no functions for run.using {!r} on {!r}".format(
+                run_using, worker_implementation
+            )
+        )
+
+    func, schema, defaults = registry[run_using][worker_implementation]
+    for k, v in defaults.items():
+        job["run"].setdefault(k, v)
+
+    if schema:
+        validate_schema(
+            schema,
+            job["run"],
+            "In job.run using {!r}/{!r} for job {!r}:".format(
+                job["run"]["using"], worker_implementation, job["label"]
+            ),
+        )
+    func(config, job, taskdesc)
diff --git a/taskcluster/gecko_taskgraph/transforms/job/common.py b/taskcluster/gecko_taskgraph/transforms/job/common.py
new file mode 100644
index 0000000000..0c6289a6db
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/common.py
@@ -0,0 +1,269 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Common support for various job types.  These functions are all named after the
+worker implementation they operate on, and take the same three parameters, for
+consistency.
+"""
+
+
+from taskgraph.util.keyed_by import evaluate_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+
+SECRET_SCOPE = "secrets:get:project/releng/{trust_domain}/{kind}/level-{level}/{secret}"
+
+
+def add_cache(job, taskdesc, name, mount_point, skip_untrusted=False):
+    """Adds a cache based on the worker's implementation.
+
+    Args:
+        job (dict): Task's job description.
+        taskdesc (dict): Target task description to modify.
+        name (str): Name of the cache.
+        mount_point (path): Path on the host to mount the cache.
+        skip_untrusted (bool): Whether cache is used in untrusted environments
+            (default: False). Only applies to docker-worker.
+    """
+    if not job["run"].get("use-caches", True):
+        return
+
+    worker = job["worker"]
+
+    if worker["implementation"] == "docker-worker":
+        taskdesc["worker"].setdefault("caches", []).append(
+            {
+                "type": "persistent",
+                "name": name,
+                "mount-point": mount_point,
+                "skip-untrusted": skip_untrusted,
+            }
+        )
+
+    elif worker["implementation"] == "generic-worker":
+        taskdesc["worker"].setdefault("mounts", []).append(
+            {
+                "cache-name": name,
+                "directory": mount_point,
+            }
+        )
+
+    else:
+        # Caches not implemented
+        pass
+
+
+def add_artifacts(config, job, taskdesc, path):
+    taskdesc["worker"].setdefault("artifacts", []).append(
+        {
+            "name": get_artifact_prefix(taskdesc),
+            "path": path,
+            "type": "directory",
+        }
+    )
+
+
+def docker_worker_add_artifacts(config, job, taskdesc):
+    """Adds an artifact directory to the task"""
+    path = "{workdir}/artifacts/".format(**job["run"])
+    taskdesc["worker"].setdefault("env", {})["UPLOAD_DIR"] = path
+    add_artifacts(config, job, taskdesc, path)
+
+
+def generic_worker_add_artifacts(config, job, taskdesc):
+    """Adds an artifact directory to the task"""
+    # The path is the location on disk; it doesn't necessarily
+    # mean the artifacts will be public or private; that is set via the name
+    # attribute in add_artifacts.
+    path = get_artifact_prefix(taskdesc)
+    taskdesc["worker"].setdefault("env", {})["UPLOAD_DIR"] = path
+    add_artifacts(config, job, taskdesc, path=path)
+
+
+def support_vcs_checkout(config, job, taskdesc, sparse=False):
+    """Update a job/task with parameters to enable a VCS checkout.
+
+    This can only be used with ``run-task`` tasks, as the cache name is
+    reserved for ``run-task`` tasks.
+    """
+    worker = job["worker"]
+    is_mac = worker["os"] == "macosx"
+    is_win = worker["os"] == "windows"
+    is_linux = worker["os"] == "linux" or "linux-bitbar"
+    is_docker = worker["implementation"] == "docker-worker"
+    assert is_mac or is_win or is_linux
+
+    if is_win:
+        checkoutdir = "./build"
+        geckodir = f"{checkoutdir}/src"
+        hgstore = "y:/hg-shared"
+    elif is_docker:
+        checkoutdir = "{workdir}/checkouts".format(**job["run"])
+        geckodir = f"{checkoutdir}/gecko"
+        hgstore = f"{checkoutdir}/hg-store"
+    else:
+        checkoutdir = "./checkouts"
+        geckodir = f"{checkoutdir}/gecko"
+        hgstore = f"{checkoutdir}/hg-shared"
+
+    cache_name = "checkouts"
+
+    # Sparse checkouts need their own cache because they can interfere
+    # with clients that aren't sparse aware.
+    if sparse:
+        cache_name += "-sparse"
+
+    # Workers using Mercurial >= 5.8 will enable revlog-compression-zstd, which
+    # workers using older versions can't understand, so they can't share cache.
+    # At the moment, only docker workers use the newer version.
+    if is_docker:
+        cache_name += "-hg58"
+
+    add_cache(job, taskdesc, cache_name, checkoutdir)
+
+    taskdesc["worker"].setdefault("env", {}).update(
+        {
+            "GECKO_BASE_REPOSITORY": config.params["base_repository"],
+            "GECKO_HEAD_REPOSITORY": config.params["head_repository"],
+            "GECKO_HEAD_REV": config.params["head_rev"],
+            "HG_STORE_PATH": hgstore,
+        }
+    )
+    taskdesc["worker"]["env"].setdefault("GECKO_PATH", geckodir)
+
+    if "comm_base_repository" in config.params:
+        taskdesc["worker"]["env"].update(
+            {
+                "COMM_BASE_REPOSITORY": config.params["comm_base_repository"],
+                "COMM_HEAD_REPOSITORY": config.params["comm_head_repository"],
+                "COMM_HEAD_REV": config.params["comm_head_rev"],
+            }
+        )
+    elif job["run"].get("comm-checkout", False):
+        raise Exception(
+            "Can't checkout from comm-* repository if not given a repository."
+        )
+
+    # Give task access to hgfingerprint secret so it can pin the certificate
+    # for hg.mozilla.org.
+    taskdesc["scopes"].append("secrets:get:project/taskcluster/gecko/hgfingerprint")
+    taskdesc["scopes"].append("secrets:get:project/taskcluster/gecko/hgmointernal")
+
+    # only some worker platforms have taskcluster-proxy enabled
+    if job["worker"]["implementation"] in ("docker-worker",):
+        taskdesc["worker"]["taskcluster-proxy"] = True
+
+
+def generic_worker_hg_commands(
+    base_repo, head_repo, head_rev, path, sparse_profile=None
+):
+    """Obtain commands needed to obtain a Mercurial checkout on generic-worker.
+
+    Returns two command strings. One performs the checkout. Another logs.
+    """
+    args = [
+        r'"c:\Program Files\Mercurial\hg.exe"',
+        "robustcheckout",
+        "--sharebase",
+        r"y:\hg-shared",
+        "--purge",
+        "--upstream",
+        base_repo,
+        "--revision",
+        head_rev,
+    ]
+
+    if sparse_profile:
+        args.extend(["--config", "extensions.sparse="])
+        args.extend(["--sparseprofile", sparse_profile])
+
+    args.extend(
+        [
+            head_repo,
+            path,
+        ]
+    )
+
+    logging_args = [
+        b":: TinderboxPrint:<a href={source_repo}/rev/{revision} "
+        b"title='Built from {repo_name} revision {revision}'>{revision}</a>"
+        b"\n".format(
+            revision=head_rev, source_repo=head_repo, repo_name=head_repo.split("/")[-1]
+        ),
+    ]
+
+    return [" ".join(args), " ".join(logging_args)]
+
+
+def setup_secrets(config, job, taskdesc):
+    """Set up access to secrets via taskcluster-proxy.  The value of
+    run['secrets'] should be a boolean or a list of secret names that
+    can be accessed."""
+    if not job["run"].get("secrets"):
+        return
+
+    taskdesc["worker"]["taskcluster-proxy"] = True
+    secrets = job["run"]["secrets"]
+    if secrets is True:
+        secrets = ["*"]
+    for secret in secrets:
+        taskdesc["scopes"].append(
+            SECRET_SCOPE.format(
+                trust_domain=config.graph_config["trust-domain"],
+                kind=job["treeherder"]["kind"],
+                level=config.params["level"],
+                secret=secret,
+            )
+        )
+
+
+def add_tooltool(config, job, taskdesc, internal=False):
+    """Give the task access to tooltool.
+
+    Enables the tooltool cache. Adds releng proxy. Configures scopes.
+
+    By default, only public tooltool access will be granted. Access to internal
+    tooltool can be enabled via ``internal=True``.
+
+    This can only be used with ``run-task`` tasks, as the cache name is
+    reserved for use with ``run-task``.
+    """
+
+    if job["worker"]["implementation"] in ("docker-worker",):
+        add_cache(
+            job,
+            taskdesc,
+            "tooltool-cache",
+            "{workdir}/tooltool-cache".format(**job["run"]),
+        )
+
+        taskdesc["worker"].setdefault("env", {}).update(
+            {
+                "TOOLTOOL_CACHE": "{workdir}/tooltool-cache".format(**job["run"]),
+            }
+        )
+    elif not internal:
+        return
+
+    taskdesc["worker"]["taskcluster-proxy"] = True
+    taskdesc["scopes"].extend(
+        [
+            "project:releng:services/tooltool/api/download/public",
+        ]
+    )
+
+    if internal:
+        taskdesc["scopes"].extend(
+            [
+                "project:releng:services/tooltool/api/download/internal",
+            ]
+        )
+
+
+def get_expiration(config, policy="default"):
+    expires = evaluate_keyed_by(
+        config.graph_config["expiration-policy"],
+        "artifact expiration",
+        {"project": config.params["project"]},
+    )[policy]
+    return expires
diff --git a/taskcluster/gecko_taskgraph/transforms/job/distro_package.py b/taskcluster/gecko_taskgraph/transforms/job/distro_package.py
new file mode 100644
index 0000000000..44236b1abc
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/distro_package.py
@@ -0,0 +1,238 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running spidermonkey jobs via dedicated scripts
+"""
+
+
+import os
+import re
+
+import taskgraph
+from taskgraph.util.schema import Schema
+from taskgraph.util.taskcluster import get_root_url
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.transforms.job import run_job_using
+from gecko_taskgraph.transforms.job.common import add_artifacts
+from gecko_taskgraph.util.hash import hash_path
+
+DSC_PACKAGE_RE = re.compile(".*(?=_)")
+SOURCE_PACKAGE_RE = re.compile(r".*(?=[-_]\d)")
+
+source_definition = {
+    Required("url"): str,
+    Required("sha256"): str,
+}
+
+common_schema = Schema(
+    {
+        # URL/SHA256 of a source file to build, which can either be a source
+        # control (.dsc), or a tarball.
+        Required(Any("dsc", "tarball")): source_definition,
+        # Package name. Normally derived from the source control or tarball file
+        # name. Use in case the name doesn't match DSC_PACKAGE_RE or
+        # SOURCE_PACKAGE_RE.
+        Optional("name"): str,
+        # Patch to apply to the extracted source.
+        Optional("patch"): str,
+        # Command to run before dpkg-buildpackage.
+        Optional("pre-build-command"): str,
+        # Architecture to build the package for.
+        Optional("arch"): str,
+        # List of package tasks to get build dependencies from.
+        Optional("packages"): [str],
+        # What resolver to use to install build dependencies. The default
+        # (apt-get) is good in most cases, but in subtle cases involving
+        # a *-backports archive, its solver might not be able to find a
+        # solution that satisfies the build dependencies.
+        Optional("resolver"): Any("apt-get", "aptitude"),
+        # Base work directory used to set up the task.
+        Required("workdir"): str,
+    }
+)
+
+debian_schema = common_schema.extend(
+    {
+        Required("using"): "debian-package",
+        # Debian distribution
+        Required("dist"): str,
+    }
+)
+
+ubuntu_schema = common_schema.extend(
+    {
+        Required("using"): "ubuntu-package",
+        # Ubuntu distribution
+        Required("dist"): str,
+    }
+)
+
+
+def common_package(config, job, taskdesc, distro, version):
+    run = job["run"]
+
+    name = taskdesc["label"].replace(f"{config.kind}-", "", 1)
+
+    arch = run.get("arch", "amd64")
+
+    worker = taskdesc["worker"]
+    worker.setdefault("artifacts", [])
+
+    image = "%s%d" % (distro, version)
+    if arch != "amd64":
+        image += "-" + arch
+    image += "-packages"
+    worker["docker-image"] = {"in-tree": image}
+
+    add_artifacts(config, job, taskdesc, path="/tmp/artifacts")
+
+    env = worker.setdefault("env", {})
+    env["DEBFULLNAME"] = "Mozilla build team"
+    env["DEBEMAIL"] = "dev-builds@lists.mozilla.org"
+
+    if "dsc" in run:
+        src = run["dsc"]
+        unpack = "dpkg-source -x {src_file} {package}"
+        package_re = DSC_PACKAGE_RE
+    elif "tarball" in run:
+        src = run["tarball"]
+        unpack = (
+            "mkdir {package} && "
+            "tar -C {package} -axf {src_file} --strip-components=1"
+        )
+        package_re = SOURCE_PACKAGE_RE
+    else:
+        raise RuntimeError("Unreachable")
+    src_url = src["url"]
+    src_file = os.path.basename(src_url)
+    src_sha256 = src["sha256"]
+    package = run.get("name")
+    if not package:
+        package = package_re.match(src_file).group(0)
+    unpack = unpack.format(src_file=src_file, package=package)
+
+    resolver = run.get("resolver", "apt-get")
+    if resolver == "apt-get":
+        resolver = "apt-get -yyq --no-install-recommends"
+    elif resolver == "aptitude":
+        resolver = (
+            "aptitude -y --without-recommends -o "
+            "Aptitude::ProblemResolver::Hints::KeepBuildDeps="
+            '"reject {}-build-deps :UNINST"'
+        ).format(package)
+    else:
+        raise RuntimeError("Unreachable")
+
+    adjust = ""
+    if "patch" in run:
+        # We don't use robustcheckout or run-task to get a checkout. So for
+        # this one file we'd need from a checkout, download it.
+        env["PATCH_URL"] = config.params.file_url(
+            "build/debian-packages/{patch}".format(patch=run["patch"]),
+        )
+        adjust += "curl -sL $PATCH_URL | patch -p1 && "
+    if "pre-build-command" in run:
+        adjust += run["pre-build-command"] + " && "
+    if "tarball" in run:
+        adjust += "mv ../{src_file} ../{package}_{ver}.orig.tar.gz && ".format(
+            src_file=src_file,
+            package=package,
+            ver="$(dpkg-parsechangelog | awk '$1==\"Version:\"{print $2}' | cut -f 1 -d -)",
+        )
+    if "patch" not in run and "pre-build-command" not in run:
+        adjust += (
+            'debchange -l ".{prefix}moz" --distribution "{dist}"'
+            ' "Mozilla backport for {dist}." < /dev/null && '
+        ).format(
+            prefix=name.split("-", 1)[0],
+            dist=run["dist"],
+        )
+
+    worker["command"] = [
+        "sh",
+        "-x",
+        "-c",
+        # Add sources for packages coming from other package tasks.
+        "/usr/local/sbin/setup_packages.sh {root_url} $PACKAGES && "
+        "apt-get update && "
+        # Upgrade packages that might have new versions in package tasks.
+        "apt-get dist-upgrade && " "cd /tmp && "
+        # Get, validate and extract the package source.
+        "(dget -d -u {src_url} || exit 100) && "
+        'echo "{src_sha256}  {src_file}" | sha256sum -c && '
+        "{unpack} && "
+        "cd {package} && "
+        # Optionally apply patch and/or pre-build command.
+        "{adjust}"
+        # Install the necessary build dependencies.
+        "(cd ..; mk-build-deps -i -r {package}/debian/control -t '{resolver}' || exit 100) && "
+        # Build the package
+        'DEB_BUILD_OPTIONS="parallel=$(nproc) nocheck" dpkg-buildpackage -sa && '
+        # Copy the artifacts
+        "mkdir -p {artifacts}/apt && "
+        "dcmd cp ../{package}_*.changes {artifacts}/apt/ && "
+        "cd {artifacts} && "
+        # Make the artifacts directory usable as an APT repository.
+        "apt-ftparchive sources apt | gzip -c9 > apt/Sources.gz && "
+        "apt-ftparchive packages apt | gzip -c9 > apt/Packages.gz".format(
+            root_url=get_root_url(False),
+            package=package,
+            src_url=src_url,
+            src_file=src_file,
+            src_sha256=src_sha256,
+            unpack=unpack,
+            adjust=adjust,
+            artifacts="/tmp/artifacts",
+            resolver=resolver,
+        ),
+    ]
+
+    if run.get("packages"):
+        env = worker.setdefault("env", {})
+        env["PACKAGES"] = {
+            "task-reference": " ".join(f"<{p}>" for p in run["packages"])
+        }
+        deps = taskdesc.setdefault("dependencies", {})
+        for p in run["packages"]:
+            deps[p] = f"packages-{p}"
+
+    # Use the command generated above as the base for the index hash.
+    # We rely on it not varying depending on the head_repository or head_rev.
+    digest_data = list(worker["command"])
+    if "patch" in run:
+        digest_data.append(
+            hash_path(os.path.join(GECKO, "build", "debian-packages", run["patch"]))
+        )
+
+    if not taskgraph.fast:
+        taskdesc["cache"] = {
+            "type": "packages.v1",
+            "name": name,
+            "digest-data": digest_data,
+        }
+
+
+@run_job_using("docker-worker", "debian-package", schema=debian_schema)
+def docker_worker_debian_package(config, job, taskdesc):
+    run = job["run"]
+    version = {
+        "wheezy": 7,
+        "jessie": 8,
+        "stretch": 9,
+        "buster": 10,
+        "bullseye": 11,
+    }[run["dist"]]
+    common_package(config, job, taskdesc, "debian", version)
+
+
+@run_job_using("docker-worker", "ubuntu-package", schema=ubuntu_schema)
+def docker_worker_ubuntu_package(config, job, taskdesc):
+    run = job["run"]
+    version = {
+        "bionic": 1804,
+        "focal": 2004,
+    }[run["dist"]]
+    common_package(config, job, taskdesc, "ubuntu", version)
diff --git a/taskcluster/gecko_taskgraph/transforms/job/hazard.py b/taskcluster/gecko_taskgraph/transforms/job/hazard.py
new file mode 100644
index 0000000000..af0e8616e0
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/hazard.py
@@ -0,0 +1,66 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running hazard jobs via dedicated scripts
+"""
+
+
+from taskgraph.util.schema import Schema
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+from gecko_taskgraph.transforms.job.common import (
+    add_tooltool,
+    docker_worker_add_artifacts,
+    setup_secrets,
+)
+
+haz_run_schema = Schema(
+    {
+        Required("using"): "hazard",
+        # The command to run within the task image (passed through to the worker)
+        Required("command"): str,
+        # The mozconfig to use; default in the script is used if omitted
+        Optional("mozconfig"): str,
+        # The set of secret names to which the task has access; these are prefixed
+        # with `project/releng/gecko/{treeherder.kind}/level-{level}/`.   Setting
+        # this will enable any worker features required and set the task's scopes
+        # appropriately.  `true` here means ['*'], all secrets.  Not supported on
+        # Windows
+        Optional("secrets"): Any(bool, [str]),
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+    }
+)
+
+
+@run_job_using("docker-worker", "hazard", schema=haz_run_schema)
+def docker_worker_hazard(config, job, taskdesc):
+    run = job["run"]
+
+    worker = taskdesc["worker"] = job["worker"]
+    worker.setdefault("artifacts", [])
+
+    docker_worker_add_artifacts(config, job, taskdesc)
+    worker.setdefault("required-volumes", []).append(
+        "{workdir}/workspace".format(**run)
+    )
+    add_tooltool(config, job, taskdesc)
+    setup_secrets(config, job, taskdesc)
+
+    env = worker["env"]
+    env.update(
+        {
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+        }
+    )
+
+    # script parameters
+    if run.get("mozconfig"):
+        env["MOZCONFIG"] = run.pop("mozconfig")
+
+    run["using"] = "run-task"
+    run["cwd"] = run["workdir"]
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
diff --git a/taskcluster/gecko_taskgraph/transforms/job/mach.py b/taskcluster/gecko_taskgraph/transforms/job/mach.py
new file mode 100644
index 0000000000..a418b44794
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/mach.py
@@ -0,0 +1,83 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running mach tasks (via run-task)
+"""
+
+from taskgraph.util.schema import Schema, taskref_or_string
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+
+mach_schema = Schema(
+    {
+        Required("using"): "mach",
+        # The mach command (omitting `./mach`) to run
+        Required("mach"): taskref_or_string,
+        # The version of Python to run with. Either an absolute path to the binary
+        # on the worker, a version identifier (e.g python2.7 or 3.8). There is no
+        # validation performed to ensure the specified binaries actually exist.
+        Optional("python-version"): Any(str, int, float),
+        # The sparse checkout profile to use. Value is the filename relative to the
+        # directory where sparse profiles are defined (build/sparse-profiles/).
+        Optional("sparse-profile"): Any(str, None),
+        # if true, perform a checkout of a comm-central based branch inside the
+        # gecko checkout
+        Required("comm-checkout"): bool,
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+        # Context to substitute into the command using format string
+        # substitution (e.g {value}). This is useful if certain aspects of the
+        # command need to be generated in transforms.
+        Optional("command-context"): dict,
+    }
+)
+
+
+defaults = {
+    "comm-checkout": False,
+}
+
+
+@run_job_using("docker-worker", "mach", schema=mach_schema, defaults=defaults)
+@run_job_using("generic-worker", "mach", schema=mach_schema, defaults=defaults)
+def configure_mach(config, job, taskdesc):
+    run = job["run"]
+    worker = job["worker"]
+
+    additional_prefix = []
+    if worker["os"] == "macosx":
+        additional_prefix = ["LC_ALL=en_US.UTF-8", "LANG=en_US.UTF-8"]
+
+    python = run.get("python-version")
+    if python:
+        del run["python-version"]
+
+        if worker["os"] == "macosx" and python == 3:
+            python = "/usr/local/bin/python3"
+
+        python = str(python)
+        try:
+            float(python)
+            python = "python" + python
+        except ValueError:
+            pass
+
+        additional_prefix.append(python)
+
+    command_prefix = " ".join(additional_prefix + ["./mach "])
+
+    mach = run["mach"]
+    if isinstance(mach, dict):
+        ref, pattern = next(iter(mach.items()))
+        command = {ref: command_prefix + pattern}
+    else:
+        command = command_prefix + mach
+
+    # defer to the run_task implementation
+    run["command"] = command
+    run["cwd"] = "{checkout}"
+    run["using"] = "run-task"
+    del run["mach"]
+    configure_taskdesc_for_run(config, job, taskdesc, job["worker"]["implementation"])
diff --git a/taskcluster/gecko_taskgraph/transforms/job/mozharness.py b/taskcluster/gecko_taskgraph/transforms/job/mozharness.py
new file mode 100644
index 0000000000..3dbcc6e015
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/mozharness.py
@@ -0,0 +1,366 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+
+Support for running jobs via mozharness.  Ideally, most stuff gets run this
+way, and certainly anything using mozharness should use this approach.
+
+"""
+
+import json
+from textwrap import dedent
+
+from mozpack import path as mozpath
+from taskgraph.util.schema import Schema
+from voluptuous import Any, Optional, Required
+from voluptuous.validators import Match
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+from gecko_taskgraph.transforms.job.common import (
+    docker_worker_add_artifacts,
+    generic_worker_add_artifacts,
+    get_expiration,
+    setup_secrets,
+)
+from gecko_taskgraph.transforms.task import get_branch_repo, get_branch_rev
+from gecko_taskgraph.util.attributes import is_try
+
+mozharness_run_schema = Schema(
+    {
+        Required("using"): "mozharness",
+        # the mozharness script used to run this task, relative to the testing/
+        # directory and using forward slashes even on Windows
+        Required("script"): str,
+        # Additional paths to look for mozharness configs in. These should be
+        # relative to the base of the source checkout
+        Optional("config-paths"): [str],
+        # the config files required for the task, relative to
+        # testing/mozharness/configs or one of the paths specified in
+        # `config-paths` and using forward slashes even on Windows
+        Required("config"): [str],
+        # any additional actions to pass to the mozharness command
+        Optional("actions"): [
+            Match("^[a-z0-9-]+$", "actions must be `-` seperated alphanumeric strings")
+        ],
+        # any additional options (without leading --) to be passed to mozharness
+        Optional("options"): [
+            Match(
+                "^[a-z0-9-]+(=[^ ]+)?$",
+                "options must be `-` seperated alphanumeric strings (with optional argument)",
+            )
+        ],
+        # --custom-build-variant-cfg value
+        Optional("custom-build-variant-cfg"): str,
+        # Extra configuration options to pass to mozharness.
+        Optional("extra-config"): dict,
+        # If not false, tooltool downloads will be enabled via relengAPIProxy
+        # for either just public files, or all files.  Not supported on Windows
+        Required("tooltool-downloads"): Any(
+            False,
+            "public",
+            "internal",
+        ),
+        # The set of secret names to which the task has access; these are prefixed
+        # with `project/releng/gecko/{treeherder.kind}/level-{level}/`.  Setting
+        # this will enable any worker features required and set the task's scopes
+        # appropriately.  `true` here means ['*'], all secrets.  Not supported on
+        # Windows
+        Required("secrets"): Any(bool, [str]),
+        # If true, taskcluster proxy will be enabled; note that it may also be enabled
+        # automatically e.g., for secrets support.  Not supported on Windows.
+        Required("taskcluster-proxy"): bool,
+        # If false, indicate that builds should skip producing artifacts.  Not
+        # supported on Windows.
+        Required("keep-artifacts"): bool,
+        # If specified, use the in-tree job script specified.
+        Optional("job-script"): str,
+        Required("requires-signed-builds"): bool,
+        # Whether or not to use caches.
+        Optional("use-caches"): bool,
+        # If false, don't set MOZ_SIMPLE_PACKAGE_NAME
+        # Only disableable on windows
+        Required("use-simple-package"): bool,
+        # If false don't pass --branch mozharness script
+        # Only disableable on windows
+        Required("use-magic-mh-args"): bool,
+        # if true, perform a checkout of a comm-central based branch inside the
+        # gecko checkout
+        Required("comm-checkout"): bool,
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+        Optional("run-as-root"): bool,
+    }
+)
+
+
+mozharness_defaults = {
+    "tooltool-downloads": False,
+    "secrets": False,
+    "taskcluster-proxy": False,
+    "keep-artifacts": True,
+    "requires-signed-builds": False,
+    "use-simple-package": True,
+    "use-magic-mh-args": True,
+    "comm-checkout": False,
+    "run-as-root": False,
+}
+
+
+@run_job_using(
+    "docker-worker",
+    "mozharness",
+    schema=mozharness_run_schema,
+    defaults=mozharness_defaults,
+)
+def mozharness_on_docker_worker_setup(config, job, taskdesc):
+    run = job["run"]
+
+    worker = taskdesc["worker"] = job["worker"]
+
+    if not run.pop("use-simple-package", None):
+        raise NotImplementedError(
+            "Simple packaging cannot be disabled via"
+            "'use-simple-package' on docker-workers"
+        )
+    if not run.pop("use-magic-mh-args", None):
+        raise NotImplementedError(
+            "Cannot disabled mh magic arg passing via"
+            "'use-magic-mh-args' on docker-workers"
+        )
+
+    # Running via mozharness assumes an image that contains build.sh:
+    # by default, debian11-amd64-build, but it could be another image (like
+    # android-build).
+    worker.setdefault("docker-image", {"in-tree": "debian11-amd64-build"})
+
+    worker.setdefault("artifacts", []).append(
+        {
+            "name": "public/logs",
+            "path": "{workdir}/logs/".format(**run),
+            "type": "directory",
+            "expires-after": get_expiration(config, "medium"),
+        }
+    )
+    worker["taskcluster-proxy"] = run.pop("taskcluster-proxy", None)
+    docker_worker_add_artifacts(config, job, taskdesc)
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "WORKSPACE": "{workdir}/workspace".format(**run),
+            "MOZHARNESS_CONFIG": " ".join(run.pop("config")),
+            "MOZHARNESS_SCRIPT": run.pop("script"),
+            "MH_BRANCH": config.params["project"],
+            "MOZ_SOURCE_CHANGESET": get_branch_rev(config),
+            "MOZ_SOURCE_REPO": get_branch_repo(config),
+            "MH_BUILD_POOL": "taskcluster",
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+            "PYTHONUNBUFFERED": "1",
+        }
+    )
+
+    worker.setdefault("required-volumes", []).append(env["WORKSPACE"])
+
+    if "actions" in run:
+        env["MOZHARNESS_ACTIONS"] = " ".join(run.pop("actions"))
+
+    if "options" in run:
+        env["MOZHARNESS_OPTIONS"] = " ".join(run.pop("options"))
+
+    if "config-paths" in run:
+        env["MOZHARNESS_CONFIG_PATHS"] = " ".join(run.pop("config-paths"))
+
+    if "custom-build-variant-cfg" in run:
+        env["MH_CUSTOM_BUILD_VARIANT_CFG"] = run.pop("custom-build-variant-cfg")
+
+    extra_config = run.pop("extra-config", {})
+    extra_config["objdir"] = "obj-build"
+    env["EXTRA_MOZHARNESS_CONFIG"] = json.dumps(extra_config, sort_keys=True)
+
+    if "job-script" in run:
+        env["JOB_SCRIPT"] = run["job-script"]
+
+    if is_try(config.params):
+        env["TRY_COMMIT_MSG"] = config.params["message"]
+
+    # if we're not keeping artifacts, set some env variables to empty values
+    # that will cause the build process to skip copying the results to the
+    # artifacts directory.  This will have no effect for operations that are
+    # not builds.
+    if not run.pop("keep-artifacts"):
+        env["DIST_TARGET_UPLOADS"] = ""
+        env["DIST_UPLOADS"] = ""
+
+    # Retry if mozharness returns TBPL_RETRY
+    worker["retry-exit-status"] = [4]
+
+    setup_secrets(config, job, taskdesc)
+
+    run["using"] = "run-task"
+    run["command"] = mozpath.join(
+        "${GECKO_PATH}",
+        run.pop("job-script", "taskcluster/scripts/builder/build-linux.sh"),
+    )
+    run.pop("secrets")
+    run.pop("requires-signed-builds")
+
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
+
+
+@run_job_using(
+    "generic-worker",
+    "mozharness",
+    schema=mozharness_run_schema,
+    defaults=mozharness_defaults,
+)
+def mozharness_on_generic_worker(config, job, taskdesc):
+    assert job["worker"]["os"] in (
+        "windows",
+        "macosx",
+    ), "only supports windows and macOS right now: {}".format(job["label"])
+
+    run = job["run"]
+
+    # fail if invalid run options are included
+    invalid = []
+    if not run.pop("keep-artifacts", True):
+        invalid.append("keep-artifacts")
+    if invalid:
+        raise Exception(
+            "Jobs run using mozharness on Windows do not support properties "
+            + ", ".join(invalid)
+        )
+
+    worker = taskdesc["worker"] = job["worker"]
+
+    worker["taskcluster-proxy"] = run.pop("taskcluster-proxy", None)
+
+    setup_secrets(config, job, taskdesc)
+
+    taskdesc["worker"].setdefault("artifacts", []).append(
+        {
+            "name": "public/logs",
+            "path": "logs",
+            "type": "directory",
+            "expires-after": get_expiration(config, "medium"),
+        }
+    )
+
+    if not worker.get("skip-artifacts", False):
+        generic_worker_add_artifacts(config, job, taskdesc)
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+            "MH_BRANCH": config.params["project"],
+            "MOZ_SOURCE_CHANGESET": get_branch_rev(config),
+            "MOZ_SOURCE_REPO": get_branch_repo(config),
+        }
+    )
+    if run.pop("use-simple-package"):
+        env.update({"MOZ_SIMPLE_PACKAGE_NAME": "target"})
+
+    extra_config = run.pop("extra-config", {})
+    extra_config["objdir"] = "obj-build"
+    env["EXTRA_MOZHARNESS_CONFIG"] = json.dumps(extra_config, sort_keys=True)
+
+    # The windows generic worker uses batch files to pass environment variables
+    # to commands.  Setting a variable to empty in a batch file unsets, so if
+    # there is no `TRY_COMMIT_MESSAGE`, pass a space instead, so that
+    # mozharness doesn't try to find the commit message on its own.
+    if is_try(config.params):
+        env["TRY_COMMIT_MSG"] = config.params["message"] or "no commit message"
+
+    if not job["attributes"]["build_platform"].startswith(("win", "macosx")):
+        raise Exception(
+            "Task generation for mozharness build jobs currently only supported on "
+            "Windows and macOS"
+        )
+
+    mh_command = []
+    if job["worker"]["os"] == "windows":
+        system_python_dir = "c:/mozilla-build/python3/"
+        gecko_path = "%GECKO_PATH%"
+    else:
+        system_python_dir = ""
+        gecko_path = "$GECKO_PATH"
+
+    if run.get("use-system-python", True):
+        python_bindir = system_python_dir
+    else:
+        # $MOZ_PYTHON_HOME is going to be substituted in run-task, when we
+        # know the actual MOZ_PYTHON_HOME value.
+        is_windows = job["worker"]["os"] == "windows"
+        if is_windows:
+            python_bindir = "%MOZ_PYTHON_HOME%/"
+        else:
+            python_bindir = "${MOZ_PYTHON_HOME}/bin/"
+
+    mh_command = ["{}python3".format(python_bindir)]
+
+    mh_command += [
+        f"{gecko_path}/mach",
+        "python",
+        "{}/testing/{}".format(gecko_path, run.pop("script")),
+    ]
+
+    for path in run.pop("config-paths", []):
+        mh_command.append(f"--extra-config-path {gecko_path}/{path}")
+
+    for cfg in run.pop("config"):
+        mh_command.extend(("--config", cfg))
+    if run.pop("use-magic-mh-args"):
+        mh_command.extend(("--branch", config.params["project"]))
+    if job["worker"]["os"] == "windows":
+        mh_command.extend(("--work-dir", r"%cd:Z:=z:%\workspace"))
+    for action in run.pop("actions", []):
+        mh_command.append("--" + action)
+
+    for option in run.pop("options", []):
+        mh_command.append("--" + option)
+    if run.get("custom-build-variant-cfg"):
+        mh_command.append("--custom-build-variant")
+        mh_command.append(run.pop("custom-build-variant-cfg"))
+
+    if job["worker"]["os"] == "macosx":
+        # Ideally, we'd use shellutil.quote, but that would single-quote
+        # $GECKO_PATH, which would defeat having the variable in the command
+        # in the first place, as it wouldn't be expanded.
+        # In practice, arguments are expected not to contain characters that
+        # would require quoting.
+        mh_command = " ".join(mh_command)
+
+    run["using"] = "run-task"
+    run["command"] = mh_command
+    run.pop("secrets")
+    run.pop("requires-signed-builds")
+    run.pop("job-script", None)
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
+
+    # Everything past this point is Windows-specific.
+    if job["worker"]["os"] == "macosx":
+        return
+
+    if taskdesc.get("use-sccache"):
+        worker["command"] = (
+            [
+                # Make the comment part of the first command, as it will help users to
+                # understand what is going on, and why these steps are implemented.
+                dedent(
+                    """\
+            :: sccache currently uses the full compiler commandline as input to the
+            :: cache hash key, so create a symlink to the task dir and build from
+            :: the symlink dir to get consistent paths.
+            if exist z:\\build rmdir z:\\build"""
+                ),
+                r"mklink /d z:\build %cd%",
+                # Grant delete permission on the link to everyone.
+                r"icacls z:\build /grant *S-1-1-0:D /L",
+                r"cd /d z:\build",
+            ]
+            + worker["command"]
+        )
diff --git a/taskcluster/gecko_taskgraph/transforms/job/mozharness_test.py b/taskcluster/gecko_taskgraph/transforms/job/mozharness_test.py
new file mode 100644
index 0000000000..eb4aea609f
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/mozharness_test.py
@@ -0,0 +1,477 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+import re
+
+from taskgraph.util.schema import Schema
+from taskgraph.util.taskcluster import get_artifact_path, get_artifact_url
+from voluptuous import Extra, Optional, Required
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+from gecko_taskgraph.transforms.job.common import get_expiration, support_vcs_checkout
+from gecko_taskgraph.transforms.test import normpath, test_description_schema
+from gecko_taskgraph.util.attributes import is_try
+
+VARIANTS = [
+    "shippable",
+    "shippable-qr",
+    "shippable-lite",
+    "shippable-lite-qr",
+    "devedition",
+    "pgo",
+    "asan",
+    "stylo",
+    "qr",
+    "ccov",
+]
+
+
+def get_variant(test_platform):
+    for v in VARIANTS:
+        if f"-{v}/" in test_platform:
+            return v
+    return ""
+
+
+mozharness_test_run_schema = Schema(
+    {
+        Required("using"): "mozharness-test",
+        Required("test"): {
+            Required("test-platform"): str,
+            Required("mozharness"): test_description_schema["mozharness"],
+            Required("docker-image"): test_description_schema["docker-image"],
+            Required("loopback-video"): test_description_schema["loopback-video"],
+            Required("loopback-audio"): test_description_schema["loopback-audio"],
+            Required("max-run-time"): test_description_schema["max-run-time"],
+            Optional("retry-exit-status"): test_description_schema["retry-exit-status"],
+            Extra: object,
+        },
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+    }
+)
+
+
+def test_packages_url(taskdesc):
+    """Account for different platforms that name their test packages differently"""
+    artifact_url = get_artifact_url(
+        "<build>", get_artifact_path(taskdesc, "target.test_packages.json")
+    )
+    # for android shippable we need to add 'en-US' to the artifact url
+    test = taskdesc["run"]["test"]
+    if "android" in test["test-platform"] and (
+        get_variant(test["test-platform"])
+        in ("shippable", "shippable-qr", "shippable-lite", "shippable-lite-qr")
+    ):
+        head, tail = os.path.split(artifact_url)
+        artifact_url = os.path.join(head, "en-US", tail)
+    return artifact_url
+
+
+def installer_url(taskdesc):
+    test = taskdesc["run"]["test"]
+    mozharness = test["mozharness"]
+
+    if "installer-url" in mozharness:
+        installer_url = mozharness["installer-url"]
+    else:
+        upstream_task = (
+            "<build-signing>" if mozharness["requires-signed-builds"] else "<build>"
+        )
+        installer_url = get_artifact_url(
+            upstream_task, mozharness["build-artifact-name"]
+        )
+
+    return installer_url
+
+
+@run_job_using("docker-worker", "mozharness-test", schema=mozharness_test_run_schema)
+def mozharness_test_on_docker(config, job, taskdesc):
+    run = job["run"]
+    test = taskdesc["run"]["test"]
+    mozharness = test["mozharness"]
+    worker = taskdesc["worker"] = job["worker"]
+
+    # apply some defaults
+    worker["docker-image"] = test["docker-image"]
+    worker["allow-ptrace"] = True  # required for all tests, for crashreporter
+    worker["loopback-video"] = test["loopback-video"]
+    worker["loopback-audio"] = test["loopback-audio"]
+    worker["max-run-time"] = test["max-run-time"]
+    worker["retry-exit-status"] = test["retry-exit-status"]
+    if "android-em-7.0-x86" in test["test-platform"]:
+        worker["privileged"] = True
+
+    artifacts = [
+        # (artifact name prefix, in-image path)
+        ("public/logs", "{workdir}/workspace/logs/".format(**run)),
+        ("public/test", "{workdir}/artifacts/".format(**run)),
+        (
+            "public/test_info",
+            "{workdir}/workspace/build/blobber_upload_dir/".format(**run),
+        ),
+    ]
+
+    installer = installer_url(taskdesc)
+
+    mozharness_url = get_artifact_url(
+        "<build>", get_artifact_path(taskdesc, "mozharness.zip")
+    )
+
+    worker.setdefault("artifacts", [])
+    worker["artifacts"].extend(
+        [
+            {
+                "name": prefix,
+                "path": os.path.join("{workdir}/workspace".format(**run), path),
+                "type": "directory",
+                "expires-after": get_expiration(config, "default"),
+            }
+            for (prefix, path) in artifacts
+        ]
+    )
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "MOZHARNESS_CONFIG": " ".join(mozharness["config"]),
+            "MOZHARNESS_SCRIPT": mozharness["script"],
+            "MOZILLA_BUILD_URL": {"task-reference": installer},
+            "NEED_PULSEAUDIO": "true",
+            "NEED_WINDOW_MANAGER": "true",
+            "ENABLE_E10S": str(bool(test.get("e10s"))).lower(),
+            "WORKING_DIR": "/builds/worker",
+        }
+    )
+
+    env["PYTHON"] = "python3"
+
+    # Legacy linux64 tests rely on compiz.
+    if test.get("docker-image", {}).get("in-tree") == "desktop1604-test":
+        env.update({"NEED_COMPIZ": "true"})
+
+    # Bug 1602701/1601828 - use compiz on ubuntu1804 due to GTK asynchiness
+    # when manipulating windows.
+    if test.get("docker-image", {}).get("in-tree") == "ubuntu1804-test":
+        if "wdspec" in job["run"]["test"]["suite"] or (
+            "marionette" in job["run"]["test"]["suite"]
+            and "headless" not in job["label"]
+        ):
+            env.update({"NEED_COMPIZ": "true"})
+
+    # Set MOZ_ENABLE_WAYLAND env variables to enable Wayland backend.
+    if "wayland" in job["label"]:
+        env["MOZ_ENABLE_WAYLAND"] = "1"
+
+    if mozharness.get("mochitest-flavor"):
+        env["MOCHITEST_FLAVOR"] = mozharness["mochitest-flavor"]
+
+    if mozharness["set-moz-node-path"]:
+        env["MOZ_NODE_PATH"] = "/usr/local/bin/node"
+
+    if "actions" in mozharness:
+        env["MOZHARNESS_ACTIONS"] = " ".join(mozharness["actions"])
+
+    if is_try(config.params):
+        env["TRY_COMMIT_MSG"] = config.params["message"]
+
+    # handle some of the mozharness-specific options
+    if test["reboot"]:
+        raise Exception(
+            "reboot: {} not supported on generic-worker".format(test["reboot"])
+        )
+
+    # Support vcs checkouts regardless of whether the task runs from
+    # source or not in case it is needed on an interactive loaner.
+    support_vcs_checkout(config, job, taskdesc)
+
+    # If we have a source checkout, run mozharness from it instead of
+    # downloading a zip file with the same content.
+    if test["checkout"]:
+        env["MOZHARNESS_PATH"] = "{workdir}/checkouts/gecko/testing/mozharness".format(
+            **run
+        )
+    else:
+        env["MOZHARNESS_URL"] = {"task-reference": mozharness_url}
+
+    extra_config = {
+        "installer_url": installer,
+        "test_packages_url": test_packages_url(taskdesc),
+    }
+    env["EXTRA_MOZHARNESS_CONFIG"] = {
+        "task-reference": json.dumps(extra_config, sort_keys=True)
+    }
+
+    # Bug 1634554 - pass in decision task artifact URL to mozharness for WPT.
+    # Bug 1645974 - test-verify-wpt and test-coverage-wpt need artifact URL.
+    if "web-platform-tests" in test["suite"] or re.match(
+        "test-(coverage|verify)-wpt", test["suite"]
+    ):
+        env["TESTS_BY_MANIFEST_URL"] = {
+            "artifact-reference": "<decision/public/tests-by-manifest.json.gz>"
+        }
+
+    command = [
+        "{workdir}/bin/test-linux.sh".format(**run),
+    ]
+    command.extend(mozharness.get("extra-options", []))
+
+    if test.get("test-manifests"):
+        env["MOZHARNESS_TEST_PATHS"] = json.dumps(
+            {test["suite"]: test["test-manifests"]}, sort_keys=True
+        )
+
+    # TODO: remove the need for run['chunked']
+    elif mozharness.get("chunked") or test["chunks"] > 1:
+        command.append("--total-chunk={}".format(test["chunks"]))
+        command.append("--this-chunk={}".format(test["this-chunk"]))
+
+    if "download-symbols" in mozharness:
+        download_symbols = mozharness["download-symbols"]
+        download_symbols = {True: "true", False: "false"}.get(
+            download_symbols, download_symbols
+        )
+        command.append("--download-symbols=" + download_symbols)
+
+    job["run"] = {
+        "workdir": run["workdir"],
+        "tooltool-downloads": mozharness["tooltool-downloads"],
+        "checkout": test["checkout"],
+        "command": command,
+        "using": "run-task",
+    }
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
+
+
+@run_job_using("generic-worker", "mozharness-test", schema=mozharness_test_run_schema)
+def mozharness_test_on_generic_worker(config, job, taskdesc):
+    test = taskdesc["run"]["test"]
+    mozharness = test["mozharness"]
+    worker = taskdesc["worker"] = job["worker"]
+
+    bitbar_script = "test-linux.sh"
+
+    is_macosx = worker["os"] == "macosx"
+    is_windows = worker["os"] == "windows"
+    is_linux = worker["os"] == "linux" or worker["os"] == "linux-bitbar"
+    is_bitbar = worker["os"] == "linux-bitbar"
+    assert is_macosx or is_windows or is_linux
+
+    artifacts = [
+        {
+            "name": "public/logs",
+            "path": "logs",
+            "type": "directory",
+            "expires-after": get_expiration(config, "default"),
+        }
+    ]
+
+    # jittest doesn't have blob_upload_dir
+    if test["test-name"] != "jittest":
+        artifacts.append(
+            {
+                "name": "public/test_info",
+                "path": "build/blobber_upload_dir",
+                "type": "directory",
+                "expires-after": get_expiration(config, "default"),
+            }
+        )
+
+    if is_bitbar:
+        artifacts = [
+            {
+                "name": "public/test/",
+                "path": "artifacts/public",
+                "type": "directory",
+                "expires-after": get_expiration(config, "default"),
+            },
+            {
+                "name": "public/logs/",
+                "path": "workspace/logs",
+                "type": "directory",
+                "expires-after": get_expiration(config, "default"),
+            },
+            {
+                "name": "public/test_info/",
+                "path": "workspace/build/blobber_upload_dir",
+                "type": "directory",
+                "expires-after": get_expiration(config, "default"),
+            },
+        ]
+
+    installer = installer_url(taskdesc)
+
+    worker["os-groups"] = test["os-groups"]
+
+    # run-as-administrator is a feature for workers with UAC enabled and as such should not be
+    # included in tasks on workers that have UAC disabled. Currently UAC is only enabled on
+    # gecko Windows 10 workers, however this may be subject to change. Worker type
+    # environment definitions can be found in https://github.com/mozilla-releng/OpenCloudConfig
+    # See https://docs.microsoft.com/en-us/windows/desktop/secauthz/user-account-control
+    # for more information about UAC.
+    if test.get("run-as-administrator", False):
+        if job["worker-type"].startswith("win10-64") or job["worker-type"].startswith(
+            "win11-64"
+        ):
+            worker["run-as-administrator"] = True
+        else:
+            raise Exception(
+                "run-as-administrator not supported on {}".format(job["worker-type"])
+            )
+
+    if test["reboot"]:
+        raise Exception(
+            "reboot: {} not supported on generic-worker".format(test["reboot"])
+        )
+
+    worker["max-run-time"] = test["max-run-time"]
+    worker["retry-exit-status"] = test["retry-exit-status"]
+    worker.setdefault("artifacts", [])
+    worker["artifacts"].extend(artifacts)
+
+    env = worker.setdefault("env", {})
+    env["GECKO_HEAD_REPOSITORY"] = config.params["head_repository"]
+    env["GECKO_HEAD_REV"] = config.params["head_rev"]
+
+    # this list will get cleaned up / reduced / removed in bug 1354088
+    if is_macosx:
+        env.update(
+            {
+                "LC_ALL": "en_US.UTF-8",
+                "LANG": "en_US.UTF-8",
+                "MOZ_NODE_PATH": "/usr/local/bin/node",
+                "PATH": "/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin",
+                "SHELL": "/bin/bash",
+            }
+        )
+    elif is_bitbar:
+        env.update(
+            {
+                "LANG": "en_US.UTF-8",
+                "MOZHARNESS_CONFIG": " ".join(mozharness["config"]),
+                "MOZHARNESS_SCRIPT": mozharness["script"],
+                "MOZHARNESS_URL": {
+                    "artifact-reference": "<build/public/build/mozharness.zip>"
+                },
+                "MOZILLA_BUILD_URL": {"task-reference": installer},
+                "MOZ_NO_REMOTE": "1",
+                "NEED_XVFB": "false",
+                "XPCOM_DEBUG_BREAK": "warn",
+                "NO_FAIL_ON_TEST_ERRORS": "1",
+                "MOZ_HIDE_RESULTS_TABLE": "1",
+                "MOZ_NODE_PATH": "/usr/local/bin/node",
+                "TASKCLUSTER_WORKER_TYPE": job["worker-type"],
+            }
+        )
+
+    extra_config = {
+        "installer_url": installer,
+        "test_packages_url": test_packages_url(taskdesc),
+    }
+    env["EXTRA_MOZHARNESS_CONFIG"] = {
+        "task-reference": json.dumps(extra_config, sort_keys=True)
+    }
+
+    # Bug 1634554 - pass in decision task artifact URL to mozharness for WPT.
+    # Bug 1645974 - test-verify-wpt and test-coverage-wpt need artifact URL.
+    if "web-platform-tests" in test["suite"] or re.match(
+        "test-(coverage|verify)-wpt", test["suite"]
+    ):
+        env["TESTS_BY_MANIFEST_URL"] = {
+            "artifact-reference": "<decision/public/tests-by-manifest.json.gz>"
+        }
+
+    if is_windows:
+        py_binary = "c:\\mozilla-build\\{python}\\{python}.exe".format(python="python3")
+        mh_command = [
+            py_binary,
+            "-u",
+            "mozharness\\scripts\\" + normpath(mozharness["script"]),
+        ]
+    elif is_bitbar:
+        py_binary = "python3"
+        mh_command = ["bash", f"./{bitbar_script}"]
+    elif is_macosx:
+        py_binary = "/usr/local/bin/{}".format("python3")
+        mh_command = [
+            py_binary,
+            "-u",
+            "mozharness/scripts/" + mozharness["script"],
+        ]
+    else:
+        # is_linux
+        py_binary = "/usr/bin/{}".format("python3")
+        mh_command = [
+            # Using /usr/bin/python2.7 rather than python2.7 because
+            # /usr/local/bin/python2.7 is broken on the mac workers.
+            # See bug #1547903.
+            py_binary,
+            "-u",
+            "mozharness/scripts/" + mozharness["script"],
+        ]
+
+    env["PYTHON"] = py_binary
+
+    for mh_config in mozharness["config"]:
+        cfg_path = "mozharness/configs/" + mh_config
+        if is_windows:
+            cfg_path = normpath(cfg_path)
+        mh_command.extend(["--cfg", cfg_path])
+    mh_command.extend(mozharness.get("extra-options", []))
+    if mozharness.get("download-symbols"):
+        if isinstance(mozharness["download-symbols"], str):
+            mh_command.extend(["--download-symbols", mozharness["download-symbols"]])
+        else:
+            mh_command.extend(["--download-symbols", "true"])
+    if mozharness.get("include-blob-upload-branch"):
+        mh_command.append("--blob-upload-branch=" + config.params["project"])
+
+    if test.get("test-manifests"):
+        env["MOZHARNESS_TEST_PATHS"] = json.dumps(
+            {test["suite"]: test["test-manifests"]}, sort_keys=True
+        )
+
+    # TODO: remove the need for run['chunked']
+    elif mozharness.get("chunked") or test["chunks"] > 1:
+        mh_command.append("--total-chunk={}".format(test["chunks"]))
+        mh_command.append("--this-chunk={}".format(test["this-chunk"]))
+
+    if is_try(config.params):
+        env["TRY_COMMIT_MSG"] = config.params["message"]
+
+    worker["mounts"] = [
+        {
+            "directory": "mozharness",
+            "content": {
+                "artifact": get_artifact_path(taskdesc, "mozharness.zip"),
+                "task-id": {"task-reference": "<build>"},
+            },
+            "format": "zip",
+        }
+    ]
+    if is_bitbar:
+        a_url = config.params.file_url(
+            f"taskcluster/scripts/tester/{bitbar_script}",
+        )
+        worker["mounts"] = [
+            {
+                "file": bitbar_script,
+                "content": {
+                    "url": a_url,
+                },
+            }
+        ]
+
+    job["run"] = {
+        "tooltool-downloads": mozharness["tooltool-downloads"],
+        "checkout": test["checkout"],
+        "command": mh_command,
+        "using": "run-task",
+    }
+    if is_bitbar:
+        job["run"]["run-as-root"] = True
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
diff --git a/taskcluster/gecko_taskgraph/transforms/job/python_test.py b/taskcluster/gecko_taskgraph/transforms/job/python_test.py
new file mode 100644
index 0000000000..b572061217
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/python_test.py
@@ -0,0 +1,47 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running mach python-test tasks (via run-task)
+"""
+
+
+from taskgraph.util.schema import Schema
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+
+python_test_schema = Schema(
+    {
+        Required("using"): "python-test",
+        # Python version to use
+        Required("python-version"): int,
+        # The subsuite to run
+        Required("subsuite"): str,
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+    }
+)
+
+
+defaults = {
+    "python-version": 3,
+    "subsuite": "default",
+}
+
+
+@run_job_using(
+    "docker-worker", "python-test", schema=python_test_schema, defaults=defaults
+)
+@run_job_using(
+    "generic-worker", "python-test", schema=python_test_schema, defaults=defaults
+)
+def configure_python_test(config, job, taskdesc):
+    run = job["run"]
+    worker = job["worker"]
+
+    # defer to the mach implementation
+    run["mach"] = ("python-test --subsuite {subsuite} --run-slow").format(**run)
+    run["using"] = "mach"
+    del run["subsuite"]
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
diff --git a/taskcluster/gecko_taskgraph/transforms/job/run_task.py b/taskcluster/gecko_taskgraph/transforms/job/run_task.py
new file mode 100644
index 0000000000..201c0b825a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/run_task.py
@@ -0,0 +1,308 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running jobs that are invoked via the `run-task` script.
+"""
+
+
+import os
+
+from mozbuild.util import memoize
+from mozpack import path
+from taskgraph.util.schema import Schema
+from taskgraph.util.yaml import load_yaml
+from voluptuous import Any, Extra, Optional, Required
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.transforms.job import run_job_using
+from gecko_taskgraph.transforms.job.common import add_tooltool, support_vcs_checkout
+from gecko_taskgraph.transforms.task import taskref_or_string
+
+run_task_schema = Schema(
+    {
+        Required("using"): "run-task",
+        # if true, add a cache at ~worker/.cache, which is where things like pip
+        # tend to hide their caches.  This cache is never added for level-1 jobs.
+        # TODO Once bug 1526028 is fixed, this and 'use-caches' should be merged.
+        Required("cache-dotcache"): bool,
+        # Whether or not to use caches.
+        Optional("use-caches"): bool,
+        # if true (the default), perform a checkout of gecko on the worker
+        Required("checkout"): bool,
+        Optional(
+            "cwd",
+            description="Path to run command in. If a checkout is present, the path "
+            "to the checkout will be interpolated with the key `checkout`",
+        ): str,
+        # The sparse checkout profile to use. Value is the filename relative to
+        # "sparse-profile-prefix" which defaults to "build/sparse-profiles/".
+        Required("sparse-profile"): Any(str, None),
+        # The relative path to the sparse profile.
+        Optional("sparse-profile-prefix"): str,
+        # if true, perform a checkout of a comm-central based branch inside the
+        # gecko checkout
+        Required("comm-checkout"): bool,
+        # The command arguments to pass to the `run-task` script, after the
+        # checkout arguments.  If a list, it will be passed directly; otherwise
+        # it will be included in a single argument to `bash -cx`.
+        Required("command"): Any([taskref_or_string], taskref_or_string),
+        # Context to substitute into the command using format string
+        # substitution (e.g {value}). This is useful if certain aspects of the
+        # command need to be generated in transforms.
+        Optional("command-context"): {
+            # If present, loads a set of context variables from an unnested yaml
+            # file. If a value is present in both the provided file and directly
+            # in command-context, the latter will take priority.
+            Optional("from-file"): str,
+            Extra: object,
+        },
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+        # If not false, tooltool downloads will be enabled via relengAPIProxy
+        # for either just public files, or all files. Only supported on
+        # docker-worker.
+        Required("tooltool-downloads"): Any(
+            False,
+            "public",
+            "internal",
+        ),
+        # Whether to run as root. (defaults to False)
+        Optional("run-as-root"): bool,
+    }
+)
+
+
+def common_setup(config, job, taskdesc, command):
+    run = job["run"]
+    if run["checkout"]:
+        support_vcs_checkout(config, job, taskdesc, sparse=bool(run["sparse-profile"]))
+        command.append(
+            "--gecko-checkout={}".format(taskdesc["worker"]["env"]["GECKO_PATH"])
+        )
+
+    if run["sparse-profile"]:
+        sparse_profile_prefix = run.pop(
+            "sparse-profile-prefix", "build/sparse-profiles"
+        )
+        sparse_profile_path = path.join(sparse_profile_prefix, run["sparse-profile"])
+        command.append(f"--gecko-sparse-profile={sparse_profile_path}")
+
+    taskdesc["worker"].setdefault("env", {})["MOZ_SCM_LEVEL"] = config.params["level"]
+
+
+worker_defaults = {
+    "cache-dotcache": False,
+    "checkout": True,
+    "comm-checkout": False,
+    "sparse-profile": None,
+    "tooltool-downloads": False,
+    "run-as-root": False,
+}
+
+
+load_yaml = memoize(load_yaml)
+
+
+def script_url(config, script):
+    if "MOZ_AUTOMATION" in os.environ and "TASK_ID" not in os.environ:
+        raise Exception("TASK_ID must be defined to use run-task on generic-worker")
+    task_id = os.environ.get("TASK_ID", "<TASK_ID>")
+    tc_url = "http://firefox-ci-tc.services.mozilla.com"
+    return f"{tc_url}/api/queue/v1/task/{task_id}/artifacts/public/{script}"
+
+
+def substitute_command_context(command_context, command):
+    from_file = command_context.pop("from-file", None)
+    full_context = {}
+    if from_file:
+        full_context = load_yaml(os.path.join(GECKO, from_file))
+    else:
+        full_context = {}
+
+    full_context.update(command_context)
+
+    if isinstance(command, list):
+        for i in range(len(command)):
+            command[i] = command[i].format(**full_context)
+    else:
+        command = command.format(**full_context)
+
+    return command
+
+
+@run_job_using(
+    "docker-worker", "run-task", schema=run_task_schema, defaults=worker_defaults
+)
+def docker_worker_run_task(config, job, taskdesc):
+    run = job["run"]
+    worker = taskdesc["worker"] = job["worker"]
+    command = ["/builds/worker/bin/run-task"]
+    common_setup(config, job, taskdesc, command)
+
+    if run["tooltool-downloads"]:
+        internal = run["tooltool-downloads"] == "internal"
+        add_tooltool(config, job, taskdesc, internal=internal)
+
+    if run.get("cache-dotcache"):
+        worker["caches"].append(
+            {
+                "type": "persistent",
+                "name": "{project}-dotcache".format(**config.params),
+                "mount-point": "{workdir}/.cache".format(**run),
+                "skip-untrusted": True,
+            }
+        )
+
+    if run.get("command-context"):
+        run_command = substitute_command_context(
+            run.get("command-context"), run["command"]
+        )
+    else:
+        run_command = run["command"]
+
+    run_cwd = run.get("cwd")
+    if run_cwd and run["checkout"]:
+        run_cwd = path.normpath(
+            run_cwd.format(checkout=taskdesc["worker"]["env"]["GECKO_PATH"])
+        )
+    elif run_cwd and "{checkout}" in run_cwd:
+        raise Exception(
+            "Found `{{checkout}}` interpolation in `cwd` for task {name} "
+            "but the task doesn't have a checkout: {cwd}".format(
+                cwd=run_cwd, name=job.get("name", job.get("label"))
+            )
+        )
+
+    # dict is for the case of `{'task-reference': text_type}`.
+    if isinstance(run_command, (str, dict)):
+        run_command = ["bash", "-cx", run_command]
+    if run["comm-checkout"]:
+        command.append(
+            "--comm-checkout={}/comm".format(taskdesc["worker"]["env"]["GECKO_PATH"])
+        )
+    if run["run-as-root"]:
+        command.extend(("--user", "root", "--group", "root"))
+    if run_cwd:
+        command.extend(("--task-cwd", run_cwd))
+    command.append("--")
+    command.extend(run_command)
+    worker["command"] = command
+
+
+@run_job_using(
+    "generic-worker", "run-task", schema=run_task_schema, defaults=worker_defaults
+)
+def generic_worker_run_task(config, job, taskdesc):
+    run = job["run"]
+    worker = taskdesc["worker"] = job["worker"]
+    is_win = worker["os"] == "windows"
+    is_mac = worker["os"] == "macosx"
+    is_bitbar = worker["os"] == "linux-bitbar"
+
+    if run["tooltool-downloads"]:
+        internal = run["tooltool-downloads"] == "internal"
+        add_tooltool(config, job, taskdesc, internal=internal)
+
+    if is_win:
+        command = ["C:/mozilla-build/python3/python3.exe", "run-task"]
+    elif is_mac:
+        command = ["/usr/local/bin/python3", "run-task"]
+    else:
+        command = ["./run-task"]
+
+    common_setup(config, job, taskdesc, command)
+
+    worker.setdefault("mounts", [])
+    if run.get("cache-dotcache"):
+        worker["mounts"].append(
+            {
+                "cache-name": "{project}-dotcache".format(**config.params),
+                "directory": "{workdir}/.cache".format(**run),
+            }
+        )
+    worker["mounts"].append(
+        {
+            "content": {
+                "url": script_url(config, "run-task"),
+            },
+            "file": "./run-task",
+        }
+    )
+    if job.get("fetches", {}):
+        worker["mounts"].append(
+            {
+                "content": {
+                    "url": script_url(config, "fetch-content"),
+                },
+                "file": "./fetch-content",
+            }
+        )
+
+    run_command = run["command"]
+    run_cwd = run.get("cwd")
+    if run_cwd and run["checkout"]:
+        run_cwd = path.normpath(
+            run_cwd.format(checkout=taskdesc["worker"]["env"]["GECKO_PATH"])
+        )
+    elif run_cwd and "{checkout}" in run_cwd:
+        raise Exception(
+            "Found `{{checkout}}` interpolation in `cwd` for task {name} "
+            "but the task doesn't have a checkout: {cwd}".format(
+                cwd=run_cwd, name=job.get("name", job.get("label"))
+            )
+        )
+
+    # dict is for the case of `{'task-reference': text_type}`.
+    if isinstance(run_command, (str, dict)):
+        if is_win:
+            if isinstance(run_command, dict):
+                for k in run_command.keys():
+                    run_command[k] = f'"{run_command[k]}"'
+            else:
+                run_command = f'"{run_command}"'
+        run_command = ["bash", "-cx", run_command]
+
+    if run.get("command-context"):
+        run_command = substitute_command_context(
+            run.get("command-context"), run_command
+        )
+
+    if run["comm-checkout"]:
+        command.append(
+            "--comm-checkout={}/comm".format(taskdesc["worker"]["env"]["GECKO_PATH"])
+        )
+
+    if run["run-as-root"]:
+        command.extend(("--user", "root", "--group", "root"))
+    if run_cwd:
+        command.extend(("--task-cwd", run_cwd))
+    command.append("--")
+    if is_bitbar:
+        # Use the bitbar wrapper script which sets up the device and adb
+        # environment variables
+        command.append("/builds/taskcluster/script.py")
+    command.extend(run_command)
+
+    if is_win:
+        taskref = False
+        for c in command:
+            if isinstance(c, dict):
+                taskref = True
+
+        if taskref:
+            cmd = []
+            for c in command:
+                if isinstance(c, dict):
+                    for v in c.values():
+                        cmd.append(v)
+                else:
+                    cmd.append(c)
+            worker["command"] = [{"artifact-reference": " ".join(cmd)}]
+        else:
+            worker["command"] = [" ".join(command)]
+    else:
+        worker["command"] = [
+            ["chmod", "+x", "run-task"],
+            command,
+        ]
diff --git a/taskcluster/gecko_taskgraph/transforms/job/spidermonkey.py b/taskcluster/gecko_taskgraph/transforms/job/spidermonkey.py
new file mode 100644
index 0000000000..91c7e93bd6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/spidermonkey.py
@@ -0,0 +1,109 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running spidermonkey jobs via dedicated scripts
+"""
+
+
+from taskgraph.util.schema import Schema
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+from gecko_taskgraph.transforms.job.common import (
+    docker_worker_add_artifacts,
+    generic_worker_add_artifacts,
+)
+
+sm_run_schema = Schema(
+    {
+        Required("using"): Any(
+            "spidermonkey",
+            "spidermonkey-package",
+        ),
+        # SPIDERMONKEY_VARIANT and SPIDERMONKEY_PLATFORM
+        Required("spidermonkey-variant"): str,
+        Optional("spidermonkey-platform"): str,
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+        Required("tooltool-downloads"): Any(
+            False,
+            "public",
+            "internal",
+        ),
+    }
+)
+
+
+@run_job_using("docker-worker", "spidermonkey", schema=sm_run_schema)
+@run_job_using("docker-worker", "spidermonkey-package", schema=sm_run_schema)
+def docker_worker_spidermonkey(config, job, taskdesc):
+    run = job["run"]
+
+    worker = taskdesc["worker"] = job["worker"]
+    worker.setdefault("artifacts", [])
+
+    docker_worker_add_artifacts(config, job, taskdesc)
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "MOZHARNESS_DISABLE": "true",
+            "SPIDERMONKEY_VARIANT": run.pop("spidermonkey-variant"),
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+        }
+    )
+    if "spidermonkey-platform" in run:
+        env["SPIDERMONKEY_PLATFORM"] = run.pop("spidermonkey-platform")
+
+    script = "build-sm.sh"
+    if run["using"] == "spidermonkey-package":
+        script = "build-sm-package.sh"
+
+    run["using"] = "run-task"
+    run["cwd"] = run["workdir"]
+    run["command"] = [f"./checkouts/gecko/taskcluster/scripts/builder/{script}"]
+
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
+
+
+@run_job_using("generic-worker", "spidermonkey", schema=sm_run_schema)
+def generic_worker_spidermonkey(config, job, taskdesc):
+    assert job["worker"]["os"] == "windows", "only supports windows right now"
+
+    run = job["run"]
+
+    worker = taskdesc["worker"] = job["worker"]
+
+    generic_worker_add_artifacts(config, job, taskdesc)
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "MOZHARNESS_DISABLE": "true",
+            "SPIDERMONKEY_VARIANT": run.pop("spidermonkey-variant"),
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+            "SCCACHE_DISABLE": "1",
+            "WORK": ".",  # Override the defaults in build scripts
+            "GECKO_PATH": "./src",  # with values suiteable for windows generic worker
+            "UPLOAD_DIR": "./public/build",
+        }
+    )
+    if "spidermonkey-platform" in run:
+        env["SPIDERMONKEY_PLATFORM"] = run.pop("spidermonkey-platform")
+
+    script = "build-sm.sh"
+    if run["using"] == "spidermonkey-package":
+        script = "build-sm-package.sh"
+        # Don't allow untested configurations yet
+        raise Exception("spidermonkey-package is not a supported configuration")
+
+    run["using"] = "run-task"
+    run["command"] = [
+        "c:\\mozilla-build\\msys2\\usr\\bin\\bash.exe "  # string concat
+        '"./src/taskcluster/scripts/builder/%s"' % script
+    ]
+
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
diff --git a/taskcluster/gecko_taskgraph/transforms/job/toolchain.py b/taskcluster/gecko_taskgraph/transforms/job/toolchain.py
new file mode 100644
index 0000000000..fb030019fc
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/job/toolchain.py
@@ -0,0 +1,257 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Support for running toolchain-building jobs via dedicated scripts
+"""
+
+
+import os
+
+import taskgraph
+from mozbuild.shellutil import quote as shell_quote
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
+from gecko_taskgraph.transforms.job.common import (
+    docker_worker_add_artifacts,
+    generic_worker_add_artifacts,
+)
+from gecko_taskgraph.util.attributes import RELEASE_PROJECTS
+from gecko_taskgraph.util.hash import hash_paths
+
+CACHE_TYPE = "toolchains.v3"
+
+toolchain_run_schema = Schema(
+    {
+        Required("using"): "toolchain-script",
+        # The script (in taskcluster/scripts/misc) to run.
+        # Python scripts are invoked with `mach python` so vendored libraries
+        # are available.
+        Required("script"): str,
+        # Arguments to pass to the script.
+        Optional("arguments"): [str],
+        # If not false, tooltool downloads will be enabled via relengAPIProxy
+        # for either just public files, or all files.  Not supported on Windows
+        Required("tooltool-downloads"): Any(
+            False,
+            "public",
+            "internal",
+        ),
+        # Sparse profile to give to checkout using `run-task`.  If given,
+        # Defaults to "toolchain-build". The value is relative to
+        # "sparse-profile-prefix", optionally defined below is the path,
+        # defaulting to "build/sparse-profiles".
+        # i.e. `build/sparse-profiles/toolchain-build`.
+        # If `None`, instructs `run-task` to not use a sparse profile at all.
+        Required("sparse-profile"): Any(str, None),
+        # The relative path to the sparse profile.
+        Optional("sparse-profile-prefix"): str,
+        # Paths/patterns pointing to files that influence the outcome of a
+        # toolchain build.
+        Optional("resources"): [str],
+        # Path to the artifact produced by the toolchain job
+        Required("toolchain-artifact"): str,
+        Optional(
+            "toolchain-alias",
+            description="An alias that can be used instead of the real toolchain job name in "
+            "fetch stanzas for jobs.",
+        ): optionally_keyed_by("project", Any(None, str, [str])),
+        Optional(
+            "toolchain-env",
+            description="Additional env variables to add to the worker when using this toolchain",
+        ): {str: object},
+        # Base work directory used to set up the task.
+        Optional("workdir"): str,
+    }
+)
+
+
+def get_digest_data(config, run, taskdesc):
+    files = list(run.pop("resources", []))
+    # The script
+    files.append("taskcluster/scripts/misc/{}".format(run["script"]))
+    # Tooltool manifest if any is defined:
+    tooltool_manifest = taskdesc["worker"]["env"].get("TOOLTOOL_MANIFEST")
+    if tooltool_manifest:
+        files.append(tooltool_manifest)
+
+    # Accumulate dependency hashes for index generation.
+    data = [hash_paths(GECKO, files)]
+
+    data.append(taskdesc["attributes"]["toolchain-artifact"])
+
+    # If the task uses an in-tree docker image, we want it to influence
+    # the index path as well. Ideally, the content of the docker image itself
+    # should have an influence, but at the moment, we can't get that
+    # information here. So use the docker image name as a proxy. Not a lot of
+    # changes to docker images actually have an impact on the resulting
+    # toolchain artifact, so we'll just rely on such important changes to be
+    # accompanied with a docker image name change.
+    image = taskdesc["worker"].get("docker-image", {}).get("in-tree")
+    if image:
+        data.append(image)
+
+    # Likewise script arguments should influence the index.
+    args = run.get("arguments")
+    if args:
+        data.extend(args)
+
+    if taskdesc["attributes"].get("rebuild-on-release"):
+        # Add whether this is a release branch or not
+        data.append(str(config.params["project"] in RELEASE_PROJECTS))
+    return data
+
+
+def common_toolchain(config, job, taskdesc, is_docker):
+    run = job["run"]
+
+    worker = taskdesc["worker"] = job["worker"]
+    worker["chain-of-trust"] = True
+
+    if is_docker:
+        # If the task doesn't have a docker-image, set a default
+        worker.setdefault("docker-image", {"in-tree": "deb11-toolchain-build"})
+
+    if job["worker"]["os"] == "windows":
+        # There were no caches on generic-worker before bug 1519472, and they cause
+        # all sorts of problems with Windows toolchain tasks, disable them until
+        # tasks are ready.
+        run["use-caches"] = False
+
+    env = worker.setdefault("env", {})
+    env.update(
+        {
+            "MOZ_BUILD_DATE": config.params["moz_build_date"],
+            "MOZ_SCM_LEVEL": config.params["level"],
+            "TOOLCHAIN_ARTIFACT": run["toolchain-artifact"],
+        }
+    )
+
+    if is_docker:
+        # Toolchain checkouts don't live under {workdir}/checkouts
+        workspace = "{workdir}/workspace/build".format(**run)
+        env["GECKO_PATH"] = f"{workspace}/src"
+
+    attributes = taskdesc.setdefault("attributes", {})
+    attributes["toolchain-artifact"] = run.pop("toolchain-artifact")
+    toolchain_artifact = attributes["toolchain-artifact"]
+    if not toolchain_artifact.startswith("public/build/"):
+        if "artifact_prefix" in attributes:
+            raise Exception(
+                "Toolchain {} has an artifact_prefix attribute. That is not"
+                " allowed on toolchain tasks.".format(taskdesc["label"])
+            )
+        attributes["artifact_prefix"] = os.path.dirname(toolchain_artifact)
+
+    resolve_keyed_by(
+        run,
+        "toolchain-alias",
+        item_name=taskdesc["label"],
+        project=config.params["project"],
+    )
+    alias = run.pop("toolchain-alias", None)
+    if alias:
+        attributes["toolchain-alias"] = alias
+    if "toolchain-env" in run:
+        attributes["toolchain-env"] = run.pop("toolchain-env")
+
+    # Allow the job to specify where artifacts come from, but add
+    # public/build if it's not there already.
+    artifacts = worker.setdefault("artifacts", [])
+    if not artifacts:
+        if is_docker:
+            docker_worker_add_artifacts(config, job, taskdesc)
+        else:
+            generic_worker_add_artifacts(config, job, taskdesc)
+
+    digest_data = get_digest_data(config, run, taskdesc)
+
+    if job.get("attributes", {}).get("cached_task") is not False and not taskgraph.fast:
+        name = taskdesc["label"].replace(f"{config.kind}-", "", 1)
+        taskdesc["cache"] = {
+            "type": CACHE_TYPE,
+            "name": name,
+            "digest-data": digest_data,
+        }
+
+    # Toolchains that are used for local development need to be built on a
+    # level-3 branch to be installable via `mach bootstrap`.
+    local_toolchain = taskdesc["attributes"].get("local-toolchain")
+    if local_toolchain:
+        if taskdesc.get("run-on-projects"):
+            raise Exception(
+                "Toolchain {} used for local developement must not have"
+                " run-on-projects set".format(taskdesc["label"])
+            )
+        taskdesc["run-on-projects"] = ["integration", "release"]
+
+    script = run.pop("script")
+    arguments = run.pop("arguments", [])
+    if local_toolchain and not attributes["toolchain-artifact"].startswith("public/"):
+        # Local toolchains with private artifacts are expected to have a script that
+        # fill a directory given as a final command line argument. That script, and the
+        # arguments provided, are used by the build system bootstrap code, and for the
+        # corresponding CI tasks, the command is wrapped with a script that creates an
+        # artifact based on that filled directory.
+        # We prefer automatic wrapping rather than manual wrapping in the yaml because
+        # it makes the index independent of the wrapper script, which is irrelevant.
+        # Also, an attribute is added for the bootstrap code to be able to easily parse
+        # the command.
+        attributes["toolchain-command"] = {
+            "script": script,
+            "arguments": list(arguments),
+        }
+        arguments.insert(0, script)
+        script = "private_local_toolchain.sh"
+
+    run["using"] = "run-task"
+    if is_docker:
+        gecko_path = "workspace/build/src"
+    elif job["worker"]["os"] == "windows":
+        gecko_path = "%GECKO_PATH%"
+    else:
+        gecko_path = "$GECKO_PATH"
+
+    if is_docker:
+        run["cwd"] = run["workdir"]
+    run["command"] = [
+        "{}/taskcluster/scripts/misc/{}".format(gecko_path, script)
+    ] + arguments
+    if not is_docker:
+        # Don't quote the first item in the command because it purposely contains
+        # an environment variable that is not meant to be quoted.
+        if len(run["command"]) > 1:
+            run["command"] = run["command"][0] + " " + shell_quote(*run["command"][1:])
+        else:
+            run["command"] = run["command"][0]
+
+    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])
+
+
+toolchain_defaults = {
+    "tooltool-downloads": False,
+    "sparse-profile": "toolchain-build",
+}
+
+
+@run_job_using(
+    "docker-worker",
+    "toolchain-script",
+    schema=toolchain_run_schema,
+    defaults=toolchain_defaults,
+)
+def docker_worker_toolchain(config, job, taskdesc):
+    common_toolchain(config, job, taskdesc, is_docker=True)
+
+
+@run_job_using(
+    "generic-worker",
+    "toolchain-script",
+    schema=toolchain_run_schema,
+    defaults=toolchain_defaults,
+)
+def generic_worker_toolchain(config, job, taskdesc):
+    common_toolchain(config, job, taskdesc, is_docker=False)
diff --git a/taskcluster/gecko_taskgraph/transforms/l10n.py b/taskcluster/gecko_taskgraph/transforms/l10n.py
new file mode 100644
index 0000000000..e36c70246b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/l10n.py
@@ -0,0 +1,416 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Do transforms specific to l10n kind
+"""
+
+
+import json
+
+from mozbuild.chunkify import chunkify
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import (
+    optionally_keyed_by,
+    resolve_keyed_by,
+    taskref_or_string,
+)
+from taskgraph.util.taskcluster import get_artifact_prefix
+from taskgraph.util.treeherder import add_suffix
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.loader.multi_dep import schema
+from gecko_taskgraph.transforms.job import job_description_schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    task_name,
+)
+from gecko_taskgraph.util.copy_task import copy_task
+
+
+def _by_platform(arg):
+    return optionally_keyed_by("build-platform", arg)
+
+
+l10n_description_schema = schema.extend(
+    {
+        # Name for this job, inferred from the dependent job before validation
+        Required("name"): str,
+        # build-platform, inferred from dependent job before validation
+        Required("build-platform"): str,
+        # max run time of the task
+        Required("run-time"): _by_platform(int),
+        # Locales not to repack for
+        Required("ignore-locales"): _by_platform([str]),
+        # All l10n jobs use mozharness
+        Required("mozharness"): {
+            # Script to invoke for mozharness
+            Required("script"): _by_platform(str),
+            # Config files passed to the mozharness script
+            Required("config"): _by_platform([str]),
+            # Additional paths to look for mozharness configs in. These should be
+            # relative to the base of the source checkout
+            Optional("config-paths"): [str],
+            # Options to pass to the mozharness script
+            Optional("options"): _by_platform([str]),
+            # Action commands to provide to mozharness script
+            Required("actions"): _by_platform([str]),
+            # if true, perform a checkout of a comm-central based branch inside the
+            # gecko checkout
+            Optional("comm-checkout"): bool,
+        },
+        # Items for the taskcluster index
+        Optional("index"): {
+            # Product to identify as in the taskcluster index
+            Required("product"): _by_platform(str),
+            # Job name to identify as in the taskcluster index
+            Required("job-name"): _by_platform(str),
+            # Type of index
+            Optional("type"): _by_platform(str),
+        },
+        # Description of the localized task
+        Required("description"): _by_platform(str),
+        Optional("run-on-projects"): job_description_schema["run-on-projects"],
+        # worker-type to utilize
+        Required("worker-type"): _by_platform(str),
+        # File which contains the used locales
+        Required("locales-file"): _by_platform(str),
+        # Tooltool visibility required for task.
+        Required("tooltool"): _by_platform(Any("internal", "public")),
+        # Docker image required for task.  We accept only in-tree images
+        # -- generally desktop-build or android-build -- for now.
+        Optional("docker-image"): _by_platform(
+            # an in-tree generated docker image (from `taskcluster/docker/<name>`)
+            {"in-tree": str},
+        ),
+        Optional("fetches"): {
+            str: _by_platform([str]),
+        },
+        # The set of secret names to which the task has access; these are prefixed
+        # with `project/releng/gecko/{treeherder.kind}/level-{level}/`.  Setting
+        # this will enable any worker features required and set the task's scopes
+        # appropriately.  `true` here means ['*'], all secrets.  Not supported on
+        # Windows
+        Optional("secrets"): _by_platform(Any(bool, [str])),
+        # Information for treeherder
+        Required("treeherder"): {
+            # Platform to display the task on in treeherder
+            Required("platform"): _by_platform(str),
+            # Symbol to use
+            Required("symbol"): str,
+            # Tier this task is
+            Required("tier"): _by_platform(int),
+        },
+        # Extra environment values to pass to the worker
+        Optional("env"): _by_platform({str: taskref_or_string}),
+        # Max number locales per chunk
+        Optional("locales-per-chunk"): _by_platform(int),
+        # Task deps to chain this task with, added in transforms from primary-dependency
+        # if this is a shippable-style build
+        Optional("dependencies"): {str: str},
+        # Run the task when the listed files change (if present).
+        Optional("when"): {"files-changed": [str]},
+        # passed through directly to the job description
+        Optional("attributes"): job_description_schema["attributes"],
+        Optional("extra"): job_description_schema["extra"],
+        # Shipping product and phase
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+transforms = TransformSequence()
+
+
+def parse_locales_file(locales_file, platform=None):
+    """Parse the passed locales file for a list of locales."""
+    locales = []
+
+    with open(locales_file, mode="r") as f:
+        if locales_file.endswith("json"):
+            all_locales = json.load(f)
+            # XXX Only single locales are fetched
+            locales = {
+                locale: data["revision"]
+                for locale, data in all_locales.items()
+                if platform is None or platform in data["platforms"]
+            }
+        else:
+            all_locales = f.read().split()
+            # 'default' is the hg revision at the top of hg repo, in this context
+            locales = {locale: "default" for locale in all_locales}
+    return locales
+
+
+def _remove_locales(locales, to_remove=None):
+    # ja-JP-mac is a mac-only locale, but there are no mac builds being repacked,
+    # so just omit it unconditionally
+    return {
+        locale: revision
+        for locale, revision in locales.items()
+        if locale not in to_remove
+    }
+
+
+@transforms.add
+def setup_name(config, jobs):
+    for job in jobs:
+        dep = job["primary-dependency"]
+        # Set the name to the same as the dep task, without kind name.
+        # Label will get set automatically with this kinds name.
+        job["name"] = job.get("name", task_name(dep))
+        yield job
+
+
+@transforms.add
+def copy_in_useful_magic(config, jobs):
+    for job in jobs:
+        dep = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep)
+        attributes.update(job.get("attributes", {}))
+        # build-platform is needed on `job` for by-build-platform
+        job["build-platform"] = attributes.get("build_platform")
+        job["attributes"] = attributes
+        yield job
+
+
+transforms.add_validate(l10n_description_schema)
+
+
+@transforms.add
+def setup_shippable_dependency(config, jobs):
+    """Sets up a task dependency to the signing job this relates to"""
+    for job in jobs:
+        job["dependencies"] = {"build": job["dependent-tasks"]["build"].label}
+        if job["attributes"]["build_platform"].startswith("win") or job["attributes"][
+            "build_platform"
+        ].startswith("linux"):
+            job["dependencies"].update(
+                {
+                    "build-signing": job["dependent-tasks"]["build-signing"].label,
+                }
+            )
+        if job["attributes"]["build_platform"].startswith("macosx"):
+            job["dependencies"].update(
+                {"repackage": job["dependent-tasks"]["repackage"].label}
+            )
+        yield job
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by platform, etc."""
+    fields = [
+        "locales-file",
+        "locales-per-chunk",
+        "worker-type",
+        "description",
+        "run-time",
+        "docker-image",
+        "secrets",
+        "fetches.toolchain",
+        "fetches.fetch",
+        "tooltool",
+        "env",
+        "ignore-locales",
+        "mozharness.config",
+        "mozharness.options",
+        "mozharness.actions",
+        "mozharness.script",
+        "treeherder.tier",
+        "treeherder.platform",
+        "index.type",
+        "index.product",
+        "index.job-name",
+        "when.files-changed",
+    ]
+    for job in jobs:
+        job = copy_task(job)  # don't overwrite dict values here
+        for field in fields:
+            resolve_keyed_by(item=job, field=field, item_name=job["name"])
+        yield job
+
+
+@transforms.add
+def handle_artifact_prefix(config, jobs):
+    """Resolve ``artifact_prefix`` in env vars"""
+    for job in jobs:
+        artifact_prefix = get_artifact_prefix(job)
+        for k1, v1 in job.get("env", {}).items():
+            if isinstance(v1, str):
+                job["env"][k1] = v1.format(artifact_prefix=artifact_prefix)
+            elif isinstance(v1, dict):
+                for k2, v2 in v1.items():
+                    job["env"][k1][k2] = v2.format(artifact_prefix=artifact_prefix)
+        yield job
+
+
+@transforms.add
+def all_locales_attribute(config, jobs):
+    for job in jobs:
+        locales_platform = job["attributes"]["build_platform"].replace("-shippable", "")
+        locales_platform = locales_platform.replace("-pgo", "")
+        locales_with_changesets = parse_locales_file(
+            job["locales-file"], platform=locales_platform
+        )
+        locales_with_changesets = _remove_locales(
+            locales_with_changesets, to_remove=job["ignore-locales"]
+        )
+
+        locales = sorted(locales_with_changesets.keys())
+        attributes = job.setdefault("attributes", {})
+        attributes["all_locales"] = locales
+        attributes["all_locales_with_changesets"] = locales_with_changesets
+        if job.get("shipping-product"):
+            attributes["shipping_product"] = job["shipping-product"]
+        yield job
+
+
+@transforms.add
+def chunk_locales(config, jobs):
+    """Utilizes chunking for l10n stuff"""
+    for job in jobs:
+        locales_per_chunk = job.get("locales-per-chunk")
+        locales_with_changesets = job["attributes"]["all_locales_with_changesets"]
+        if locales_per_chunk:
+            chunks, remainder = divmod(len(locales_with_changesets), locales_per_chunk)
+            if remainder:
+                chunks = int(chunks + 1)
+            for this_chunk in range(1, chunks + 1):
+                chunked = copy_task(job)
+                chunked["name"] = chunked["name"].replace("/", f"-{this_chunk}/", 1)
+                chunked["mozharness"]["options"] = chunked["mozharness"].get(
+                    "options", []
+                )
+                # chunkify doesn't work with dicts
+                locales_with_changesets_as_list = sorted(
+                    locales_with_changesets.items()
+                )
+                chunked_locales = chunkify(
+                    locales_with_changesets_as_list, this_chunk, chunks
+                )
+                chunked["mozharness"]["options"].extend(
+                    [
+                        f"locale={locale}:{changeset}"
+                        for locale, changeset in chunked_locales
+                    ]
+                )
+                chunked["attributes"]["l10n_chunk"] = str(this_chunk)
+                # strip revision
+                chunked["attributes"]["chunk_locales"] = [
+                    locale for locale, _ in chunked_locales
+                ]
+
+                # add the chunk number to the TH symbol
+                chunked["treeherder"]["symbol"] = add_suffix(
+                    chunked["treeherder"]["symbol"], this_chunk
+                )
+                yield chunked
+        else:
+            job["mozharness"]["options"] = job["mozharness"].get("options", [])
+            job["mozharness"]["options"].extend(
+                [
+                    f"locale={locale}:{changeset}"
+                    for locale, changeset in sorted(locales_with_changesets.items())
+                ]
+            )
+            yield job
+
+
+transforms.add_validate(l10n_description_schema)
+
+
+@transforms.add
+def stub_installer(config, jobs):
+    for job in jobs:
+        job.setdefault("attributes", {})
+        job.setdefault("env", {})
+        if job["attributes"].get("stub-installer"):
+            job["env"].update({"USE_STUB_INSTALLER": "1"})
+        yield job
+
+
+@transforms.add
+def set_extra_config(config, jobs):
+    for job in jobs:
+        job["mozharness"].setdefault("extra-config", {})["branch"] = config.params[
+            "project"
+        ]
+        if "update-channel" in job["attributes"]:
+            job["mozharness"]["extra-config"]["update_channel"] = job["attributes"][
+                "update-channel"
+            ]
+        yield job
+
+
+@transforms.add
+def make_job_description(config, jobs):
+    for job in jobs:
+        job["mozharness"].update(
+            {
+                "using": "mozharness",
+                "job-script": "taskcluster/scripts/builder/build-l10n.sh",
+                "secrets": job.get("secrets", False),
+            }
+        )
+        job_description = {
+            "name": job["name"],
+            "worker-type": job["worker-type"],
+            "description": job["description"],
+            "run": job["mozharness"],
+            "attributes": job["attributes"],
+            "treeherder": {
+                "kind": "build",
+                "tier": job["treeherder"]["tier"],
+                "symbol": job["treeherder"]["symbol"],
+                "platform": job["treeherder"]["platform"],
+            },
+            "run-on-projects": job.get("run-on-projects")
+            if job.get("run-on-projects")
+            else [],
+        }
+        if job.get("extra"):
+            job_description["extra"] = job["extra"]
+
+        job_description["run"]["tooltool-downloads"] = job["tooltool"]
+
+        job_description["worker"] = {
+            "max-run-time": job["run-time"],
+            "chain-of-trust": True,
+        }
+        if job["worker-type"] == "b-win2012":
+            job_description["worker"]["os"] = "windows"
+            job_description["run"]["use-simple-package"] = False
+            job_description["run"]["use-magic-mh-args"] = False
+
+        if job.get("docker-image"):
+            job_description["worker"]["docker-image"] = job["docker-image"]
+
+        if job.get("fetches"):
+            job_description["fetches"] = job["fetches"]
+
+        if job.get("index"):
+            job_description["index"] = {
+                "product": job["index"]["product"],
+                "job-name": job["index"]["job-name"],
+                "type": job["index"].get("type", "generic"),
+            }
+
+        if job.get("dependencies"):
+            job_description["dependencies"] = job["dependencies"]
+        if job.get("env"):
+            job_description["worker"]["env"] = job["env"]
+        if job.get("when", {}).get("files-changed"):
+            job_description.setdefault("when", {})
+            job_description["when"]["files-changed"] = [job["locales-file"]] + job[
+                "when"
+            ]["files-changed"]
+
+        if "shipping-phase" in job:
+            job_description["shipping-phase"] = job["shipping-phase"]
+
+        if "shipping-product" in job:
+            job_description["shipping-product"] = job["shipping-product"]
+
+        yield job_description
diff --git a/taskcluster/gecko_taskgraph/transforms/mac_dummy.py b/taskcluster/gecko_taskgraph/transforms/mac_dummy.py
new file mode 100644
index 0000000000..f134ee2765
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/mac_dummy.py
@@ -0,0 +1,40 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add dependencies to dummy macosx64 tasks.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_dependencies(config, jobs):
+    for job in jobs:
+        dependencies = {}
+
+        platform = job.get("attributes", {}).get("build_platform")
+        if not platform:
+            continue
+        arm = platform.replace("macosx64", "macosx64-aarch64")
+        intel = platform.replace("macosx64", "macosx64-x64")
+        for dep_task in config.kind_dependencies_tasks.values():
+            # Weed out unwanted tasks.
+            if dep_task.attributes.get("build_platform"):
+                if dep_task.attributes["build_platform"] not in (platform, arm, intel):
+                    continue
+            # Add matching tasks to deps
+            dependencies[dep_task.label] = dep_task.label
+            # Pick one task to copy run-on-projects from
+            if (
+                dep_task.kind == "build"
+                and dep_task.attributes["build_platform"] == platform
+            ):
+                job["run-on-projects"] = dep_task.attributes.get("run_on_projects")
+
+        job.setdefault("dependencies", {}).update(dependencies)
+        job["if-dependencies"] = list(dependencies)
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/mac_notarization.py b/taskcluster/gecko_taskgraph/transforms/mac_notarization.py
new file mode 100644
index 0000000000..5591022e1b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/mac_notarization.py
@@ -0,0 +1,19 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform mac notarization tasks
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def only_level_3_notarization(config, jobs):
+    """Filter out any notarization jobs that are not level 3"""
+    for job in jobs:
+        if "notarization" in config.kind and int(config.params["level"]) != 3:
+            continue
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/mar_signing.py b/taskcluster/gecko_taskgraph/transforms/mar_signing.py
new file mode 100644
index 0000000000..d923721f45
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/mar_signing.py
@@ -0,0 +1,140 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the {partials,mar}-signing task into an actual task description.
+"""
+
+import logging
+import os
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_prefix
+from taskgraph.util.treeherder import inherit_treeherder_from_dep, join_symbol
+
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    sorted_unique_list,
+)
+from gecko_taskgraph.util.partials import get_partials_artifacts_from_params
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope_per_platform
+
+logger = logging.getLogger(__name__)
+
+SIGNING_FORMATS = {
+    "mar-signing-autograph-stage": {
+        "target.complete.mar": ["autograph_stage_mar384"],
+    },
+    "default": {
+        "target.complete.mar": ["autograph_hash_only_mar384"],
+    },
+}
+
+transforms = TransformSequence()
+
+
+def generate_partials_artifacts(job, release_history, platform, locale=None):
+    artifact_prefix = get_artifact_prefix(job)
+    if locale:
+        artifact_prefix = f"{artifact_prefix}/{locale}"
+    else:
+        locale = "en-US"
+
+    artifacts = get_partials_artifacts_from_params(release_history, platform, locale)
+
+    upstream_artifacts = [
+        {
+            "taskId": {"task-reference": "<partials>"},
+            "taskType": "partials",
+            "paths": [f"{artifact_prefix}/{path}" for path, version in artifacts],
+            "formats": ["autograph_hash_only_mar384"],
+        }
+    ]
+
+    return upstream_artifacts
+
+
+def generate_complete_artifacts(job, kind):
+    upstream_artifacts = []
+    if kind not in SIGNING_FORMATS:
+        kind = "default"
+    for artifact in job.attributes["release_artifacts"]:
+        basename = os.path.basename(artifact)
+        if basename in SIGNING_FORMATS[kind]:
+            upstream_artifacts.append(
+                {
+                    "taskId": {"task-reference": f"<{job.kind}>"},
+                    "taskType": "build",
+                    "paths": [artifact],
+                    "formats": SIGNING_FORMATS[kind][basename],
+                }
+            )
+
+    return upstream_artifacts
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        locale = dep_job.attributes.get("locale")
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault(
+            "symbol", join_symbol(job.get("treeherder-group", "ms"), locale or "N")
+        )
+
+        label = job.get("label", f"{config.kind}-{dep_job.label}")
+
+        dependencies = {dep_job.kind: dep_job.label}
+        signing_dependencies = dep_job.dependencies
+        # This is so we get the build task etc in our dependencies to
+        # have better beetmover support.
+        dependencies.update(signing_dependencies)
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes["required_signoffs"] = sorted_unique_list(
+            attributes.get("required_signoffs", []), job.pop("required_signoffs")
+        )
+        attributes["shipping_phase"] = job["shipping-phase"]
+        if locale:
+            attributes["locale"] = locale
+
+        build_platform = attributes.get("build_platform")
+        if config.kind == "partials-signing":
+            upstream_artifacts = generate_partials_artifacts(
+                dep_job, config.params["release_history"], build_platform, locale
+            )
+        else:
+            upstream_artifacts = generate_complete_artifacts(dep_job, config.kind)
+
+        is_shippable = job.get(
+            "shippable", dep_job.attributes.get("shippable")  # First check current job
+        )  # Then dep job for 'shippable'
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_shippable, config
+        )
+
+        scopes = [signing_cert_scope]
+
+        task = {
+            "label": label,
+            "description": "{} {}".format(
+                dep_job.description, job["description-suffix"]
+            ),
+            "worker-type": job.get("worker-type", "linux-signing"),
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+                "max-run-time": 3600,
+            },
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "scopes": scopes,
+            "run-on-projects": job.get(
+                "run-on-projects", dep_job.attributes.get("run_on_projects")
+            ),
+            "treeherder": treeherder,
+        }
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/maybe_release.py b/taskcluster/gecko_taskgraph/transforms/maybe_release.py
new file mode 100644
index 0000000000..08a066001a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/maybe_release.py
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        for key in ["worker-type", "scopes"]:
+            resolve_keyed_by(
+                job,
+                key,
+                item_name=job["name"],
+                **{"release-level": release_level(config.params["project"])}
+            )
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/merge_automation.py b/taskcluster/gecko_taskgraph/transforms/merge_automation.py
new file mode 100644
index 0000000000..ca5f3b6bde
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/merge_automation.py
@@ -0,0 +1,81 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the update generation task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def handle_keyed_by(config, tasks):
+    """Resolve fields that can be keyed by platform, etc."""
+    if "merge_config" not in config.params:
+        return
+    merge_config = config.params["merge_config"]
+    fields = [
+        "worker.push",
+        "worker-type",
+        "worker.l10n-bump-info",
+        "worker.source-repo",
+    ]
+    for task in tasks:
+        for field in fields:
+            resolve_keyed_by(
+                task,
+                field,
+                item_name=task["name"],
+                **{
+                    "project": config.params["project"],
+                    "release-type": config.params["release_type"],
+                    "behavior": merge_config["behavior"],
+                }
+            )
+        yield task
+
+
+@transforms.add
+def update_labels(config, tasks):
+    for task in tasks:
+        merge_config = config.params["merge_config"]
+        task["label"] = "merge-{}".format(merge_config["behavior"])
+        treeherder = task.get("treeherder", {})
+        treeherder["symbol"] = "Rel({})".format(merge_config["behavior"])
+        task["treeherder"] = treeherder
+        yield task
+
+
+@transforms.add
+def add_payload_config(config, tasks):
+    for task in tasks:
+        if "merge_config" not in config.params:
+            break
+        merge_config = config.params["merge_config"]
+        worker = task["worker"]
+        worker["merge-info"] = config.graph_config["merge-automation"]["behaviors"][
+            merge_config["behavior"]
+        ]
+
+        if "l10n-bump-info" in worker and worker["l10n-bump-info"] is None:
+            del worker["l10n-bump-info"]
+
+        # Override defaults, useful for testing.
+        for field in [
+            "from-repo",
+            "from-branch",
+            "to-repo",
+            "to-branch",
+            "fetch-version-from",
+        ]:
+            if merge_config.get(field):
+                worker["merge-info"][field] = merge_config[field]
+
+        worker["force-dry-run"] = merge_config["force-dry-run"]
+        worker["ssh-user"] = merge_config.get("ssh-user-alias", "merge_user")
+        if merge_config.get("push"):
+            worker["push"] = merge_config["push"]
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/name_sanity.py b/taskcluster/gecko_taskgraph/transforms/name_sanity.py
new file mode 100644
index 0000000000..856f4f82be
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/name_sanity.py
@@ -0,0 +1,45 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Generate labels for tasks without names, consistently.
+Uses attributes from `primary-dependency`.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_label(config, jobs):
+    """Generate a sane label for a new task constructed from a dependency
+    Using attributes from the dependent job and the current task kind"""
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attr = dep_job.attributes.get
+
+        if attr("locale", job.get("locale")):
+            template = "{kind}-{locale}-{build_platform}/{build_type}"
+        elif attr("l10n_chunk"):
+            template = "{kind}-{build_platform}-{l10n_chunk}/{build_type}"
+        elif config.kind.startswith("release-eme-free") or config.kind.startswith(
+            "release-partner-repack"
+        ):
+            suffix = job.get("extra", {}).get("repack_suffix", None) or job.get(
+                "extra", {}
+            ).get("repack_id", None)
+            template = "{kind}-{build_platform}"
+            if suffix:
+                template += "-{}".format(suffix.replace("/", "-"))
+        else:
+            template = "{kind}-{build_platform}/{build_type}"
+        job["label"] = template.format(
+            kind=config.kind,
+            build_platform=attr("build_platform"),
+            build_type=attr("build_type"),
+            locale=attr("locale", job.get("locale", "")),  # Locale can be absent
+            l10n_chunk=attr("l10n_chunk", ""),  # Can be empty
+        )
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/openh264.py b/taskcluster/gecko_taskgraph/transforms/openh264.py
new file mode 100644
index 0000000000..f41215d20b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/openh264.py
@@ -0,0 +1,26 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+This transform is used to help populate mozharness options for openh264 jobs
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_mh_options(config, jobs):
+    """
+    This transform sets the 'openh264_rev' attribute.
+    """
+    for job in jobs:
+        repo = job.pop("repo")
+        rev = job.pop("revision")
+        attributes = job.setdefault("attributes", {})
+        attributes["openh264_rev"] = rev
+        run = job.setdefault("run", {})
+        options = run.setdefault("options", [])
+        options.extend([f"repo={repo}", f"rev={rev}"])
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/openh264_signing.py b/taskcluster/gecko_taskgraph/transforms/openh264_signing.py
new file mode 100644
index 0000000000..dfffc7cc17
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/openh264_signing.py
@@ -0,0 +1,109 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import inherit_treeherder_from_dep
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope_per_platform
+
+transforms = TransformSequence()
+
+signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("extra"): object,
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+transforms.add_validate(signing_description_schema)
+
+
+@transforms.add
+def make_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+        build_platform = dep_job.attributes.get("build_platform")
+        is_nightly = True  # cert_scope_per_platform uses this to choose the right cert
+
+        description = (
+            "Signing of OpenH264 Binaries for '"
+            "{build_platform}/{build_type}'".format(
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        # we have a genuine repackage job as our parent
+        dependencies = {"openh264": dep_job.label}
+
+        my_attributes = copy_attributes_from_dependent_job(dep_job)
+
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_nightly, config
+        )
+
+        scopes = [signing_cert_scope]
+        worker_type = "linux-signing"
+        worker = {
+            "implementation": "scriptworker-signing",
+            "max-run-time": 3600,
+        }
+        rev = attributes["openh264_rev"]
+        upstream_artifact = {
+            "taskId": {"task-reference": "<openh264>"},
+            "taskType": "build",
+        }
+
+        if "win" in build_platform:
+            # job['primary-dependency'].task['payload']['command']
+            upstream_artifact["formats"] = ["autograph_authenticode_sha2"]
+        elif "mac" in build_platform:
+            upstream_artifact["formats"] = ["mac_single_file"]
+            upstream_artifact["singleFileGlobs"] = ["libgmpopenh264.dylib"]
+            worker_type = "mac-signing"
+            worker["mac-behavior"] = "mac_notarize_single_file"
+        else:
+            upstream_artifact["formats"] = ["autograph_gpg"]
+
+        upstream_artifact["paths"] = [
+            f"private/openh264/openh264-{build_platform}-{rev}.zip",
+        ]
+        worker["upstream-artifacts"] = [upstream_artifact]
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault(
+            "symbol",
+            _generate_treeherder_symbol(
+                dep_job.task.get("extra", {}).get("treeherder", {}).get("symbol")
+            ),
+        )
+
+        task = {
+            "label": job["label"],
+            "description": description,
+            "worker-type": worker_type,
+            "worker": worker,
+            "scopes": scopes,
+            "dependencies": dependencies,
+            "attributes": my_attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+        }
+
+        yield task
+
+
+def _generate_treeherder_symbol(build_symbol):
+    symbol = build_symbol + "s"
+    return symbol
diff --git a/taskcluster/gecko_taskgraph/transforms/partials.py b/taskcluster/gecko_taskgraph/transforms/partials.py
new file mode 100644
index 0000000000..267739cfc3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/partials.py
@@ -0,0 +1,172 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the partials task into an actual task description.
+"""
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_prefix
+from taskgraph.util.treeherder import inherit_treeherder_from_dep
+
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.partials import get_builds
+from gecko_taskgraph.util.platforms import architecture
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+def _generate_task_output_files(job, filenames, locale=None):
+    locale_output_path = f"{locale}/" if locale else ""
+    artifact_prefix = get_artifact_prefix(job)
+
+    data = list()
+    for filename in filenames:
+        data.append(
+            {
+                "type": "file",
+                "path": f"/home/worker/artifacts/{filename}",
+                "name": f"{artifact_prefix}/{locale_output_path}{filename}",
+            }
+        )
+    data.append(
+        {
+            "type": "file",
+            "path": "/home/worker/artifacts/manifest.json",
+            "name": f"{artifact_prefix}/{locale_output_path}manifest.json",
+        }
+    )
+    return data
+
+
+def identify_desired_signing_keys(project, product):
+    if project in ["mozilla-central", "comm-central", "oak"]:
+        return "nightly"
+    if project == "mozilla-beta":
+        if product == "devedition":
+            return "nightly"
+        return "release"
+    if (
+        project in ["mozilla-release", "comm-beta"]
+        or project.startswith("mozilla-esr")
+        or project.startswith("comm-esr")
+    ):
+        return "release"
+    return "dep1"
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    # If no balrog release history, then don't generate partials
+    if not config.params.get("release_history"):
+        return
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault("symbol", "p(N)")
+
+        label = job.get("label", f"partials-{dep_job.label}")
+
+        dependencies = {dep_job.kind: dep_job.label}
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        locale = dep_job.attributes.get("locale")
+        if locale:
+            attributes["locale"] = locale
+            treeherder["symbol"] = f"p({locale})"
+        attributes["shipping_phase"] = job["shipping-phase"]
+
+        build_locale = locale or "en-US"
+
+        build_platform = attributes["build_platform"]
+        builds = get_builds(
+            config.params["release_history"], build_platform, build_locale
+        )
+
+        # If the list is empty there's no available history for this platform
+        # and locale combination, so we can't build any partials.
+        if not builds:
+            continue
+
+        extra = {"funsize": {"partials": list()}}
+        update_number = 1
+
+        locale_suffix = ""
+        if locale:
+            locale_suffix = f"{locale}/"
+        artifact_path = "<{}/{}/{}target.complete.mar>".format(
+            dep_job.kind,
+            get_artifact_prefix(dep_job),
+            locale_suffix,
+        )
+        for build in sorted(builds):
+            partial_info = {
+                "locale": build_locale,
+                "from_mar": builds[build]["mar_url"],
+                "to_mar": {"artifact-reference": artifact_path},
+                "branch": config.params["project"],
+                "update_number": update_number,
+                "dest_mar": build,
+            }
+            if "product" in builds[build]:
+                partial_info["product"] = builds[build]["product"]
+            if "previousVersion" in builds[build]:
+                partial_info["previousVersion"] = builds[build]["previousVersion"]
+            if "previousBuildNumber" in builds[build]:
+                partial_info["previousBuildNumber"] = builds[build][
+                    "previousBuildNumber"
+                ]
+            extra["funsize"]["partials"].append(partial_info)
+            update_number += 1
+
+        level = config.params["level"]
+
+        worker = {
+            "artifacts": _generate_task_output_files(dep_job, builds.keys(), locale),
+            "implementation": "docker-worker",
+            "docker-image": {"in-tree": "funsize-update-generator"},
+            "os": "linux",
+            "max-run-time": 3600 if "asan" in dep_job.label else 1800,
+            "chain-of-trust": True,
+            "taskcluster-proxy": True,
+            "env": {
+                "SIGNING_CERT": identify_desired_signing_keys(
+                    config.params["project"], config.params["release_product"]
+                ),
+                "EXTRA_PARAMS": f"--arch={architecture(build_platform)}",
+                "MAR_CHANNEL_ID": attributes["mar-channel-id"],
+            },
+        }
+        if release_level(config.params["project"]) == "staging":
+            worker["env"]["FUNSIZE_ALLOW_STAGING_PREFIXES"] = "true"
+
+        task = {
+            "label": label,
+            "description": f"{dep_job.description} Partials",
+            "worker-type": "b-linux-gcp",
+            "dependencies": dependencies,
+            "scopes": [],
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "extra": extra,
+            "worker": worker,
+        }
+
+        # We only want caching on linux/windows due to bug 1436977
+        if int(level) == 3 and any(
+            [build_platform.startswith(prefix) for prefix in ["linux", "win"]]
+        ):
+            task["scopes"].append(
+                "auth:aws-s3:read-write:tc-gp-private-1d-us-east-1/releng/mbsdiff-cache/"
+            )
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/partner_attribution.py b/taskcluster/gecko_taskgraph/transforms/partner_attribution.py
new file mode 100644
index 0000000000..0bd5e0d141
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/partner_attribution.py
@@ -0,0 +1,129 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the partner attribution task into an actual task description.
+"""
+
+
+import json
+import logging
+from collections import defaultdict
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.partners import (
+    apply_partner_priority,
+    check_if_partners_enabled,
+    generate_attribution_code,
+    get_partner_config_by_kind,
+)
+
+log = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+transforms.add(check_if_partners_enabled)
+transforms.add(apply_partner_priority)
+
+
+@transforms.add
+def add_command_arguments(config, tasks):
+    enabled_partners = config.params.get("release_partners")
+    dependencies = {}
+    fetches = defaultdict(set)
+    attributions = []
+    release_artifacts = []
+    attribution_config = get_partner_config_by_kind(config, config.kind)
+
+    for partner_config in attribution_config.get("configs", []):
+        # we might only be interested in a subset of all partners, eg for a respin
+        if enabled_partners and partner_config["campaign"] not in enabled_partners:
+            continue
+        attribution_code = generate_attribution_code(
+            attribution_config["defaults"], partner_config
+        )
+        for platform in partner_config["platforms"]:
+            stage_platform = platform.replace("-shippable", "")
+            for locale in partner_config["locales"]:
+                # find the upstream, throw away locales we don't have, somehow. Skip ?
+                if locale == "en-US":
+                    upstream_label = "repackage-signing-{platform}/opt".format(
+                        platform=platform
+                    )
+                    upstream_artifact = "target.installer.exe"
+                else:
+                    upstream_label = (
+                        "repackage-signing-l10n-{locale}-{platform}/opt".format(
+                            locale=locale, platform=platform
+                        )
+                    )
+                    upstream_artifact = "{locale}/target.installer.exe".format(
+                        locale=locale
+                    )
+                if upstream_label not in config.kind_dependencies_tasks:
+                    raise Exception(f"Can't find upstream task for {platform} {locale}")
+                upstream = config.kind_dependencies_tasks[upstream_label]
+
+                # set the dependencies to just what we need rather than all of l10n
+                dependencies.update({upstream.label: upstream.label})
+
+                fetches[upstream_label].add((upstream_artifact, stage_platform, locale))
+
+                artifact_part = "{platform}/{locale}/target.installer.exe".format(
+                    platform=stage_platform, locale=locale
+                )
+                artifact = (
+                    "releng/partner/{partner}/{sub_partner}/{artifact_part}".format(
+                        partner=partner_config["campaign"],
+                        sub_partner=partner_config["content"],
+                        artifact_part=artifact_part,
+                    )
+                )
+                # config for script
+                # TODO - generalise input & output ??
+                #  add releng/partner prefix via get_artifact_prefix..()
+                attributions.append(
+                    {
+                        "input": f"/builds/worker/fetches/{artifact_part}",
+                        "output": f"/builds/worker/artifacts/{artifact}",
+                        "attribution": attribution_code,
+                    }
+                )
+                release_artifacts.append(artifact)
+
+    # bail-out early if we don't have any attributions to do
+    if not attributions:
+        return
+
+    for task in tasks:
+        worker = task.get("worker", {})
+        worker["chain-of-trust"] = True
+
+        task.setdefault("dependencies", {}).update(dependencies)
+        task.setdefault("fetches", {})
+        for upstream_label, upstream_artifacts in fetches.items():
+            task["fetches"][upstream_label] = [
+                {
+                    "artifact": upstream_artifact,
+                    "dest": "{platform}/{locale}".format(
+                        platform=platform, locale=locale
+                    ),
+                    "extract": False,
+                    "verify-hash": True,
+                }
+                for upstream_artifact, platform, locale in upstream_artifacts
+            ]
+        worker.setdefault("env", {})["ATTRIBUTION_CONFIG"] = json.dumps(
+            attributions, sort_keys=True
+        )
+        worker["artifacts"] = [
+            {
+                "name": "releng/partner",
+                "path": "/builds/worker/artifacts/releng/partner",
+                "type": "directory",
+            }
+        ]
+        task.setdefault("attributes", {})["release_artifacts"] = release_artifacts
+        task["label"] = config.kind
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/partner_attribution_beetmover.py b/taskcluster/gecko_taskgraph/transforms/partner_attribution_beetmover.py
new file mode 100644
index 0000000000..b2c435dd81
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/partner_attribution_beetmover.py
@@ -0,0 +1,202 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+from collections import defaultdict
+from copy import deepcopy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.partners import (
+    apply_partner_priority,
+    get_partner_config_by_kind,
+)
+from gecko_taskgraph.util.scriptworker import (
+    add_scope_prefix,
+    get_beetmover_bucket_scope,
+)
+
+beetmover_description_schema = schema.extend(
+    {
+        # depname is used in taskref's to identify the taskID of the unsigned things
+        Required("depname", default="build"): str,
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Optional("label"): str,
+        Required("partner-bucket-scope"): optionally_keyed_by("release-level", str),
+        Required("partner-public-path"): Any(None, str),
+        Required("partner-private-path"): Any(None, str),
+        Optional("extra"): object,
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("priority"): task_description_schema["priority"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(beetmover_description_schema)
+transforms.add(apply_partner_priority)
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "partner-bucket-scope",
+            item_name=job["label"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        yield job
+
+
+@transforms.add
+def split_public_and_private(config, jobs):
+    # we need to separate private vs public destinations because beetmover supports one
+    # in a single task. Only use a single task for each type though.
+    partner_config = get_partner_config_by_kind(config, config.kind)
+    for job in jobs:
+        upstream_artifacts = job["primary-dependency"].attributes.get(
+            "release_artifacts"
+        )
+        attribution_task_ref = "<{}>".format(job["primary-dependency"].label)
+        prefix = get_artifact_prefix(job["primary-dependency"])
+        artifacts = defaultdict(list)
+        for artifact in upstream_artifacts:
+            partner, sub_partner, platform, locale, _ = artifact.replace(
+                prefix + "/", ""
+            ).split("/", 4)
+            destination = "private"
+            this_config = [
+                p
+                for p in partner_config["configs"]
+                if (p["campaign"] == partner and p["content"] == sub_partner)
+            ]
+            if this_config[0].get("upload_to_candidates"):
+                destination = "public"
+            artifacts[destination].append(
+                (artifact, partner, sub_partner, platform, locale)
+            )
+
+        action_scope = add_scope_prefix(config, "beetmover:action:push-to-partner")
+        public_bucket_scope = get_beetmover_bucket_scope(config)
+        partner_bucket_scope = add_scope_prefix(config, job["partner-bucket-scope"])
+        repl_dict = {
+            "build_number": config.params["build_number"],
+            "release_partner_build_number": config.params[
+                "release_partner_build_number"
+            ],
+            "version": config.params["version"],
+            "partner": "{partner}",  # we'll replace these later, per artifact
+            "subpartner": "{subpartner}",
+            "platform": "{platform}",
+            "locale": "{locale}",
+        }
+        for destination, destination_artifacts in artifacts.items():
+            this_job = deepcopy(job)
+
+            if destination == "public":
+                this_job["scopes"] = [public_bucket_scope, action_scope]
+                this_job["partner_public"] = True
+            else:
+                this_job["scopes"] = [partner_bucket_scope, action_scope]
+                this_job["partner_public"] = False
+
+            partner_path_key = f"partner-{destination}-path"
+            partner_path = this_job[partner_path_key].format(**repl_dict)
+            this_job.setdefault("worker", {})[
+                "upstream-artifacts"
+            ] = generate_upstream_artifacts(
+                attribution_task_ref, destination_artifacts, partner_path
+            )
+
+            yield this_job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        attributes = dep_job.attributes
+        build_platform = attributes.get("build_platform")
+        if not build_platform:
+            raise Exception("Cannot find build platform!")
+
+        label = config.kind
+        description = "Beetmover for partner attribution"
+        if job["partner_public"]:
+            label = f"{label}-public"
+            description = f"{description} public"
+        else:
+            label = f"{label}-private"
+            description = f"{description} private"
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        task = {
+            "label": label,
+            "description": description,
+            "dependencies": {dep_job.kind: dep_job.label},
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "shipping-phase": job["shipping-phase"],
+            "shipping-product": job.get("shipping-product"),
+            "partner_public": job["partner_public"],
+            "worker": job["worker"],
+            "scopes": job["scopes"],
+        }
+        # we may have reduced the priority for partner jobs, otherwise task.py will set it
+        if job.get("priority"):
+            task["priority"] = job["priority"]
+
+        yield task
+
+
+def generate_upstream_artifacts(attribution_task, artifacts, partner_path):
+    upstream_artifacts = []
+    for artifact, partner, subpartner, platform, locale in artifacts:
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": attribution_task},
+                "taskType": "repackage",
+                "paths": [artifact],
+                "locale": partner_path.format(
+                    partner=partner,
+                    subpartner=subpartner,
+                    platform=platform,
+                    locale=locale,
+                ),
+            }
+        )
+
+    if not upstream_artifacts:
+        raise Exception("Couldn't find any upstream artifacts.")
+
+    return upstream_artifacts
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        job["worker-type"] = "beetmover"
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "partner-public": job["partner_public"],
+        }
+        job["worker"].update(worker)
+        del job["partner_public"]
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/partner_repack.py b/taskcluster/gecko_taskgraph/transforms/partner_repack.py
new file mode 100644
index 0000000000..d164c10a59
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/partner_repack.py
@@ -0,0 +1,136 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the partner repack task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.partners import (
+    apply_partner_priority,
+    check_if_partners_enabled,
+    get_partner_config_by_kind,
+    get_partner_url_config,
+    get_repack_ids_by_platform,
+)
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+transforms.add(check_if_partners_enabled)
+transforms.add(apply_partner_priority)
+
+
+@transforms.add
+def skip_unnecessary_platforms(config, tasks):
+    for task in tasks:
+        if config.kind == "release-partner-repack":
+            platform = task["attributes"]["build_platform"]
+            repack_ids = get_repack_ids_by_platform(config, platform)
+            if not repack_ids:
+                continue
+        yield task
+
+
+@transforms.add
+def remove_mac_dependency(config, tasks):
+    """Remove mac dependency depending on current level
+    to accomodate for mac notarization not running on level 1
+    """
+    level = int(config.params.get("level", 0))
+    for task in tasks:
+        if "macosx" not in task["attributes"]["build_platform"]:
+            yield task
+            continue
+        skipped_kind = "mac-signing" if level == 3 else "mac-notarization"
+        for dep_label in list(task["dependencies"].keys()):
+            if skipped_kind in dep_label:
+                del task["dependencies"][dep_label]
+        yield task
+
+
+@transforms.add
+def populate_repack_manifests_url(config, tasks):
+    for task in tasks:
+        partner_url_config = get_partner_url_config(config.params, config.graph_config)
+
+        for k in partner_url_config:
+            if config.kind.startswith(k):
+                task["worker"].setdefault("env", {})[
+                    "REPACK_MANIFESTS_URL"
+                ] = partner_url_config[k]
+                break
+        else:
+            raise Exception("Can't find partner REPACK_MANIFESTS_URL")
+
+        for property in ("limit-locales",):
+            property = f"extra.{property}"
+            resolve_keyed_by(
+                task,
+                property,
+                property,
+                **{"release-level": release_level(config.params["project"])},
+            )
+
+        if task["worker"]["env"]["REPACK_MANIFESTS_URL"].startswith("git@"):
+            task.setdefault("scopes", []).append(
+                "secrets:get:project/releng/gecko/build/level-{level}/partner-github-ssh".format(
+                    **config.params
+                )
+            )
+
+        yield task
+
+
+@transforms.add
+def make_label(config, tasks):
+    for task in tasks:
+        task["label"] = "{}-{}".format(config.kind, task["name"])
+        yield task
+
+
+@transforms.add
+def add_command_arguments(config, tasks):
+    release_config = get_release_config(config)
+
+    # staging releases - pass reduced set of locales to the repacking script
+    all_locales = set()
+    partner_config = get_partner_config_by_kind(config, config.kind)
+    for partner in partner_config.values():
+        for sub_partner in partner.values():
+            all_locales.update(sub_partner.get("locales", []))
+
+    for task in tasks:
+        # add the MOZHARNESS_OPTIONS, eg version=61.0, build-number=1, platform=win64
+        if not task["attributes"]["build_platform"].endswith("-shippable"):
+            raise Exception(
+                "Unexpected partner repack platform: {}".format(
+                    task["attributes"]["build_platform"],
+                ),
+            )
+        platform = task["attributes"]["build_platform"].partition("-shippable")[0]
+        task["run"]["options"] = [
+            "version={}".format(release_config["version"]),
+            "build-number={}".format(release_config["build_number"]),
+            f"platform={platform}",
+        ]
+        if task["extra"]["limit-locales"]:
+            for locale in all_locales:
+                task["run"]["options"].append(f"limit-locale={locale}")
+        if "partner" in config.kind and config.params["release_partners"]:
+            for partner in config.params["release_partners"]:
+                task["run"]["options"].append(f"partner={partner}")
+
+        # The upstream taskIds are stored a special environment variable, because we want to use
+        # task-reference's to resolve dependencies, but the string handling of MOZHARNESS_OPTIONS
+        # blocks that. It's space-separated string of ids in the end.
+        task["worker"]["env"]["UPSTREAM_TASKIDS"] = {
+            "task-reference": " ".join([f"<{dep}>" for dep in task["dependencies"]])
+        }
+
+        # Forward the release type for bouncer product construction
+        task["worker"]["env"]["RELEASE_TYPE"] = config.params["release_type"]
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/partner_signing.py b/taskcluster/gecko_taskgraph/transforms/partner_signing.py
new file mode 100644
index 0000000000..c9b6b7a8cc
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/partner_signing.py
@@ -0,0 +1,66 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.partners import get_partner_config_by_kind
+from gecko_taskgraph.util.signed_artifacts import (
+    generate_specifications_of_artifacts_to_sign,
+)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_mac_label(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        if "mac-notarization" in config.kind:
+            default_label = dep_job.label.replace("mac-signing", "mac-notarization")
+            job.setdefault("label", default_label)
+        assert job["label"] != dep_job.label, "Unable to determine label for {}".format(
+            config.kind
+        )
+        yield job
+
+
+@transforms.add
+def define_upstream_artifacts(config, jobs):
+    partner_configs = get_partner_config_by_kind(config, config.kind)
+    if not partner_configs:
+        return
+
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        job["depname"] = dep_job.label
+        job["attributes"] = copy_attributes_from_dependent_job(dep_job)
+
+        repack_ids = job["extra"]["repack_ids"]
+        artifacts_specifications = generate_specifications_of_artifacts_to_sign(
+            config,
+            job,
+            keep_locale_template=True,
+            kind=config.kind,
+        )
+        task_type = "build"
+        if "notarization" in job["depname"] or "mac-signing" in job["depname"]:
+            task_type = "scriptworker"
+        job["upstream-artifacts"] = [
+            {
+                "taskId": {"task-reference": f"<{dep_job.kind}>"},
+                "taskType": task_type,
+                "paths": [
+                    path_template.format(locale=repack_id)
+                    for path_template in spec["artifacts"]
+                    for repack_id in repack_ids
+                ],
+                "formats": spec["formats"],
+            }
+            for spec in artifacts_specifications
+        ]
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/per_platform_dummy.py b/taskcluster/gecko_taskgraph/transforms/per_platform_dummy.py
new file mode 100644
index 0000000000..5237f4f281
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/per_platform_dummy.py
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def one_task_per_product_and_platform(config, jobs):
+    unique_products_and_platforms = set()
+    for job in jobs:
+        dep_task = job["primary-dependency"]
+        if "primary-dependency" in job:
+            del job["primary-dependency"]
+        product = dep_task.attributes.get("shipping_product")
+        platform = dep_task.attributes.get("build_platform")
+        if (product, platform) not in unique_products_and_platforms:
+            attr_denylist = ("l10n_chunk", "locale", "artifact_map", "artifact_prefix")
+            attributes = copy_attributes_from_dependent_job(
+                dep_task, denylist=attr_denylist
+            )
+            attributes.update(job.get("attributes", {}))
+            job["attributes"] = attributes
+            job["name"] = f"{product}-{platform}"
+            yield job
+            unique_products_and_platforms.add((product, platform))
diff --git a/taskcluster/gecko_taskgraph/transforms/perftest.py b/taskcluster/gecko_taskgraph/transforms/perftest.py
new file mode 100644
index 0000000000..5c579b48b5
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/perftest.py
@@ -0,0 +1,351 @@
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+This transform passes options from `mach perftest` to the corresponding task.
+"""
+
+
+import json
+from copy import deepcopy
+from datetime import date, timedelta
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import join_symbol, split_symbol
+from voluptuous import Any, Extra, Optional
+
+transforms = TransformSequence()
+
+
+perftest_description_schema = Schema(
+    {
+        # The test names and the symbols to use for them: [test-symbol, test-path]
+        Optional("perftest"): [[str]],
+        # Metrics to gather for the test. These will be merged
+        # with options specified through perftest-perfherder-global
+        Optional("perftest-metrics"): optionally_keyed_by(
+            "perftest",
+            Any(
+                [str],
+                {str: Any(None, {str: Any(None, str, [str])})},
+            ),
+        ),
+        # Perfherder data options that will be applied to
+        # all metrics gathered.
+        Optional("perftest-perfherder-global"): optionally_keyed_by(
+            "perftest", {str: Any(None, str, [str])}
+        ),
+        # Extra options to add to the test's command
+        Optional("perftest-extra-options"): optionally_keyed_by("perftest", [str]),
+        # Variants of the test to make based on extra browsertime
+        # arguments. Expecting:
+        #    [variant-suffix, options-to-use]
+        # If variant-suffix is `null` then the options will be added
+        # to the existing task. Otherwise, a new variant is created
+        # with the given suffix and with its options replaced.
+        Optional("perftest-btime-variants"): optionally_keyed_by(
+            "perftest", [[Any(None, str)]]
+        ),
+        # These options will be parsed in the next schemas
+        Extra: object,
+    }
+)
+
+
+transforms.add_validate(perftest_description_schema)
+
+
+@transforms.add
+def split_tests(config, jobs):
+    for job in jobs:
+        if job.get("perftest") is None:
+            yield job
+            continue
+
+        for test_symbol, test_name in job.pop("perftest"):
+            job_new = deepcopy(job)
+
+            job_new["perftest"] = test_symbol
+            job_new["name"] += "-" + test_symbol
+            job_new["treeherder"]["symbol"] = job["treeherder"]["symbol"].format(
+                symbol=test_symbol
+            )
+            job_new["run"]["command"] = job["run"]["command"].replace(
+                "{perftest_testname}", test_name
+            )
+
+            yield job_new
+
+
+@transforms.add
+def handle_keyed_by_perftest(config, jobs):
+    fields = ["perftest-metrics", "perftest-extra-options", "perftest-btime-variants"]
+    for job in jobs:
+        if job.get("perftest") is None:
+            yield job
+            continue
+
+        for field in fields:
+            resolve_keyed_by(job, field, item_name=job["name"])
+
+        job.pop("perftest")
+        yield job
+
+
+@transforms.add
+def parse_perftest_metrics(config, jobs):
+    """Parse the metrics into a dictionary immediately.
+
+    This way we can modify the extraOptions field (and others) entry through the
+    transforms that come later. The metrics aren't formatted until the end of the
+    transforms.
+    """
+    for job in jobs:
+        if job.get("perftest-metrics") is None:
+            yield job
+            continue
+        perftest_metrics = job.pop("perftest-metrics")
+
+        # If perftest metrics is a string, split it up first
+        if isinstance(perftest_metrics, list):
+            new_metrics_info = [{"name": metric} for metric in perftest_metrics]
+        else:
+            new_metrics_info = []
+            for metric, options in perftest_metrics.items():
+                entry = {"name": metric}
+                entry.update(options)
+                new_metrics_info.append(entry)
+
+        job["perftest-metrics"] = new_metrics_info
+        yield job
+
+
+@transforms.add
+def split_perftest_variants(config, jobs):
+    for job in jobs:
+        if job.get("variants") is None:
+            yield job
+            continue
+
+        for variant in job.pop("variants"):
+            job_new = deepcopy(job)
+
+            group, symbol = split_symbol(job_new["treeherder"]["symbol"])
+            group += "-" + variant
+            job_new["treeherder"]["symbol"] = join_symbol(group, symbol)
+            job_new["name"] += "-" + variant
+            job_new.setdefault("perftest-perfherder-global", {}).setdefault(
+                "extraOptions", []
+            ).append(variant)
+            job_new[variant] = True
+
+            yield job_new
+
+        yield job
+
+
+@transforms.add
+def split_btime_variants(config, jobs):
+    for job in jobs:
+        if job.get("perftest-btime-variants") is None:
+            yield job
+            continue
+
+        variants = job.pop("perftest-btime-variants")
+        if not variants:
+            yield job
+            continue
+
+        yield_existing = False
+        for suffix, options in variants:
+            if suffix is None:
+                # Append options to the existing job
+                job.setdefault("perftest-btime-variants", []).append(options)
+                yield_existing = True
+            else:
+                job_new = deepcopy(job)
+                group, symbol = split_symbol(job_new["treeherder"]["symbol"])
+                symbol += "-" + suffix
+                job_new["treeherder"]["symbol"] = join_symbol(group, symbol)
+                job_new["name"] += "-" + suffix
+                job_new.setdefault("perftest-perfherder-global", {}).setdefault(
+                    "extraOptions", []
+                ).append(suffix)
+                # Replace the existing options with the new ones
+                job_new["perftest-btime-variants"] = [options]
+                yield job_new
+
+        # The existing job has been modified so we should also return it
+        if yield_existing:
+            yield job
+
+
+@transforms.add
+def setup_http3_tests(config, jobs):
+    for job in jobs:
+        if job.get("http3") is None or not job.pop("http3"):
+            yield job
+            continue
+        job.setdefault("perftest-btime-variants", []).append(
+            "firefox.preference=network.http.http3.enable:true"
+        )
+        yield job
+
+
+@transforms.add
+def setup_perftest_metrics(config, jobs):
+    for job in jobs:
+        if job.get("perftest-metrics") is None:
+            yield job
+            continue
+        perftest_metrics = job.pop("perftest-metrics")
+
+        # Options to apply to each metric
+        global_options = job.pop("perftest-perfherder-global", {})
+        for metric_info in perftest_metrics:
+            for opt, val in global_options.items():
+                if isinstance(val, list) and opt in metric_info:
+                    metric_info[opt].extend(val)
+                elif not (isinstance(val, list) and len(val) == 0):
+                    metric_info[opt] = val
+
+        quote_escape = '\\"'
+        if "win" in job.get("platform", ""):
+            # Escaping is a bit different on windows platforms
+            quote_escape = '\\\\\\"'
+
+        job["run"]["command"] = job["run"]["command"].replace(
+            "{perftest_metrics}",
+            " ".join(
+                [
+                    ",".join(
+                        [
+                            ":".join(
+                                [
+                                    option,
+                                    str(value)
+                                    .replace(" ", "")
+                                    .replace("'", quote_escape),
+                                ]
+                            )
+                            for option, value in metric_info.items()
+                        ]
+                    )
+                    for metric_info in perftest_metrics
+                ]
+            ),
+        )
+
+        yield job
+
+
+@transforms.add
+def setup_perftest_browsertime_variants(config, jobs):
+    for job in jobs:
+        if job.get("perftest-btime-variants") is None:
+            yield job
+            continue
+
+        job["run"]["command"] += " --browsertime-extra-options %s" % ",".join(
+            [opt.strip() for opt in job.pop("perftest-btime-variants")]
+        )
+
+        yield job
+
+
+@transforms.add
+def setup_perftest_extra_options(config, jobs):
+    for job in jobs:
+        if job.get("perftest-extra-options") is None:
+            yield job
+            continue
+        job["run"]["command"] += " " + " ".join(job.pop("perftest-extra-options"))
+        yield job
+
+
+@transforms.add
+def pass_perftest_options(config, jobs):
+    for job in jobs:
+        env = job.setdefault("worker", {}).setdefault("env", {})
+        env["PERFTEST_OPTIONS"] = json.dumps(
+            config.params["try_task_config"].get("perftest-options")
+        )
+        yield job
+
+
+@transforms.add
+def setup_perftest_test_date(config, jobs):
+    for job in jobs:
+        if (
+            job.get("attributes", {}).get("batch", False)
+            and "--test-date" not in job["run"]["command"]
+        ):
+            yesterday = (date.today() - timedelta(1)).strftime("%Y.%m.%d")
+            job["run"]["command"] += " --test-date %s" % yesterday
+        yield job
+
+
+@transforms.add
+def setup_regression_detector(config, jobs):
+    for job in jobs:
+        if "change-detector" in job.get("name"):
+
+            tasks_to_analyze = []
+            for task in config.params["try_task_config"].get("tasks", []):
+                # Explicitly skip these tasks since they're
+                # part of the mozperftest tasks
+                if "side-by-side" in task:
+                    continue
+                if "change-detector" in task:
+                    continue
+
+                # Select these tasks
+                if "browsertime" in task:
+                    tasks_to_analyze.append(task)
+                elif "talos" in task:
+                    tasks_to_analyze.append(task)
+                elif "awsy" in task:
+                    tasks_to_analyze.append(task)
+                elif "perftest" in task:
+                    tasks_to_analyze.append(task)
+
+            if len(tasks_to_analyze) == 0:
+                yield job
+                continue
+
+            # Make the change detector task depend on the tasks to analyze.
+            # This prevents the task from running until all data is available
+            # within the current push.
+            job["soft-dependencies"] = tasks_to_analyze
+            job["requires"] = "all-completed"
+
+            new_project = config.params["project"]
+            if (
+                "try" in config.params["project"]
+                or config.params["try_mode"] == "try_select"
+            ):
+                new_project = "try"
+
+            base_project = None
+            if (
+                config.params.get("try_task_config", {})
+                .get("env", {})
+                .get("PERF_BASE_REVISION", None)
+                is not None
+            ):
+                task_names = " --task-name ".join(tasks_to_analyze)
+                base_revision = config.params["try_task_config"]["env"][
+                    "PERF_BASE_REVISION"
+                ]
+                base_project = new_project
+
+                # Add all the required information to the task
+                job["run"]["command"] = job["run"]["command"].format(
+                    task_name=task_names,
+                    base_revision=base_revision,
+                    base_branch=base_project,
+                    new_branch=new_project,
+                    new_revision=config.params["head_rev"],
+                )
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/python_update.py b/taskcluster/gecko_taskgraph/transforms/python_update.py
new file mode 100644
index 0000000000..f4f135b585
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/python_update.py
@@ -0,0 +1,25 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repo-update task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def resolve_keys(config, tasks):
+    for task in tasks:
+        env = task["worker"].setdefault("env", {})
+        env["BRANCH"] = config.params["project"]
+        for envvar in env:
+            resolve_keyed_by(env, envvar, envvar, **config.params)
+
+        for envvar in list(env.keys()):
+            if not env.get(envvar):
+                del env[envvar]
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/release.py b/taskcluster/gecko_taskgraph/transforms/release.py
new file mode 100644
index 0000000000..1158252fe7
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release.py
@@ -0,0 +1,20 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Transforms for release tasks
+"""
+
+
+def run_on_releases(config, jobs):
+    """
+    Filter out jobs with `run-on-releases` set, and that don't match the
+    `release_type` paramater.
+    """
+    for job in jobs:
+        release_type = config.params["release_type"]
+        run_on_release_types = job.pop("run-on-releases", None)
+
+        if run_on_release_types is None or release_type in run_on_release_types:
+            yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_beetmover_signed_addons.py b/taskcluster/gecko_taskgraph/transforms/release_beetmover_signed_addons.py
new file mode 100644
index 0000000000..fb8eb91f44
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_beetmover_signed_addons.py
@@ -0,0 +1,243 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+import copy
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import inherit_treeherder_from_dep
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+logger = logging.getLogger(__name__)
+
+
+transforms = TransformSequence()
+
+
+beetmover_description_schema = schema.extend(
+    {
+        # attributes is used for enabling artifact-map by declarative artifacts
+        Required("attributes"): {str: object},
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Optional("label"): str,
+        # treeherder is allowed here to override any defaults we use for beetmover.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Required("description"): str,
+        Required("worker-type"): optionally_keyed_by("release-level", str),
+        Required("run-on-projects"): [],
+        # locale is passed only for l10n beetmoving
+        Optional("locale"): str,
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+
+transforms.add_validate(beetmover_description_schema)
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        for field in ("worker-type", "attributes.artifact_map"):
+            resolve_keyed_by(
+                job,
+                field,
+                item_name=job["label"],
+                **{
+                    "release-level": release_level(config.params["project"]),
+                    "release-type": config.params["release_type"],
+                    "project": config.params["project"],
+                },
+            )
+        yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault(
+            "symbol", "langpack(BM{})".format(attributes.get("l10n_chunk", ""))
+        )
+
+        job["attributes"].update(copy_attributes_from_dependent_job(dep_job))
+        job["attributes"]["chunk_locales"] = dep_job.attributes.get(
+            "chunk_locales", ["en-US"]
+        )
+
+        job["description"] = job["description"].format(
+            locales="/".join(job["attributes"]["chunk_locales"]),
+            platform=job["attributes"]["build_platform"],
+        )
+
+        job["scopes"] = [
+            get_beetmover_bucket_scope(config),
+            get_beetmover_action_scope(config),
+        ]
+
+        job["dependencies"] = {"langpack-copy": dep_job.label}
+
+        job["run-on-projects"] = job.get(
+            "run_on_projects", dep_job.attributes["run_on_projects"]
+        )
+        job["treeherder"] = treeherder
+        job["shipping-phase"] = job.get(
+            "shipping-phase", dep_job.attributes["shipping_phase"]
+        )
+        job["shipping-product"] = dep_job.attributes["shipping_product"]
+
+        yield job
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        platform = job["attributes"]["build_platform"]
+        locale = job["attributes"]["chunk_locales"]
+
+        job["worker"] = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config,
+                job,
+                platform,
+                locale,
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform, locale=locale
+            ),
+        }
+
+        yield job
+
+
+@transforms.add
+def strip_unused_data(config, jobs):
+    for job in jobs:
+        del job["primary-dependency"]
+
+        yield job
+
+
+@transforms.add
+def yield_all_platform_jobs(config, jobs):
+    # Even though langpacks are now platform independent, we keep beetmoving them at old
+    # platform-specific locations. That's why this transform exist
+    # The linux64 and mac specific ja-JP-mac are beetmoved along with the signing beetmover
+    # So while the dependent jobs are linux here, we only yield jobs for other platforms
+    for job in jobs:
+        platforms = ("linux", "macosx64", "win32", "win64")
+        if "devedition" in job["attributes"]["build_platform"]:
+            platforms = (f"{plat}-devedition" for plat in platforms)
+        for platform in platforms:
+            platform_job = copy.deepcopy(job)
+            if "ja" in platform_job["attributes"]["chunk_locales"] and platform in (
+                "macosx64",
+                "macosx64-devedition",
+            ):
+                platform_job = _strip_ja_data_from_linux_job(platform_job)
+
+            platform_job = _change_platform_data(config, platform_job, platform)
+
+            yield platform_job
+
+
+def _strip_ja_data_from_linux_job(platform_job):
+    # Let's take "ja" out the description. This locale is in a substring like "aa/bb/cc/dd", where
+    # "ja" could be any of "aa", "bb", "cc", "dd"
+    platform_job["description"] = platform_job["description"].replace("ja/", "")
+    platform_job["description"] = platform_job["description"].replace("/ja", "")
+
+    platform_job["worker"]["upstream-artifacts"] = [
+        artifact
+        for artifact in platform_job["worker"]["upstream-artifacts"]
+        if artifact["locale"] != "ja"
+    ]
+
+    return platform_job
+
+
+def _change_platform_in_artifact_map_paths(paths, orig_platform, new_platform):
+    amended_paths = {}
+    for artifact, artifact_info in paths.items():
+        amended_artifact_info = {
+            "checksums_path": artifact_info["checksums_path"].replace(
+                orig_platform, new_platform
+            ),
+            "destinations": [
+                d.replace(orig_platform, new_platform)
+                for d in artifact_info["destinations"]
+            ],
+        }
+        amended_paths[artifact] = amended_artifact_info
+
+    return amended_paths
+
+
+def _change_platform_data(config, platform_job, platform):
+    orig_platform = "linux64"
+    if "devedition" in platform:
+        orig_platform = "linux64-devedition"
+    platform_job["attributes"]["build_platform"] = platform
+    platform_job["label"] = platform_job["label"].replace(orig_platform, platform)
+    platform_job["description"] = platform_job["description"].replace(
+        orig_platform, platform
+    )
+    platform_job["treeherder"]["platform"] = platform_job["treeherder"][
+        "platform"
+    ].replace(orig_platform, platform)
+    platform_job["worker"]["release-properties"]["platform"] = platform
+
+    # amend artifactMap entries as well
+    platform_mapping = {
+        "linux64": "linux-x86_64",
+        "linux": "linux-i686",
+        "macosx64": "mac",
+        "win32": "win32",
+        "win64": "win64",
+        "linux64-devedition": "linux-x86_64",
+        "linux-devedition": "linux-i686",
+        "macosx64-devedition": "mac",
+        "win32-devedition": "win32",
+        "win64-devedition": "win64",
+    }
+    orig_platform = platform_mapping.get(orig_platform, orig_platform)
+    platform = platform_mapping.get(platform, platform)
+    platform_job["worker"]["artifact-map"] = [
+        {
+            "locale": entry["locale"],
+            "taskId": entry["taskId"],
+            "paths": _change_platform_in_artifact_map_paths(
+                entry["paths"], orig_platform, platform
+            ),
+        }
+        for entry in platform_job["worker"]["artifact-map"]
+    ]
+
+    return platform_job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_deps.py b/taskcluster/gecko_taskgraph/transforms/release_deps.py
new file mode 100644
index 0000000000..e44af576eb
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_deps.py
@@ -0,0 +1,61 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add dependencies to release tasks.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+PHASES = ["build", "promote", "push", "ship"]
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_dependencies(config, jobs):
+    for job in jobs:
+        dependencies = {}
+        # Add any kind_dependencies_tasks with matching product as dependencies
+        product = job.get("shipping-product")
+        phase = job.get("shipping-phase")
+        if product is None:
+            continue
+
+        required_signoffs = set(
+            job.setdefault("attributes", {}).get("required_signoffs", [])
+        )
+        for dep_task in config.kind_dependencies_tasks.values():
+            # Weed out unwanted tasks.
+            # XXX we have run-on-projects which specifies the on-push behavior;
+            # we need another attribute that specifies release promotion,
+            # possibly which action(s) each task belongs in.
+
+            # We can only depend on tasks in the current or previous phases
+            dep_phase = dep_task.attributes.get("shipping_phase")
+            if dep_phase and PHASES.index(dep_phase) > PHASES.index(phase):
+                continue
+
+            if dep_task.attributes.get("build_platform") and job.get(
+                "attributes", {}
+            ).get("build_platform"):
+                if (
+                    dep_task.attributes["build_platform"]
+                    != job["attributes"]["build_platform"]
+                ):
+                    continue
+            # Add matching product tasks to deps
+            if (
+                dep_task.task.get("shipping-product") == product
+                or dep_task.attributes.get("shipping_product") == product
+            ):
+                dependencies[dep_task.label] = dep_task.label
+                required_signoffs.update(
+                    dep_task.attributes.get("required_signoffs", [])
+                )
+
+        job.setdefault("dependencies", {}).update(dependencies)
+        if required_signoffs:
+            job["attributes"]["required_signoffs"] = sorted(required_signoffs)
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_flatpak_push.py b/taskcluster/gecko_taskgraph/transforms/release_flatpak_push.py
new file mode 100644
index 0000000000..8a336502e6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_flatpak_push.py
@@ -0,0 +1,79 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the release-flatpak-push kind into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import add_scope_prefix
+
+push_flatpak_description_schema = Schema(
+    {
+        Required("name"): str,
+        Required("job-from"): task_description_schema["job-from"],
+        Required("dependencies"): task_description_schema["dependencies"],
+        Required("description"): task_description_schema["description"],
+        Required("treeherder"): task_description_schema["treeherder"],
+        Required("run-on-projects"): task_description_schema["run-on-projects"],
+        Required("worker-type"): optionally_keyed_by("release-level", str),
+        Required("worker"): object,
+        Optional("scopes"): [str],
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Required("shipping-product"): task_description_schema["shipping-product"],
+        Optional("extra"): task_description_schema["extra"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(push_flatpak_description_schema)
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        if len(job["dependencies"]) != 1:
+            raise Exception("Exactly 1 dependency is required")
+
+        job["worker"]["upstream-artifacts"] = generate_upstream_artifacts(
+            job["dependencies"]
+        )
+
+        resolve_keyed_by(
+            job,
+            "worker.channel",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]},
+        )
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        if release_level(config.params["project"]) == "production":
+            job.setdefault("scopes", []).append(
+                add_scope_prefix(
+                    config,
+                    "flathub:firefox:{}".format(job["worker"]["channel"]),
+                )
+            )
+
+        yield job
+
+
+def generate_upstream_artifacts(dependencies):
+    return [
+        {
+            "taskId": {"task-reference": f"<{task_kind}>"},
+            "taskType": "build",
+            "paths": ["public/build/target.flatpak.tar.xz"],
+        }
+        for task_kind in dependencies.keys()
+    ]
diff --git a/taskcluster/gecko_taskgraph/transforms/release_flatpak_repackage.py b/taskcluster/gecko_taskgraph/transforms/release_flatpak_repackage.py
new file mode 100644
index 0000000000..7af1134c3a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_flatpak_repackage.py
@@ -0,0 +1,42 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def format(config, tasks):
+    """Apply format substitution to worker.env and worker.command."""
+
+    format_params = {
+        "release_config": get_release_config(config),
+        "config_params": config.params,
+    }
+
+    for task in tasks:
+        format_params["task"] = task
+
+        command = task.get("worker", {}).get("command", [])
+        task["worker"]["command"] = [x.format(**format_params) for x in command]
+
+        env = task.get("worker", {}).get("env", {})
+        for k in env.keys():
+            resolve_keyed_by(
+                env,
+                k,
+                "flatpak envs",
+                **{
+                    "release-level": release_level(config.params["project"]),
+                    "project": config.params["project"],
+                }
+            )
+            task["worker"]["env"][k] = env[k].format(**format_params)
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/release_generate_checksums.py b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums.py
new file mode 100644
index 0000000000..0024b88726
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums.py
@@ -0,0 +1,53 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the checksums task into an actual task description.
+"""
+
+import copy
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by project, etc."""
+    fields = [
+        "run.config",
+        "run.extra-config",
+    ]
+    for job in jobs:
+        job = copy.deepcopy(job)
+        for field in fields:
+            resolve_keyed_by(
+                item=job,
+                field=field,
+                item_name=job["name"],
+                **{"release-level": release_level(config.params["project"])}
+            )
+        yield job
+
+
+@transforms.add
+def interpolate(config, jobs):
+    release_config = get_release_config(config)
+    for job in jobs:
+        mh_options = list(job["run"]["options"])
+        job["run"]["options"] = [
+            option.format(
+                version=release_config["version"],
+                build_number=release_config["build_number"],
+            )
+            for option in mh_options
+        ]
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_beetmover.py b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_beetmover.py
new file mode 100644
index 0000000000..c91e807b27
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_beetmover.py
@@ -0,0 +1,118 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the `release-generate-checksums-beetmover` task to also append `build` as dependency
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.beetmover import craft_release_properties
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+    get_beetmover_action_scope,
+    get_beetmover_bucket_scope,
+)
+
+transforms = TransformSequence()
+
+
+release_generate_checksums_beetmover_schema = schema.extend(
+    {
+        # unique label to describe this beetmover task, defaults to {dep.label}-beetmover
+        Optional("label"): str,
+        # treeherder is allowed here to override any defaults we use for beetmover.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(release_generate_checksums_beetmover_schema)
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes.update(job.get("attributes", {}))
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "BM-SGenChcks")
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+
+        job_template = f"{dep_job.label}"
+        label = job_template.replace("signing", "beetmover")
+
+        description = "Transfer *SUMS and *SUMMARY checksums file to S3."
+
+        # first dependency is the signing task for the *SUMS files
+        dependencies = {dep_job.kind: dep_job.label}
+
+        if len(dep_job.dependencies) > 1:
+            raise NotImplementedError(
+                "Can't beetmove a signing task with multiple dependencies"
+            )
+        # update the dependencies with the dependencies of the signing task
+        dependencies.update(dep_job.dependencies)
+
+        bucket_scope = get_beetmover_bucket_scope(config)
+        action_scope = get_beetmover_action_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "beetmover",
+            "scopes": [bucket_scope, action_scope],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+            "shipping-phase": "promote",
+        }
+
+        yield task
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        valid_beetmover_job = len(job["dependencies"]) == 2 and any(
+            ["signing" in j for j in job["dependencies"]]
+        )
+        if not valid_beetmover_job:
+            raise NotImplementedError("Beetmover must have two dependencies.")
+
+        platform = job["attributes"]["build_platform"]
+        worker = {
+            "implementation": "beetmover",
+            "release-properties": craft_release_properties(config, job),
+            "upstream-artifacts": generate_beetmover_upstream_artifacts(
+                config, job, platform=None, locale=None
+            ),
+            "artifact-map": generate_beetmover_artifact_map(
+                config, job, platform=platform
+            ),
+        }
+
+        job["worker"] = worker
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_signing.py b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_signing.py
new file mode 100644
index 0000000000..6dfee1d33b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_generate_checksums_signing.py
@@ -0,0 +1,86 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the release-generate-checksums-signing task into task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_path
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope
+
+release_generate_checksums_signing_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(release_generate_checksums_signing_schema)
+
+
+@transforms.add
+def make_release_generate_checksums_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "SGenChcks")
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+
+        job_template = "{}-{}".format(dep_job.label, "signing")
+        label = job.get("label", job_template)
+        description = "Signing of the overall release-related checksums"
+
+        dependencies = {dep_job.kind: dep_job.label}
+
+        upstream_artifacts = [
+            {
+                "taskId": {"task-reference": f"<{str(dep_job.kind)}>"},
+                "taskType": "build",
+                "paths": [
+                    get_artifact_path(dep_job, "SHA256SUMS"),
+                    get_artifact_path(dep_job, "SHA512SUMS"),
+                ],
+                "formats": ["autograph_gpg"],
+            }
+        ]
+
+        signing_cert_scope = get_signing_cert_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "linux-signing",
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+                "max-run-time": 3600,
+            },
+            "scopes": [
+                signing_cert_scope,
+            ],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+        }
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/release_mark_as_shipped.py b/taskcluster/gecko_taskgraph/transforms/release_mark_as_shipped.py
new file mode 100644
index 0000000000..f2ce148320
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_mark_as_shipped.py
@@ -0,0 +1,39 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    release_config = get_release_config(config)
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+        resolve_keyed_by(
+            job,
+            "scopes",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])}
+        )
+
+        job["worker"][
+            "release-name"
+        ] = "{product}-{version}-build{build_number}".format(
+            product=job["shipping-product"].capitalize(),
+            version=release_config["version"],
+            build_number=release_config["build_number"],
+        )
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_msix_push.py b/taskcluster/gecko_taskgraph/transforms/release_msix_push.py
new file mode 100644
index 0000000000..817341f92c
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_msix_push.py
@@ -0,0 +1,88 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the release-msix-push kind into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import add_scope_prefix
+
+push_msix_description_schema = Schema(
+    {
+        Required("name"): str,
+        Required("job-from"): task_description_schema["job-from"],
+        Required("dependencies"): task_description_schema["dependencies"],
+        Required("description"): task_description_schema["description"],
+        Required("treeherder"): task_description_schema["treeherder"],
+        Required("run-on-projects"): task_description_schema["run-on-projects"],
+        Required("worker-type"): optionally_keyed_by("release-level", str),
+        Required("worker"): object,
+        Optional("scopes"): [str],
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Required("shipping-product"): task_description_schema["shipping-product"],
+        Optional("extra"): task_description_schema["extra"],
+        Optional("attributes"): task_description_schema["attributes"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(push_msix_description_schema)
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+
+        job["worker"]["upstream-artifacts"] = generate_upstream_artifacts(
+            job["dependencies"]
+        )
+
+        resolve_keyed_by(
+            job,
+            "worker.channel",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]},
+        )
+        resolve_keyed_by(
+            job,
+            "worker.publish-mode",
+            item_name=job["name"],
+            **{"release-type": config.params["release_type"]},
+        )
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["name"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        if release_level(config.params["project"]) == "production":
+            job.setdefault("scopes", []).append(
+                add_scope_prefix(
+                    config,
+                    "microsoftstore:{}".format(job["worker"]["channel"]),
+                )
+            )
+
+        # Override shipping-phase for release: push to the Store early to
+        # allow time for certification.
+        if job["worker"]["publish-mode"] == "Manual":
+            job["shipping-phase"] = "promote"
+
+        yield job
+
+
+def generate_upstream_artifacts(dependencies):
+    return [
+        {
+            "taskId": {"task-reference": f"<{task_kind}>"},
+            "taskType": "build",
+            "paths": ["public/build/target.store.msix"],
+        }
+        for task_kind in dependencies.keys()
+    ]
diff --git a/taskcluster/gecko_taskgraph/transforms/release_notifications.py b/taskcluster/gecko_taskgraph/transforms/release_notifications.py
new file mode 100644
index 0000000000..86109ec5ed
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_notifications.py
@@ -0,0 +1,73 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add notifications via taskcluster-notify for release tasks
+"""
+from string import Formatter
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+class TitleCaseFormatter(Formatter):
+    """Support title formatter for strings"""
+
+    def convert_field(self, value, conversion):
+        if conversion == "t":
+            return str(value).title()
+        super().convert_field(value, conversion)
+        return value
+
+
+titleformatter = TitleCaseFormatter()
+
+
+@transforms.add
+def add_notifications(config, jobs):
+    release_config = get_release_config(config)
+
+    for job in jobs:
+        label = "{}-{}".format(config.kind, job["name"])
+
+        notifications = job.pop("notifications", None)
+        if notifications:
+            resolve_keyed_by(
+                notifications, "emails", label, project=config.params["project"]
+            )
+            emails = notifications["emails"]
+            format_kwargs = dict(
+                task=job,
+                config=config.__dict__,
+                release_config=release_config,
+            )
+            subject = titleformatter.format(notifications["subject"], **format_kwargs)
+            message = titleformatter.format(notifications["message"], **format_kwargs)
+            emails = [email.format(**format_kwargs) for email in emails]
+
+            # By default, we only send mail on success to avoid messages like 'blah is in the
+            # candidates dir' when cancelling graphs, dummy job failure, etc
+            status_types = notifications.get("status-types", ["on-completed"])
+            for s in status_types:
+                job.setdefault("routes", []).extend(
+                    [f"notify.email.{email}.{s}" for email in emails]
+                )
+
+            # Customize the email subject to include release name and build number
+            job.setdefault("extra", {}).update(
+                {
+                    "notify": {
+                        "email": {
+                            "subject": subject,
+                        }
+                    }
+                }
+            )
+            if message:
+                job["extra"]["notify"]["email"]["content"] = message
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_sign_and_push_langpacks.py b/taskcluster/gecko_taskgraph/transforms/release_sign_and_push_langpacks.py
new file mode 100644
index 0000000000..17e4d37fb3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_sign_and_push_langpacks.py
@@ -0,0 +1,180 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the release-sign-and-push task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import inherit_treeherder_from_dep
+from voluptuous import Any, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+
+transforms = TransformSequence()
+
+langpack_sign_push_description_schema = schema.extend(
+    {
+        Required("label"): str,
+        Required("description"): str,
+        Required("worker-type"): optionally_keyed_by("release-level", str),
+        Required("worker"): {
+            Required("channel"): optionally_keyed_by(
+                "project", "platform", Any("listed", "unlisted")
+            ),
+            Required("upstream-artifacts"): None,  # Processed here below
+        },
+        Required("run-on-projects"): [],
+        Required("scopes"): optionally_keyed_by("release-level", [str]),
+        Required("shipping-phase"): task_description_schema["shipping-phase"],
+        Required("shipping-product"): task_description_schema["shipping-product"],
+    }
+)
+
+
+@transforms.add
+def set_label(config, jobs):
+    for job in jobs:
+        label = "push-langpacks-{}".format(job["primary-dependency"].label)
+        job["label"] = label
+
+        yield job
+
+
+transforms.add_validate(langpack_sign_push_description_schema)
+
+
+@transforms.add
+def resolve_keys(config, jobs):
+    for job in jobs:
+        resolve_keyed_by(
+            job,
+            "worker-type",
+            item_name=job["label"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        resolve_keyed_by(
+            job,
+            "scopes",
+            item_name=job["label"],
+            **{"release-level": release_level(config.params["project"])},
+        )
+        resolve_keyed_by(
+            job,
+            "worker.channel",
+            item_name=job["label"],
+            project=config.params["project"],
+            platform=job["primary-dependency"].attributes["build_platform"],
+        )
+
+        yield job
+
+
+@transforms.add
+def copy_attributes(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        job["attributes"] = copy_attributes_from_dependent_job(dep_job)
+        job["attributes"]["chunk_locales"] = dep_job.attributes.get(
+            "chunk_locales", ["en-US"]
+        )
+
+        yield job
+
+
+@transforms.add
+def filter_out_macos_jobs_but_mac_only_locales(config, jobs):
+    for job in jobs:
+        build_platform = job["primary-dependency"].attributes.get("build_platform")
+
+        if build_platform in ("linux64-devedition", "linux64-shippable"):
+            yield job
+        elif (
+            build_platform in ("macosx64-devedition", "macosx64-shippable")
+            and "ja-JP-mac" in job["attributes"]["chunk_locales"]
+        ):
+            # Other locales of the same job shouldn't be processed
+            job["attributes"]["chunk_locales"] = ["ja-JP-mac"]
+            job["label"] = job["label"].replace(
+                # Guard against a chunk 10 or chunk 1 (latter on try) weird munging
+                "-{}/".format(job["attributes"]["l10n_chunk"]),
+                "-ja-JP-mac/",
+            )
+            yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        treeherder = inherit_treeherder_from_dep(job, dep_job)
+        treeherder.setdefault(
+            "symbol", "langpack(SnP{})".format(job["attributes"].get("l10n_chunk", ""))
+        )
+
+        job["description"] = job["description"].format(
+            locales="/".join(job["attributes"]["chunk_locales"]),
+        )
+
+        job["dependencies"] = {dep_job.kind: dep_job.label}
+        job["treeherder"] = treeherder
+
+        yield job
+
+
+def generate_upstream_artifacts(upstream_task_ref, locales):
+    return [
+        {
+            "taskId": {"task-reference": upstream_task_ref},
+            "taskType": "build",
+            "paths": [
+                "public/build{locale}/target.langpack.xpi".format(
+                    locale="" if locale == "en-US" else "/" + locale
+                )
+                for locale in locales
+            ],
+        }
+    ]
+
+
+@transforms.add
+def make_task_worker(config, jobs):
+    for job in jobs:
+        upstream_task_ref = get_upstream_task_ref(
+            job, expected_kinds=("build", "shippable-l10n")
+        )
+
+        job["worker"]["implementation"] = "push-addons"
+        job["worker"]["upstream-artifacts"] = generate_upstream_artifacts(
+            upstream_task_ref, job["attributes"]["chunk_locales"]
+        )
+
+        yield job
+
+
+def get_upstream_task_ref(job, expected_kinds):
+    upstream_tasks = [
+        job_kind
+        for job_kind in job["dependencies"].keys()
+        if job_kind in expected_kinds
+    ]
+
+    if len(upstream_tasks) > 1:
+        raise Exception("Only one dependency expected")
+
+    return f"<{upstream_tasks[0]}>"
+
+
+@transforms.add
+def strip_unused_data(config, jobs):
+    for job in jobs:
+        del job["primary-dependency"]
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_snap_repackage.py b/taskcluster/gecko_taskgraph/transforms/release_snap_repackage.py
new file mode 100644
index 0000000000..659a203971
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_snap_repackage.py
@@ -0,0 +1,39 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def format(config, tasks):
+    """Apply format substitution to worker.env and worker.command."""
+
+    format_params = {
+        "release_config": get_release_config(config),
+        "config_params": config.params,
+    }
+
+    for task in tasks:
+        format_params["task"] = task
+
+        command = task.get("worker", {}).get("command", [])
+        task["worker"]["command"] = [x.format(**format_params) for x in command]
+
+        env = task.get("worker", {}).get("env", {})
+        for k in env.keys():
+            resolve_keyed_by(
+                env,
+                k,
+                "snap envs",
+                **{"release-level": release_level(config.params["project"])}
+            )
+            task["worker"]["env"][k] = env[k].format(**format_params)
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/release_started.py b/taskcluster/gecko_taskgraph/transforms/release_started.py
new file mode 100644
index 0000000000..0f54c8e098
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_started.py
@@ -0,0 +1,52 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add notifications via taskcluster-notify for release tasks
+"""
+from pipes import quote as shell_quote
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_notifications(config, jobs):
+    for job in jobs:
+        label = "{}-{}".format(config.kind, job["name"])
+
+        resolve_keyed_by(job, "emails", label, project=config.params["project"])
+        emails = [email.format(config=config.__dict__) for email in job.pop("emails")]
+
+        command = [
+            "release",
+            "send-buglist-email",
+            "--version",
+            config.params["version"],
+            "--product",
+            job["shipping-product"],
+            "--revision",
+            config.params["head_rev"],
+            "--build-number",
+            str(config.params["build_number"]),
+            "--repo",
+            config.params["head_repository"],
+        ]
+        for address in emails:
+            command += ["--address", address]
+        command += [
+            # We wrap this in `{'task-reference': ...}` below
+            "--task-group-id",
+            "<decision>",
+        ]
+
+        job["scopes"] = [f"notify:email:{address}" for address in emails]
+        job["run"] = {
+            "using": "mach",
+            "sparse-profile": "mach",
+            "mach": {"task-reference": " ".join(map(shell_quote, command))},
+        }
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/release_version_bump.py b/taskcluster/gecko_taskgraph/transforms/release_version_bump.py
new file mode 100644
index 0000000000..a0f3f69d05
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/release_version_bump.py
@@ -0,0 +1,42 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the update generation task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def handle_keyed_by(config, tasks):
+    """Resolve fields that can be keyed by platform, etc."""
+    default_fields = [
+        "worker.push",
+        "worker.bump-files",
+        "worker-type",
+    ]
+    for task in tasks:
+        fields = default_fields[:]
+        for additional_field in (
+            "l10n-bump-info",
+            "source-repo",
+            "dontbuild",
+            "ignore-closed-tree",
+        ):
+            if additional_field in task["worker"]:
+                fields.append(f"worker.{additional_field}")
+        for field in fields:
+            resolve_keyed_by(
+                task,
+                field,
+                item_name=task["name"],
+                **{
+                    "project": config.params["project"],
+                    "release-type": config.params["release_type"],
+                },
+            )
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage.py b/taskcluster/gecko_taskgraph/transforms/repackage.py
new file mode 100644
index 0000000000..2fe849c32d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage.py
@@ -0,0 +1,684 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+from voluptuous import Extra, Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.job import job_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.copy_task import copy_task
+from gecko_taskgraph.util.platforms import architecture, archive_format
+from gecko_taskgraph.util.workertypes import worker_type_implementation
+
+packaging_description_schema = schema.extend(
+    {
+        # unique label to describe this repackaging task
+        Optional("label"): str,
+        Optional("worker-type"): str,
+        Optional("worker"): object,
+        # treeherder is allowed here to override any defaults we use for repackaging.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): job_description_schema["treeherder"],
+        # If a l10n task, the corresponding locale
+        Optional("locale"): str,
+        # Routes specific to this task, if defined
+        Optional("routes"): [str],
+        # passed through directly to the job description
+        Optional("extra"): job_description_schema["extra"],
+        # passed through to job description
+        Optional("fetches"): job_description_schema["fetches"],
+        Optional("run-on-projects"): job_description_schema["run-on-projects"],
+        # Shipping product and phase
+        Optional("shipping-product"): job_description_schema["shipping-product"],
+        Optional("shipping-phase"): job_description_schema["shipping-phase"],
+        Required("package-formats"): optionally_keyed_by(
+            "build-platform", "release-type", [str]
+        ),
+        Optional("msix"): {
+            Optional("channel"): optionally_keyed_by(
+                "package-format",
+                "level",
+                "build-platform",
+                "release-type",
+                "shipping-product",
+                str,
+            ),
+            Optional("identity-name"): optionally_keyed_by(
+                "package-format",
+                "level",
+                "build-platform",
+                "release-type",
+                "shipping-product",
+                str,
+            ),
+            Optional("publisher"): optionally_keyed_by(
+                "package-format",
+                "level",
+                "build-platform",
+                "release-type",
+                "shipping-product",
+                str,
+            ),
+            Optional("publisher-display-name"): optionally_keyed_by(
+                "package-format",
+                "level",
+                "build-platform",
+                "release-type",
+                "shipping-product",
+                str,
+            ),
+            Optional("vendor"): str,
+        },
+        # All l10n jobs use mozharness
+        Required("mozharness"): {
+            Extra: object,
+            # Config files passed to the mozharness script
+            Required("config"): optionally_keyed_by("build-platform", [str]),
+            # Additional paths to look for mozharness configs in. These should be
+            # relative to the base of the source checkout
+            Optional("config-paths"): [str],
+            # if true, perform a checkout of a comm-central based branch inside the
+            # gecko checkout
+            Optional("comm-checkout"): bool,
+            Optional("run-as-root"): bool,
+            Optional("use-caches"): bool,
+        },
+    }
+)
+
+# The configuration passed to the mozharness repackage script. This defines the
+# arguments passed to `mach repackage`
+# - `args` is interpolated by mozharness (`{package-name}`, `{installer-tag}`,
+#   `{stub-installer-tag}`, `{sfx-stub}`, `{wsx-stub}`, `{fetch-dir}`), with values
+#    from mozharness.
+# - `inputs` are passed as long-options, with the filename prefixed by
+#   `MOZ_FETCH_DIR`. The filename is interpolated by taskgraph
+#   (`{archive_format}`).
+# - `output` is passed to `--output`, with the filename prefixed by the output
+#   directory.
+PACKAGE_FORMATS = {
+    "mar": {
+        "args": [
+            "mar",
+            "--arch",
+            "{architecture}",
+            "--mar-channel-id",
+            "{mar-channel-id}",
+        ],
+        "inputs": {
+            "input": "target{archive_format}",
+            "mar": "mar-tools/mar",
+        },
+        "output": "target.complete.mar",
+    },
+    "msi": {
+        "args": [
+            "msi",
+            "--wsx",
+            "{wsx-stub}",
+            "--version",
+            "{version_display}",
+            "--locale",
+            "{_locale}",
+            "--arch",
+            "{architecture}",
+            "--candle",
+            "{fetch-dir}/candle.exe",
+            "--light",
+            "{fetch-dir}/light.exe",
+        ],
+        "inputs": {
+            "setupexe": "target.installer.exe",
+        },
+        "output": "target.installer.msi",
+    },
+    "msix": {
+        "args": [
+            "msix",
+            "--channel",
+            "{msix-channel}",
+            "--publisher",
+            "{msix-publisher}",
+            "--publisher-display-name",
+            "{msix-publisher-display-name}",
+            "--identity-name",
+            "{msix-identity-name}",
+            "--vendor",
+            "{msix-vendor}",
+            "--arch",
+            "{architecture}",
+            # For langpacks.  Ignored if directory does not exist.
+            "--distribution-dir",
+            "{fetch-dir}/distribution",
+            "--verbose",
+            "--makeappx",
+            "{fetch-dir}/msix-packaging/makemsix",
+        ],
+        "inputs": {
+            "input": "target{archive_format}",
+        },
+        "output": "target.installer.msix",
+    },
+    "msix-store": {
+        "args": [
+            "msix",
+            "--channel",
+            "{msix-channel}",
+            "--publisher",
+            "{msix-publisher}",
+            "--publisher-display-name",
+            "{msix-publisher-display-name}",
+            "--identity-name",
+            "{msix-identity-name}",
+            "--vendor",
+            "{msix-vendor}",
+            "--arch",
+            "{architecture}",
+            # For langpacks.  Ignored if directory does not exist.
+            "--distribution-dir",
+            "{fetch-dir}/distribution",
+            "--verbose",
+            "--makeappx",
+            "{fetch-dir}/msix-packaging/makemsix",
+        ],
+        "inputs": {
+            "input": "target{archive_format}",
+        },
+        "output": "target.store.msix",
+    },
+    "dmg": {
+        "args": ["dmg"],
+        "inputs": {
+            "input": "target{archive_format}",
+        },
+        "output": "target.dmg",
+    },
+    "pkg": {
+        "args": ["pkg"],
+        "inputs": {
+            "input": "target{archive_format}",
+        },
+        "output": "target.pkg",
+    },
+    "installer": {
+        "args": [
+            "installer",
+            "--package-name",
+            "{package-name}",
+            "--tag",
+            "{installer-tag}",
+            "--sfx-stub",
+            "{sfx-stub}",
+        ],
+        "inputs": {
+            "package": "target{archive_format}",
+            "setupexe": "setup.exe",
+        },
+        "output": "target.installer.exe",
+    },
+    "installer-stub": {
+        "args": [
+            "installer",
+            "--tag",
+            "{stub-installer-tag}",
+            "--sfx-stub",
+            "{sfx-stub}",
+        ],
+        "inputs": {
+            "setupexe": "setup-stub.exe",
+        },
+        "output": "target.stub-installer.exe",
+    },
+    "deb": {
+        "args": [
+            "deb",
+            "--arch",
+            "{architecture}",
+            "--templates",
+            "browser/installer/linux/app/debian",
+            "--version",
+            "{version_display}",
+            "--build-number",
+            "{build_number}",
+            "--release-product",
+            "{release_product}",
+            "--release-type",
+            "{release_type}",
+        ],
+        "inputs": {
+            "input": "target{archive_format}",
+        },
+        "output": "target.deb",
+    },
+    "deb-l10n": {
+        "args": [
+            "deb-l10n",
+            "--version",
+            "{version_display}",
+            "--build-number",
+            "{build_number}",
+            "--templates",
+            "browser/installer/linux/langpack/debian",
+        ],
+        "inputs": {
+            "input-xpi-file": "target.langpack.xpi",
+            "input-tar-file": "target{archive_format}",
+        },
+        "output": "target.langpack.deb",
+    },
+}
+MOZHARNESS_EXPANSIONS = [
+    "package-name",
+    "installer-tag",
+    "fetch-dir",
+    "stub-installer-tag",
+    "sfx-stub",
+    "wsx-stub",
+]
+
+transforms = TransformSequence()
+transforms.add_validate(packaging_description_schema)
+
+
+@transforms.add
+def copy_in_useful_magic(config, jobs):
+    """Copy attributes from upstream task to be used for keyed configuration."""
+    for job in jobs:
+        dep = job["primary-dependency"]
+        job["build-platform"] = dep.attributes.get("build_platform")
+        job["shipping-product"] = dep.attributes.get("shipping_product")
+        yield job
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by platform, etc, but not `msix.*` fields
+    that can be keyed by `package-format`.  Such fields are handled specially below.
+    """
+    fields = [
+        "mozharness.config",
+        "package-formats",
+        "worker.max-run-time",
+    ]
+    for job in jobs:
+        job = copy_task(job)  # don't overwrite dict values here
+        for field in fields:
+            resolve_keyed_by(
+                item=job,
+                field=field,
+                item_name="?",
+                **{
+                    "release-type": config.params["release_type"],
+                    "level": config.params["level"],
+                },
+            )
+        yield job
+
+
+@transforms.add
+def make_repackage_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        label = job.get("label", dep_job.label.replace("signing-", "repackage-"))
+        job["label"] = label
+
+        yield job
+
+
+@transforms.add
+def make_job_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        dependencies = {dep_job.kind: dep_job.label}
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes["repackage_type"] = "repackage"
+
+        locale = attributes.get("locale", job.get("locale"))
+        if locale:
+            attributes["locale"] = locale
+
+        description = (
+            "Repackaging for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "Rpk")
+        dep_th_platform = dep_job.task.get("extra", {}).get("treeherder-platform")
+        treeherder.setdefault("platform", dep_th_platform)
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+
+        # Search dependencies before adding langpack dependencies.
+        signing_task = None
+        repackage_signing_task = None
+        for dependency in dependencies.keys():
+            if "repackage-signing" in dependency:
+                repackage_signing_task = dependency
+            elif "signing" in dependency or "notarization" in dependency:
+                signing_task = dependency
+
+        if config.kind == "repackage-msi":
+            treeherder["symbol"] = "MSI({})".format(locale or "N")
+
+        elif config.kind == "repackage-msix":
+            assert not locale
+
+            # Like "MSIXs(Bs)".
+            treeherder["symbol"] = "MSIX({})".format(
+                dep_job.task.get("extra", {}).get("treeherder", {}).get("symbol", "B")
+            )
+
+        elif config.kind == "repackage-shippable-l10n-msix":
+            assert not locale
+
+            if attributes.get("l10n_chunk") or attributes.get("chunk_locales"):
+                # We don't want to produce MSIXes for single-locale repack builds.
+                continue
+
+            description = (
+                "Repackaging with multiple locales for build '"
+                "{build_platform}/{build_type}'".format(
+                    build_platform=attributes.get("build_platform"),
+                    build_type=attributes.get("build_type"),
+                )
+            )
+
+            # Like "MSIXs(Bs-multi)".
+            treeherder["symbol"] = "MSIX({}-multi)".format(
+                dep_job.task.get("extra", {}).get("treeherder", {}).get("symbol", "B")
+            )
+
+            fetches = job.setdefault("fetches", {})
+
+            # The keys are unique, like `shippable-l10n-signing-linux64-shippable-1/opt`, so we
+            # can't ask for the tasks directly, we must filter for them.
+            for t in config.kind_dependencies_tasks.values():
+                if t.kind != "shippable-l10n-signing":
+                    continue
+                if t.attributes["build_platform"] != "linux64-shippable":
+                    continue
+                if t.attributes["build_type"] != "opt":
+                    continue
+
+                dependencies.update({t.label: t.label})
+
+                fetches.update(
+                    {
+                        t.label: [
+                            {
+                                "artifact": f"{loc}/target.langpack.xpi",
+                                "extract": False,
+                                # Otherwise we can't disambiguate locales!
+                                "dest": f"distribution/extensions/{loc}",
+                            }
+                            for loc in t.attributes["chunk_locales"]
+                        ]
+                    }
+                )
+
+        elif config.kind == "repackage-deb":
+            attributes["repackage_type"] = "repackage-deb"
+            description = (
+                "Repackaging the '{build_platform}/{build_type}' "
+                "{version} build into a '.deb' package"
+            ).format(
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+                version=config.params["version"],
+            )
+
+        _fetch_subst_locale = "en-US"
+        if locale:
+            _fetch_subst_locale = locale
+
+        worker_type = job["worker-type"]
+        build_platform = attributes["build_platform"]
+
+        use_stub = attributes.get("stub-installer")
+
+        repackage_config = []
+        package_formats = job.get("package-formats")
+        if use_stub and not repackage_signing_task and "msix" not in package_formats:
+            # if repackage_signing_task doesn't exists, generate the stub installer
+            package_formats += ["installer-stub"]
+        for format in package_formats:
+            command = copy_task(PACKAGE_FORMATS[format])
+            substs = {
+                "archive_format": archive_format(build_platform),
+                "_locale": _fetch_subst_locale,
+                "architecture": architecture(build_platform),
+                "version_display": config.params["version"],
+                "mar-channel-id": attributes["mar-channel-id"],
+                "build_number": config.params["build_number"],
+                "release_product": config.params["release_product"],
+                "release_type": config.params["release_type"],
+            }
+            # Allow us to replace `args` as well, but specifying things expanded in mozharness
+            # without breaking .format and without allowing unknown through.
+            substs.update({name: f"{{{name}}}" for name in MOZHARNESS_EXPANSIONS})
+
+            # We need to resolve `msix.*` values keyed by `package-format` for each format, not
+            # just once, so we update a temporary copy just for extracting these values.
+            temp_job = copy_task(job)
+            for msix_key in (
+                "channel",
+                "identity-name",
+                "publisher",
+                "publisher-display-name",
+                "vendor",
+            ):
+                resolve_keyed_by(
+                    item=temp_job,
+                    field=f"msix.{msix_key}",
+                    item_name="?",
+                    **{
+                        "package-format": format,
+                        "release-type": config.params["release_type"],
+                        "level": config.params["level"],
+                    },
+                )
+
+                # Turn `msix.channel` into `msix-channel`, etc.
+                value = temp_job.get("msix", {}).get(msix_key)
+                if value:
+                    substs.update(
+                        {f"msix-{msix_key}": value},
+                    )
+
+            command["inputs"] = {
+                name: filename.format(**substs)
+                for name, filename in command["inputs"].items()
+            }
+            command["args"] = [arg.format(**substs) for arg in command["args"]]
+            if "installer" in format and "aarch64" not in build_platform:
+                command["args"].append("--use-upx")
+
+            repackage_config.append(command)
+
+        run = job.get("mozharness", {})
+        run.update(
+            {
+                "using": "mozharness",
+                "script": "mozharness/scripts/repackage.py",
+                "job-script": "taskcluster/scripts/builder/repackage.sh",
+                "actions": ["setup", "repackage"],
+                "extra-config": {
+                    "repackage_config": repackage_config,
+                },
+                "run-as-root": run.get("run-as-root", False),
+                "use-caches": run.get("use-caches", True),
+            }
+        )
+
+        worker = job.get("worker", {})
+        worker.update(
+            {
+                "chain-of-trust": True,
+                # Don't add generic artifact directory.
+                "skip-artifacts": True,
+            }
+        )
+        worker.setdefault("max-run-time", 3600)
+
+        if locale:
+            # Make sure we specify the locale-specific upload dir
+            worker.setdefault("env", {})["LOCALE"] = locale
+
+        worker["artifacts"] = _generate_task_output_files(
+            dep_job,
+            worker_type_implementation(config.graph_config, config.params, worker_type),
+            repackage_config=repackage_config,
+            locale=locale,
+        )
+        attributes["release_artifacts"] = [
+            artifact["name"] for artifact in worker["artifacts"]
+        ]
+
+        task = {
+            "label": job["label"],
+            "description": description,
+            "worker-type": worker_type,
+            "dependencies": dependencies,
+            "if-dependencies": [dep_job.kind],
+            "attributes": attributes,
+            "run-on-projects": job.get(
+                "run-on-projects", dep_job.attributes.get("run_on_projects")
+            ),
+            "optimization": dep_job.optimization,
+            "treeherder": treeherder,
+            "routes": job.get("routes", []),
+            "extra": job.get("extra", {}),
+            "worker": worker,
+            "run": run,
+            "fetches": _generate_download_config(
+                config,
+                dep_job,
+                build_platform,
+                signing_task,
+                repackage_signing_task,
+                locale=locale,
+                existing_fetch=job.get("fetches"),
+            ),
+        }
+
+        if build_platform.startswith("macosx"):
+            task.setdefault("fetches", {}).setdefault("toolchain", []).extend(
+                [
+                    "linux64-libdmg",
+                    "linux64-hfsplus",
+                    "linux64-node",
+                    "linux64-xar",
+                    "linux64-mkbom",
+                ]
+            )
+
+        if "shipping-phase" in job:
+            task["shipping-phase"] = job["shipping-phase"]
+
+        yield task
+
+
+def _generate_download_config(
+    config,
+    task,
+    build_platform,
+    signing_task,
+    repackage_signing_task,
+    locale=None,
+    existing_fetch=None,
+):
+    locale_path = f"{locale}/" if locale else ""
+    fetch = {}
+    if existing_fetch:
+        fetch.update(existing_fetch)
+
+    if repackage_signing_task and build_platform.startswith("win"):
+        fetch.update(
+            {
+                repackage_signing_task: [f"{locale_path}target.installer.exe"],
+            }
+        )
+    elif build_platform.startswith("linux") or build_platform.startswith("macosx"):
+        signing_fetch = [
+            {
+                "artifact": "{}target{}".format(
+                    locale_path, archive_format(build_platform)
+                ),
+                "extract": False,
+            },
+        ]
+        if config.kind == "repackage-deb-l10n":
+            signing_fetch.append(
+                {
+                    "artifact": f"{locale_path}target.langpack.xpi",
+                    "extract": False,
+                }
+            )
+        fetch.update({signing_task: signing_fetch})
+    elif build_platform.startswith("win"):
+        fetch.update(
+            {
+                signing_task: [
+                    {
+                        "artifact": f"{locale_path}target.zip",
+                        "extract": False,
+                    },
+                    f"{locale_path}setup.exe",
+                ],
+            }
+        )
+
+        use_stub = task.attributes.get("stub-installer")
+        if use_stub:
+            fetch[signing_task].append(f"{locale_path}setup-stub.exe")
+
+    if fetch:
+        return fetch
+
+    raise NotImplementedError(f'Unsupported build_platform: "{build_platform}"')
+
+
+def _generate_task_output_files(
+    task, worker_implementation, repackage_config, locale=None
+):
+    locale_output_path = f"{locale}/" if locale else ""
+    artifact_prefix = get_artifact_prefix(task)
+
+    if worker_implementation == ("docker-worker", "linux"):
+        local_prefix = "/builds/worker/workspace/"
+    elif worker_implementation == ("generic-worker", "windows"):
+        local_prefix = "workspace/"
+    else:
+        raise NotImplementedError(
+            f'Unsupported worker implementation: "{worker_implementation}"'
+        )
+
+    output_files = []
+    for config in repackage_config:
+        output_files.append(
+            {
+                "type": "file",
+                "path": "{}outputs/{}{}".format(
+                    local_prefix, locale_output_path, config["output"]
+                ),
+                "name": "{}/{}{}".format(
+                    artifact_prefix, locale_output_path, config["output"]
+                ),
+            }
+        )
+    return output_files
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_l10n.py b/taskcluster/gecko_taskgraph/transforms/repackage_l10n.py
new file mode 100644
index 0000000000..e0f46e6fdc
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_l10n.py
@@ -0,0 +1,26 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage task into an actual task description.
+"""
+
+
+from taskgraph.transforms.base import TransformSequence
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def split_locales(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        for locale in dep_job.attributes.get("chunk_locales", []):
+            locale_job = copy_task(job)  # don't overwrite dict values here
+            treeherder = locale_job.setdefault("treeherder", {})
+            treeherder_group = locale_job.pop("treeherder-group")
+            treeherder["symbol"] = f"{treeherder_group}({locale})"
+            locale_job["locale"] = locale
+            yield locale_job
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_partner.py b/taskcluster/gecko_taskgraph/transforms/repackage_partner.py
new file mode 100644
index 0000000000..582a86dfad
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_partner.py
@@ -0,0 +1,302 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage task into an actual task description.
+"""
+
+
+import copy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.repackage import (
+    PACKAGE_FORMATS as PACKAGE_FORMATS_VANILLA,
+)
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.partners import get_partner_config_by_kind
+from gecko_taskgraph.util.platforms import archive_format, executable_extension
+from gecko_taskgraph.util.workertypes import worker_type_implementation
+
+
+def _by_platform(arg):
+    return optionally_keyed_by("build-platform", arg)
+
+
+# When repacking the stub installer we need to pass a zip file and package name to the
+# repackage task. This is not needed for vanilla stub but analogous to the full installer.
+PACKAGE_FORMATS = copy.deepcopy(PACKAGE_FORMATS_VANILLA)
+PACKAGE_FORMATS["installer-stub"]["inputs"]["package"] = "target-stub{archive_format}"
+PACKAGE_FORMATS["installer-stub"]["args"].extend(["--package-name", "{package-name}"])
+
+packaging_description_schema = schema.extend(
+    {
+        # unique label to describe this repackaging task
+        Optional("label"): str,
+        # Routes specific to this task, if defined
+        Optional("routes"): [str],
+        # passed through directly to the job description
+        Optional("extra"): task_description_schema["extra"],
+        # Shipping product and phase
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Required("package-formats"): _by_platform([str]),
+        # All l10n jobs use mozharness
+        Required("mozharness"): {
+            # Config files passed to the mozharness script
+            Required("config"): _by_platform([str]),
+            # Additional paths to look for mozharness configs in. These should be
+            # relative to the base of the source checkout
+            Optional("config-paths"): [str],
+            # if true, perform a checkout of a comm-central based branch inside the
+            # gecko checkout
+            Optional("comm-checkout"): bool,
+        },
+        # Override the default priority for the project
+        Optional("priority"): task_description_schema["priority"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(packaging_description_schema)
+
+
+@transforms.add
+def copy_in_useful_magic(config, jobs):
+    """Copy attributes from upstream task to be used for keyed configuration."""
+    for job in jobs:
+        dep = job["primary-dependency"]
+        job["build-platform"] = dep.attributes.get("build_platform")
+        yield job
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by platform, etc."""
+    fields = [
+        "mozharness.config",
+        "package-formats",
+    ]
+    for job in jobs:
+        job = copy.deepcopy(job)  # don't overwrite dict values here
+        for field in fields:
+            resolve_keyed_by(item=job, field=field, item_name="?")
+        yield job
+
+
+@transforms.add
+def make_repackage_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+
+        label = job.get("label", dep_job.label.replace("signing-", "repackage-"))
+        job["label"] = label
+
+        yield job
+
+
+@transforms.add
+def make_job_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        build_platform = attributes["build_platform"]
+
+        if job["build-platform"].startswith("win"):
+            if dep_job.kind.endswith("signing"):
+                continue
+        if job["build-platform"].startswith("macosx"):
+            if dep_job.kind.endswith("repack"):
+                continue
+        dependencies = {dep_job.attributes.get("kind"): dep_job.label}
+        dependencies.update(dep_job.dependencies)
+
+        signing_task = None
+        for dependency in dependencies.keys():
+            if build_platform.startswith("macosx") and dependency.endswith("signing"):
+                signing_task = dependency
+            elif build_platform.startswith("win") and dependency.endswith("repack"):
+                signing_task = dependency
+
+        attributes["repackage_type"] = "repackage"
+
+        repack_id = job["extra"]["repack_id"]
+
+        partner_config = get_partner_config_by_kind(config, config.kind)
+        partner, subpartner, _ = repack_id.split("/")
+        repack_stub_installer = partner_config[partner][subpartner].get(
+            "repack_stub_installer"
+        )
+        if build_platform.startswith("win32") and repack_stub_installer:
+            job["package-formats"].append("installer-stub")
+
+        repackage_config = []
+        for format in job.get("package-formats"):
+            command = copy.deepcopy(PACKAGE_FORMATS[format])
+            substs = {
+                "archive_format": archive_format(build_platform),
+                "executable_extension": executable_extension(build_platform),
+            }
+            command["inputs"] = {
+                name: filename.format(**substs)
+                for name, filename in command["inputs"].items()
+            }
+            repackage_config.append(command)
+
+        run = job.get("mozharness", {})
+        run.update(
+            {
+                "using": "mozharness",
+                "script": "mozharness/scripts/repackage.py",
+                "job-script": "taskcluster/scripts/builder/repackage.sh",
+                "actions": ["setup", "repackage"],
+                "extra-config": {
+                    "repackage_config": repackage_config,
+                },
+            }
+        )
+
+        worker = {
+            "chain-of-trust": True,
+            "max-run-time": 3600,
+            "taskcluster-proxy": True if get_artifact_prefix(dep_job) else False,
+            "env": {
+                "REPACK_ID": repack_id,
+            },
+            # Don't add generic artifact directory.
+            "skip-artifacts": True,
+        }
+
+        worker_type = "b-linux-gcp"
+        worker["docker-image"] = {"in-tree": "debian11-amd64-build"}
+
+        worker["artifacts"] = _generate_task_output_files(
+            dep_job,
+            worker_type_implementation(config.graph_config, config.params, worker_type),
+            repackage_config,
+            partner=repack_id,
+        )
+
+        description = (
+            "Repackaging for repack_id '{repack_id}' for build '"
+            "{build_platform}/{build_type}'".format(
+                repack_id=job["extra"]["repack_id"],
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        task = {
+            "label": job["label"],
+            "description": description,
+            "worker-type": worker_type,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "scopes": ["queue:get-artifact:releng/partner/*"],
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "routes": job.get("routes", []),
+            "extra": job.get("extra", {}),
+            "worker": worker,
+            "run": run,
+            "fetches": _generate_download_config(
+                dep_job,
+                build_platform,
+                signing_task,
+                partner=repack_id,
+                project=config.params["project"],
+                repack_stub_installer=repack_stub_installer,
+            ),
+        }
+
+        # we may have reduced the priority for partner jobs, otherwise task.py will set it
+        if job.get("priority"):
+            task["priority"] = job["priority"]
+        if build_platform.startswith("macosx"):
+            task.setdefault("fetches", {}).setdefault("toolchain", []).extend(
+                [
+                    "linux64-libdmg",
+                    "linux64-hfsplus",
+                    "linux64-node",
+                ]
+            )
+        yield task
+
+
+def _generate_download_config(
+    task,
+    build_platform,
+    signing_task,
+    partner=None,
+    project=None,
+    repack_stub_installer=False,
+):
+    locale_path = f"{partner}/" if partner else ""
+
+    if build_platform.startswith("macosx"):
+        return {
+            signing_task: [
+                {
+                    "artifact": f"{locale_path}target.tar.gz",
+                    "extract": False,
+                },
+            ],
+        }
+    if build_platform.startswith("win"):
+        download_config = [
+            {
+                "artifact": f"{locale_path}target.zip",
+                "extract": False,
+            },
+            f"{locale_path}setup.exe",
+        ]
+        if build_platform.startswith("win32") and repack_stub_installer:
+            download_config.extend(
+                [
+                    {
+                        "artifact": f"{locale_path}target-stub.zip",
+                        "extract": False,
+                    },
+                    f"{locale_path}setup-stub.exe",
+                ]
+            )
+        return {signing_task: download_config}
+
+    raise NotImplementedError(f'Unsupported build_platform: "{build_platform}"')
+
+
+def _generate_task_output_files(task, worker_implementation, repackage_config, partner):
+    """We carefully generate an explicit list here, but there's an artifacts directory
+    too, courtesy of generic_worker_add_artifacts() (windows) or docker_worker_add_artifacts().
+    Any errors here are likely masked by that.
+    """
+    partner_output_path = f"{partner}/"
+    artifact_prefix = get_artifact_prefix(task)
+
+    if worker_implementation == ("docker-worker", "linux"):
+        local_prefix = "/builds/worker/workspace/"
+    elif worker_implementation == ("generic-worker", "windows"):
+        local_prefix = "workspace/"
+    else:
+        raise NotImplementedError(
+            f'Unsupported worker implementation: "{worker_implementation}"'
+        )
+
+    output_files = []
+    for config in repackage_config:
+        output_files.append(
+            {
+                "type": "file",
+                "path": "{}outputs/{}{}".format(
+                    local_prefix, partner_output_path, config["output"]
+                ),
+                "name": "{}/{}{}".format(
+                    artifact_prefix, partner_output_path, config["output"]
+                ),
+            }
+        )
+    return output_files
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_routes.py b/taskcluster/gecko_taskgraph/transforms/repackage_routes.py
new file mode 100644
index 0000000000..2973ee35bd
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_routes.py
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Add indexes to repackage kinds
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_indexes(config, jobs):
+    for job in jobs:
+        repackage_type = job["attributes"].get("repackage_type")
+        if repackage_type and job["attributes"]["build_type"] != "debug":
+            build_platform = job["attributes"]["build_platform"]
+            job_name = f"{build_platform}-{repackage_type}"
+            product = job.get("index", {}).get("product", "firefox")
+            index_type = "generic"
+            if job["attributes"].get("shippable") and job["attributes"].get("locale"):
+                index_type = "shippable-l10n"
+            if job["attributes"].get("shippable"):
+                index_type = "shippable"
+            if job["attributes"].get("locale"):
+                index_type = "l10n"
+            job["index"] = {
+                "job-name": job_name,
+                "product": product,
+                "type": index_type,
+            }
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_set_upstream_mac_kind.py b/taskcluster/gecko_taskgraph/transforms/repackage_set_upstream_mac_kind.py
new file mode 100644
index 0000000000..14c865eea5
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_set_upstream_mac_kind.py
@@ -0,0 +1,39 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform mac notarization tasks
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def repackage_set_upstream_mac_kind(config, tasks):
+    """
+    Notarization only runs on level 3
+    If level < 3 then repackage the mac-signing task artifact
+    Exception for debug builds, which will use signed build on level 3
+    """
+    for task in tasks:
+        if "macosx64" not in task["primary-dependency"].attributes["build_platform"]:
+            task.pop("upstream-mac-kind")
+            yield task
+            continue
+        resolve_keyed_by(
+            task,
+            "upstream-mac-kind",
+            item_name=config.kind,
+            **{
+                "build-type": task["primary-dependency"].attributes["build_type"],
+                "project": config.params.get("project"),
+            }
+        )
+        upstream_mac_kind = task.pop("upstream-mac-kind")
+
+        if task["primary-dependency"].kind != upstream_mac_kind:
+            continue
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_signing.py b/taskcluster/gecko_taskgraph/transforms/repackage_signing.py
new file mode 100644
index 0000000000..f98f8f0814
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_signing.py
@@ -0,0 +1,137 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage signing task into an actual task description.
+"""
+
+import os
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope_per_platform
+
+repackage_signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+SIGNING_FORMATS = {
+    "target.installer.exe": ["autograph_authenticode_sha2_stub"],
+    "target.stub-installer.exe": ["autograph_authenticode_sha2_stub"],
+    "target.installer.msi": ["autograph_authenticode_sha2"],
+    "target.installer.msix": ["autograph_authenticode_sha2"],
+}
+
+transforms = TransformSequence()
+transforms.add_validate(repackage_signing_description_schema)
+
+
+@transforms.add
+def make_repackage_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        locale = attributes.get("locale", dep_job.attributes.get("locale"))
+        attributes["repackage_type"] = "repackage-signing"
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "rs(B)")
+        dep_th_platform = dep_job.task.get("extra", {}).get("treeherder-platform")
+        treeherder.setdefault("platform", dep_th_platform)
+        treeherder.setdefault(
+            "tier", dep_job.task.get("extra", {}).get("treeherder", {}).get("tier", 1)
+        )
+        treeherder.setdefault("kind", "build")
+
+        if locale:
+            treeherder["symbol"] = f"rs({locale})"
+
+        if config.kind == "repackage-signing-msi":
+            treeherder["symbol"] = "MSIs({})".format(locale or "N")
+
+        elif config.kind in (
+            "repackage-signing-msix",
+            "repackage-signing-shippable-l10n-msix",
+        ):
+            # Like "MSIXs(Bs-multi)".
+            treeherder["symbol"] = "MSIXs({})".format(
+                dep_job.task.get("extra", {}).get("treeherder", {}).get("symbol", "B")
+            )
+
+        label = job["label"]
+
+        dep_kind = dep_job.kind
+        if "l10n" in dep_kind:
+            dep_kind = "repackage"
+
+        dependencies = {dep_kind: dep_job.label}
+
+        signing_dependencies = dep_job.dependencies
+        # This is so we get the build task etc in our dependencies to have better beetmover
+        # support.  But for multi-locale MSIX packages, we don't want the signing task to directly
+        # depend on the langpack tasks.
+        dependencies.update(
+            {
+                k: v
+                for k, v in signing_dependencies.items()
+                if k != "docker-image"
+                and not k.startswith("shippable-l10n-signing-linux64")
+            }
+        )
+
+        description = (
+            "Signing of repackaged artifacts for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=attributes.get("build_platform"),
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        build_platform = dep_job.attributes.get("build_platform")
+        is_shippable = dep_job.attributes.get("shippable")
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_shippable, config
+        )
+        scopes = [signing_cert_scope]
+
+        upstream_artifacts = []
+        for artifact in sorted(dep_job.attributes.get("release_artifacts")):
+            basename = os.path.basename(artifact)
+            if basename in SIGNING_FORMATS:
+                upstream_artifacts.append(
+                    {
+                        "taskId": {"task-reference": f"<{dep_kind}>"},
+                        "taskType": "repackage",
+                        "paths": [artifact],
+                        "formats": SIGNING_FORMATS[os.path.basename(artifact)],
+                    }
+                )
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "linux-signing" if is_shippable else "linux-depsigning",
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+                "max-run-time": 3600,
+            },
+            "scopes": scopes,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "optimization": dep_job.optimization,
+            "treeherder": treeherder,
+        }
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/repackage_signing_partner.py b/taskcluster/gecko_taskgraph/transforms/repackage_signing_partner.py
new file mode 100644
index 0000000000..eaf71f92a2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repackage_signing_partner.py
@@ -0,0 +1,145 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repackage signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.taskcluster import get_artifact_path
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.partners import get_partner_config_by_kind
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope_per_platform
+
+transforms = TransformSequence()
+
+repackage_signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("extra"): object,
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("priority"): task_description_schema["priority"],
+    }
+)
+
+transforms.add_validate(repackage_signing_description_schema)
+
+
+@transforms.add
+def make_repackage_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        repack_id = dep_job.task["extra"]["repack_id"]
+        attributes = dep_job.attributes
+        build_platform = dep_job.attributes.get("build_platform")
+        is_shippable = dep_job.attributes.get("shippable")
+
+        # Mac & windows
+        label = dep_job.label.replace("repackage-", "repackage-signing-")
+        # Linux
+        label = label.replace("chunking-dummy-", "repackage-signing-")
+        description = "Signing of repackaged artifacts for partner repack id '{repack_id}' for build '" "{build_platform}/{build_type}'".format(  # NOQA: E501
+            repack_id=repack_id,
+            build_platform=attributes.get("build_platform"),
+            build_type=attributes.get("build_type"),
+        )
+
+        if "linux" in build_platform:
+            # we want the repack job, via the dependencies for the the chunking-dummy dep_job
+            for dep in dep_job.dependencies.values():
+                if dep.startswith("release-partner-repack"):
+                    dependencies = {"repack": dep}
+                    break
+        else:
+            # we have a genuine repackage job as our parent
+            dependencies = {"repackage": dep_job.label}
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+        attributes["repackage_type"] = "repackage-signing"
+
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_shippable, config
+        )
+        scopes = [signing_cert_scope]
+
+        if "win" in build_platform:
+            upstream_artifacts = [
+                {
+                    "taskId": {"task-reference": "<repackage>"},
+                    "taskType": "repackage",
+                    "paths": [
+                        get_artifact_path(dep_job, f"{repack_id}/target.installer.exe"),
+                    ],
+                    "formats": ["autograph_authenticode_sha2", "autograph_gpg"],
+                }
+            ]
+
+            partner_config = get_partner_config_by_kind(config, config.kind)
+            partner, subpartner, _ = repack_id.split("/")
+            repack_stub_installer = partner_config[partner][subpartner].get(
+                "repack_stub_installer"
+            )
+            if build_platform.startswith("win32") and repack_stub_installer:
+                upstream_artifacts.append(
+                    {
+                        "taskId": {"task-reference": "<repackage>"},
+                        "taskType": "repackage",
+                        "paths": [
+                            get_artifact_path(
+                                dep_job,
+                                f"{repack_id}/target.stub-installer.exe",
+                            ),
+                        ],
+                        "formats": ["autograph_authenticode_sha2", "autograph_gpg"],
+                    }
+                )
+        elif "mac" in build_platform:
+            upstream_artifacts = [
+                {
+                    "taskId": {"task-reference": "<repackage>"},
+                    "taskType": "repackage",
+                    "paths": [
+                        get_artifact_path(dep_job, f"{repack_id}/target.dmg"),
+                    ],
+                    "formats": ["autograph_gpg"],
+                }
+            ]
+        elif "linux" in build_platform:
+            upstream_artifacts = [
+                {
+                    "taskId": {"task-reference": "<repack>"},
+                    "taskType": "repackage",
+                    "paths": [
+                        get_artifact_path(dep_job, f"{repack_id}/target.tar.bz2"),
+                    ],
+                    "formats": ["autograph_gpg"],
+                }
+            ]
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "linux-signing",
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+                "max-run-time": 3600,
+            },
+            "scopes": scopes,
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "extra": {
+                "repack_id": repack_id,
+            },
+        }
+        # we may have reduced the priority for partner jobs, otherwise task.py will set it
+        if job.get("priority"):
+            task["priority"] = job["priority"]
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/repo_update.py b/taskcluster/gecko_taskgraph/transforms/repo_update.py
new file mode 100644
index 0000000000..f4f135b585
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/repo_update.py
@@ -0,0 +1,25 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the repo-update task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def resolve_keys(config, tasks):
+    for task in tasks:
+        env = task["worker"].setdefault("env", {})
+        env["BRANCH"] = config.params["project"]
+        for envvar in env:
+            resolve_keyed_by(env, envvar, envvar, **config.params)
+
+        for envvar in list(env.keys()):
+            if not env.get(envvar):
+                del env[envvar]
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/reprocess_symbols.py b/taskcluster/gecko_taskgraph/transforms/reprocess_symbols.py
new file mode 100644
index 0000000000..5ad359bd5a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/reprocess_symbols.py
@@ -0,0 +1,67 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the reprocess-symbols task description template,
+taskcluster/ci/reprocess-symbols/job-template.yml into an actual task description.
+"""
+
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import inherit_treeherder_from_dep, join_symbol
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def fill_template(config, tasks):
+    for task in tasks:
+        assert len(task["dependent-tasks"]) == 2
+
+        build_dep = task["primary-dependency"]
+        upload_dep = None
+        for dep_idx in task["dependent-tasks"]:
+            dep = task["dependent-tasks"][dep_idx]
+            if dep_idx != build_dep:
+                upload_dep = dep
+
+        task.pop("dependent-tasks", None)
+
+        # Fill out the dynamic fields in the task description
+        task["label"] = build_dep.label + "-reprocess-symbols"
+        task["dependencies"] = {"build": build_dep.label, "upload": upload_dep.label}
+        task["worker"]["env"]["GECKO_HEAD_REPOSITORY"] = config.params[
+            "head_repository"
+        ]
+        task["worker"]["env"]["GECKO_HEAD_REV"] = config.params["head_rev"]
+        task["worker"]["env"]["CRASHSTATS_SECRET"] = task["worker"]["env"][
+            "CRASHSTATS_SECRET"
+        ].format(level=config.params["level"])
+
+        attributes = copy_attributes_from_dependent_job(build_dep)
+        attributes.update(task.get("attributes", {}))
+        task["attributes"] = attributes
+
+        treeherder = inherit_treeherder_from_dep(task, build_dep)
+        th = build_dep.task.get("extra")["treeherder"]
+        th_symbol = th.get("symbol")
+        th_groupsymbol = th.get("groupSymbol", "?")
+
+        # Disambiguate the treeherder symbol.
+        sym = "Rep" + (th_symbol[1:] if th_symbol.startswith("B") else th_symbol)
+        treeherder.setdefault("symbol", join_symbol(th_groupsymbol, sym))
+        task["treeherder"] = treeherder
+
+        task["run-on-projects"] = build_dep.attributes.get("run_on_projects")
+        task["optimization"] = {"reprocess-symbols": None}
+        task["if-dependencies"] = ["build"]
+
+        del task["primary-dependency"]
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/reverse_chunk_deps.py b/taskcluster/gecko_taskgraph/transforms/reverse_chunk_deps.py
new file mode 100644
index 0000000000..ac2f282799
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/reverse_chunk_deps.py
@@ -0,0 +1,45 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Adjust dependencies to not exceed MAX_DEPENDENCIES
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import add_suffix
+
+import gecko_taskgraph.transforms.release_deps as release_deps
+from gecko_taskgraph import MAX_DEPENDENCIES
+from gecko_taskgraph.util.copy_task import copy_task
+
+transforms = TransformSequence()
+
+
+def yield_job(orig_job, deps, count):
+    job = copy_task(orig_job)
+    job["dependencies"] = deps
+    job["name"] = "{}-{}".format(orig_job["name"], count)
+    if "treeherder" in job:
+        job["treeherder"]["symbol"] = add_suffix(
+            job["treeherder"]["symbol"], f"-{count}"
+        )
+
+    return job
+
+
+@transforms.add
+def add_dependencies(config, jobs):
+    for job in release_deps.add_dependencies(config, jobs):
+        count = 1
+        deps = {}
+
+        # sort for deterministic chunking
+        for dep_label in sorted(job["dependencies"].keys()):
+            deps[dep_label] = dep_label
+            if len(deps) == MAX_DEPENDENCIES:
+                yield yield_job(job, deps, count)
+                deps = {}
+                count += 1
+        if deps:
+            yield yield_job(job, deps, count)
+            count += 1
diff --git a/taskcluster/gecko_taskgraph/transforms/run_pgo_profile.py b/taskcluster/gecko_taskgraph/transforms/run_pgo_profile.py
new file mode 100644
index 0000000000..2585bdd712
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/run_pgo_profile.py
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Apply some defaults and minor modifications to the pgo jobs.
+"""
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def run_profile_data(config, jobs):
+    for job in jobs:
+        build_platform = job["attributes"].get("build_platform")
+        instr = "instrumented-build-{}".format(job["name"])
+        if "android" in build_platform:
+            artifact = "geckoview-test_runner.apk"
+        elif "macosx64" in build_platform:
+            artifact = "target.dmg"
+        elif "win" in build_platform:
+            artifact = "target.zip"
+        else:
+            artifact = "target.tar.bz2"
+        job.setdefault("fetches", {})[instr] = [
+            artifact,
+            "target.crashreporter-symbols.zip",
+        ]
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/scriptworker.py b/taskcluster/gecko_taskgraph/transforms/scriptworker.py
new file mode 100644
index 0000000000..5d382702af
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/scriptworker.py
@@ -0,0 +1,18 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Transforms for adding appropriate scopes to scriptworker tasks.
+"""
+
+
+from gecko_taskgraph.util.scriptworker import get_balrog_server_scope
+
+
+def add_balrog_scopes(config, jobs):
+    for job in jobs:
+        server_scope = get_balrog_server_scope(config)
+        job["scopes"] = [server_scope]
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/scriptworker_canary.py b/taskcluster/gecko_taskgraph/transforms/scriptworker_canary.py
new file mode 100644
index 0000000000..43735f3dce
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/scriptworker_canary.py
@@ -0,0 +1,46 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Build a command to run `mach release push-scriptworker-canaries`.
+"""
+
+
+from pipes import quote as shell_quote
+
+from mozrelease.scriptworker_canary import TASK_TYPES
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def build_command(config, jobs):
+    scriptworkers = config.params["try_task_config"].get(
+        "scriptworker-canary-workers", []
+    )
+    # Filter the list of workers to those we have configured a set of canary
+    # tasks for.
+    scriptworkers = [
+        scriptworker for scriptworker in scriptworkers if scriptworker in TASK_TYPES
+    ]
+
+    if not scriptworkers:
+        return
+
+    for job in jobs:
+
+        command = ["release", "push-scriptworker-canary"]
+        for scriptworker in scriptworkers:
+            command.extend(["--scriptworker", scriptworker])
+        for address in job.pop("addresses"):
+            command.extend(["--address", address])
+        if "ssh-key-secret" in job:
+            ssh_key_secret = job.pop("ssh-key-secret")
+            command.extend(["--ssh-key-secret", ssh_key_secret])
+            job.setdefault("scopes", []).append(f"secrets:get:{ssh_key_secret}")
+
+        job.setdefault("run", {}).update(
+            {"using": "mach", "mach": " ".join(map(shell_quote, command))}
+        )
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/sentry.py b/taskcluster/gecko_taskgraph/transforms/sentry.py
new file mode 100644
index 0000000000..2e43a15518
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/sentry.py
@@ -0,0 +1,30 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def sentry(config, tasks):
+    """Do transforms specific to github-sync tasks."""
+    if config.params["project"] not in ["mozilla-central", "try"]:
+        return
+    for task in tasks:
+        scopes = [
+            scope.format(level=config.params["level"]) for scope in task["scopes"]
+        ]
+        task["scopes"] = scopes
+
+        env = {
+            key: value.format(
+                level=config.params["level"],
+                head_repository=config.params["head_repository"],
+                head_rev=config.params["head_rev"],
+            )
+            for (key, value) in task["worker"]["env"].items()
+        }
+        task["worker"]["env"] = env
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/shippable_l10n_signing.py b/taskcluster/gecko_taskgraph/transforms/shippable_l10n_signing.py
new file mode 100644
index 0000000000..324efa92dd
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/shippable_l10n_signing.py
@@ -0,0 +1,86 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import join_symbol
+
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.signed_artifacts import (
+    generate_specifications_of_artifacts_to_sign,
+)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def make_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        job["depname"] = dep_job.label
+
+        # add the chunk number to the TH symbol
+        symbol = job.get("treeherder", {}).get("symbol", "Bs")
+        symbol = "{}{}".format(symbol, dep_job.attributes.get("l10n_chunk"))
+        group = "L10n"
+
+        job["treeherder"] = {
+            "symbol": join_symbol(group, symbol),
+        }
+
+        yield job
+
+
+@transforms.add
+def define_upstream_artifacts(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        upstream_artifact_task = job.pop("upstream-artifact-task", dep_job)
+
+        job["attributes"] = copy_attributes_from_dependent_job(dep_job)
+        if dep_job.attributes.get("chunk_locales"):
+            # Used for l10n attribute passthrough
+            job["attributes"]["chunk_locales"] = dep_job.attributes.get("chunk_locales")
+
+        locale_specifications = generate_specifications_of_artifacts_to_sign(
+            config,
+            job,
+            keep_locale_template=True,
+            dep_kind=upstream_artifact_task.kind,
+        )
+
+        upstream_artifacts = []
+        for spec in locale_specifications:
+            upstream_task_type = "l10n"
+            if upstream_artifact_task.kind.endswith(
+                ("-mac-notarization", "-mac-signing")
+            ):
+                # Upstream is mac signing or notarization
+                upstream_task_type = "scriptworker"
+            upstream_artifacts.append(
+                {
+                    "taskId": {"task-reference": f"<{upstream_artifact_task.kind}>"},
+                    "taskType": upstream_task_type,
+                    # Set paths based on artifacts in the specs (above) one per
+                    # locale present in the chunk this is signing stuff for.
+                    # Pass paths through set and sorted() so we get a list back
+                    # and we remove any duplicates (e.g. hardcoded ja-JP-mac langpack)
+                    "paths": sorted(
+                        {
+                            path_template.format(locale=locale)
+                            for locale in upstream_artifact_task.attributes.get(
+                                "chunk_locales", []
+                            )
+                            for path_template in spec["artifacts"]
+                        }
+                    ),
+                    "formats": spec["formats"],
+                }
+            )
+
+        job["upstream-artifacts"] = upstream_artifacts
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/signing.py b/taskcluster/gecko_taskgraph/transforms/signing.py
new file mode 100644
index 0000000000..9a5873fc81
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/signing.py
@@ -0,0 +1,266 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.keyed_by import evaluate_keyed_by
+from taskgraph.util.schema import taskref_or_string
+from voluptuous import Optional, Required
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import (
+    copy_attributes_from_dependent_job,
+    release_level,
+)
+from gecko_taskgraph.util.scriptworker import (
+    add_scope_prefix,
+    get_signing_cert_scope_per_platform,
+)
+
+transforms = TransformSequence()
+
+signing_description_schema = schema.extend(
+    {
+        # Artifacts from dep task to sign - Sync with taskgraph/transforms/task.py
+        # because this is passed directly into the signingscript worker
+        Required("upstream-artifacts"): [
+            {
+                # taskId of the task with the artifact
+                Required("taskId"): taskref_or_string,
+                # type of signing task (for CoT)
+                Required("taskType"): str,
+                # Paths to the artifacts to sign
+                Required("paths"): [str],
+                # Signing formats to use on each of the paths
+                Required("formats"): [str],
+            }
+        ],
+        # depname is used in taskref's to identify the taskID of the unsigned things
+        Required("depname"): str,
+        # attributes for this task
+        Optional("attributes"): {str: object},
+        # unique label to describe this signing task, defaults to {dep.label}-signing
+        Optional("label"): str,
+        # treeherder is allowed here to override any defaults we use for signing.  See
+        # taskcluster/gecko_taskgraph/transforms/task.py for the schema details, and the
+        # below transforms for defaults of various values.
+        Optional("treeherder"): task_description_schema["treeherder"],
+        # Routes specific to this task, if defined
+        Optional("routes"): [str],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("dependent-tasks"): {str: object},
+        # Optional control for how long a task may run (aka maxRunTime)
+        Optional("max-run-time"): int,
+        Optional("extra"): {str: object},
+        # Max number of partner repacks per chunk
+        Optional("repacks-per-chunk"): int,
+        # Override the default priority for the project
+        Optional("priority"): task_description_schema["priority"],
+    }
+)
+
+
+@transforms.add
+def set_defaults(config, jobs):
+    for job in jobs:
+        if not job.get("depname"):
+            dep_job = job["primary-dependency"]
+            job["depname"] = dep_job.kind
+        yield job
+
+
+transforms.add_validate(signing_description_schema)
+
+
+@transforms.add
+def add_entitlements_link(config, jobs):
+    for job in jobs:
+        entitlements_path = evaluate_keyed_by(
+            config.graph_config["mac-notarization"]["mac-entitlements"],
+            "mac entitlements",
+            {
+                "platform": job["primary-dependency"].attributes.get("build_platform"),
+                "release-level": release_level(config.params["project"]),
+            },
+        )
+        if entitlements_path:
+            job["entitlements-url"] = config.params.file_url(
+                entitlements_path,
+            )
+        yield job
+
+
+@transforms.add
+def add_requirements_link(config, jobs):
+    for job in jobs:
+        requirements_path = evaluate_keyed_by(
+            config.graph_config["mac-notarization"]["mac-requirements"],
+            "mac requirements",
+            {
+                "platform": job["primary-dependency"].attributes.get("build_platform"),
+            },
+        )
+        if requirements_path:
+            job["requirements-plist-url"] = config.params.file_url(
+                requirements_path,
+            )
+        yield job
+
+
+@transforms.add
+def make_task_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        signing_format_scopes = []
+        formats = set()
+        for artifacts in job["upstream-artifacts"]:
+            for f in artifacts["formats"]:
+                formats.add(f)  # Add each format only once
+
+        is_shippable = dep_job.attributes.get("shippable", False)
+        build_platform = dep_job.attributes.get("build_platform")
+        treeherder = None
+        if "partner" not in config.kind and "eme-free" not in config.kind:
+            treeherder = job.get("treeherder", {})
+
+            dep_th_platform = (
+                dep_job.task.get("extra", {})
+                .get("treeherder", {})
+                .get("machine", {})
+                .get("platform", "")
+            )
+            build_type = dep_job.attributes.get("build_type")
+            treeherder.setdefault(
+                "platform",
+                _generate_treeherder_platform(
+                    dep_th_platform, build_platform, build_type
+                ),
+            )
+
+            # ccov builds are tier 2, so they cannot have tier 1 tasks
+            # depending on them.
+            treeherder.setdefault(
+                "tier",
+                dep_job.task.get("extra", {}).get("treeherder", {}).get("tier", 1),
+            )
+            treeherder.setdefault(
+                "symbol",
+                _generate_treeherder_symbol(
+                    dep_job.task.get("extra", {}).get("treeherder", {}).get("symbol")
+                ),
+            )
+            treeherder.setdefault("kind", "build")
+
+        label = job["label"]
+        description = (
+            "Initial Signing for locale '{locale}' for build '"
+            "{build_platform}/{build_type}'".format(
+                locale=attributes.get("locale", "en-US"),
+                build_platform=build_platform,
+                build_type=attributes.get("build_type"),
+            )
+        )
+
+        attributes = (
+            job["attributes"]
+            if job.get("attributes")
+            else copy_attributes_from_dependent_job(dep_job)
+        )
+        attributes["signed"] = True
+
+        if "linux" in build_platform:
+            attributes["release_artifacts"] = ["public/build/KEY"]
+
+        if dep_job.attributes.get("chunk_locales"):
+            # Used for l10n attribute passthrough
+            attributes["chunk_locales"] = dep_job.attributes.get("chunk_locales")
+
+        signing_cert_scope = get_signing_cert_scope_per_platform(
+            build_platform, is_shippable, config
+        )
+        worker_type_alias = "linux-signing" if is_shippable else "linux-depsigning"
+        task = {
+            "label": label,
+            "description": description,
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": job["upstream-artifacts"],
+                "max-run-time": job.get("max-run-time", 3600),
+            },
+            "scopes": [signing_cert_scope] + signing_format_scopes,
+            "dependencies": _generate_dependencies(job),
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "optimization": dep_job.optimization,
+            "routes": job.get("routes", []),
+            "shipping-product": job.get("shipping-product"),
+            "shipping-phase": job.get("shipping-phase"),
+        }
+        if dep_job.kind in task["dependencies"]:
+            task["if-dependencies"] = [dep_job.kind]
+
+        # build-mac-{signing,notarization} uses signingscript instead of iscript
+        if "macosx" in build_platform and config.kind.endswith("-mac-notarization"):
+            task["worker"]["mac-behavior"] = "apple_notarization"
+            task["scopes"] = [
+                add_scope_prefix(config, "signing:cert:release-apple-notarization")
+            ]
+        elif "macosx" in build_platform:
+            # iscript overrides
+            task["worker"]["mac-behavior"] = "mac_sign_and_pkg"
+
+            worker_type_alias_map = {
+                "linux-depsigning": "mac-depsigning",
+                "linux-signing": "mac-signing",
+            }
+            assert worker_type_alias in worker_type_alias_map, (
+                "Make sure to adjust the below worker_type_alias logic for "
+                "mac if you change the signing workerType aliases!"
+                " ({} not found in mapping)".format(worker_type_alias)
+            )
+            worker_type_alias = worker_type_alias_map[worker_type_alias]
+            for attr in ("entitlements-url", "requirements-plist-url"):
+                if job.get(attr):
+                    task["worker"][attr] = job[attr]
+
+        task["worker-type"] = worker_type_alias
+        if treeherder:
+            task["treeherder"] = treeherder
+        if job.get("extra"):
+            task["extra"] = job["extra"]
+        # we may have reduced the priority for partner jobs, otherwise task.py will set it
+        if job.get("priority"):
+            task["priority"] = job["priority"]
+
+        yield task
+
+
+def _generate_dependencies(job):
+    if isinstance(job.get("dependent-tasks"), dict):
+        deps = {}
+        for k, v in job["dependent-tasks"].items():
+            deps[k] = v.label
+        return deps
+    return {job["depname"]: job["primary-dependency"].label}
+
+
+def _generate_treeherder_platform(dep_th_platform, build_platform, build_type):
+    if "-pgo" in build_platform:
+        actual_build_type = "pgo"
+    elif "-ccov" in build_platform:
+        actual_build_type = "ccov"
+    else:
+        actual_build_type = build_type
+    return f"{dep_th_platform}/{actual_build_type}"
+
+
+def _generate_treeherder_symbol(build_symbol):
+    symbol = build_symbol + "s"
+    return symbol
diff --git a/taskcluster/gecko_taskgraph/transforms/source_checksums_signing.py b/taskcluster/gecko_taskgraph/transforms/source_checksums_signing.py
new file mode 100644
index 0000000000..60c5f30ed3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/source_checksums_signing.py
@@ -0,0 +1,83 @@
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the checksums signing task into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+from voluptuous import Optional
+
+from gecko_taskgraph.loader.single_dep import schema
+from gecko_taskgraph.transforms.task import task_description_schema
+from gecko_taskgraph.util.attributes import copy_attributes_from_dependent_job
+from gecko_taskgraph.util.scriptworker import get_signing_cert_scope
+
+checksums_signing_description_schema = schema.extend(
+    {
+        Optional("label"): str,
+        Optional("treeherder"): task_description_schema["treeherder"],
+        Optional("shipping-product"): task_description_schema["shipping-product"],
+        Optional("shipping-phase"): task_description_schema["shipping-phase"],
+    }
+)
+
+transforms = TransformSequence()
+transforms.add_validate(checksums_signing_description_schema)
+
+
+@transforms.add
+def make_checksums_signing_description(config, jobs):
+    for job in jobs:
+        dep_job = job["primary-dependency"]
+        attributes = dep_job.attributes
+
+        treeherder = job.get("treeherder", {})
+        treeherder.setdefault("symbol", "css(N)")
+        dep_th_platform = (
+            dep_job.task.get("extra", {})
+            .get("treeherder", {})
+            .get("machine", {})
+            .get("platform", "")
+        )
+        treeherder.setdefault("platform", f"{dep_th_platform}/opt")
+        treeherder.setdefault("tier", 1)
+        treeherder.setdefault("kind", "build")
+
+        label = job["label"]
+        description = "Signing of release-source checksums file"
+        dependencies = {"beetmover": dep_job.label}
+
+        attributes = copy_attributes_from_dependent_job(dep_job)
+
+        upstream_artifacts = [
+            {
+                "taskId": {"task-reference": "<beetmover>"},
+                "taskType": "beetmover",
+                "paths": [
+                    "public/target-source.checksums",
+                ],
+                "formats": ["autograph_gpg"],
+            }
+        ]
+
+        signing_cert_scope = get_signing_cert_scope(config)
+
+        task = {
+            "label": label,
+            "description": description,
+            "worker-type": "linux-signing",
+            "worker": {
+                "implementation": "scriptworker-signing",
+                "upstream-artifacts": upstream_artifacts,
+                "max-run-time": 3600,
+            },
+            "scopes": [
+                signing_cert_scope,
+            ],
+            "dependencies": dependencies,
+            "attributes": attributes,
+            "run-on-projects": dep_job.attributes.get("run_on_projects"),
+            "treeherder": treeherder,
+        }
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/source_test.py b/taskcluster/gecko_taskgraph/transforms/source_test.py
new file mode 100644
index 0000000000..b480fcad02
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/source_test.py
@@ -0,0 +1,270 @@
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Source-test jobs can run on multiple platforms.  These transforms allow jobs
+with either `platform` or a list of `platforms`, and set the appropriate
+treeherder configuration and attributes for that platform.
+"""
+
+
+import copy
+import os
+
+import taskgraph
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.attributes import keymatch
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import join_symbol, split_symbol
+from voluptuous import Any, Extra, Optional, Required
+
+from gecko_taskgraph.transforms.job import job_description_schema
+from gecko_taskgraph.util.hg import get_json_automationrelevance
+
+source_test_description_schema = Schema(
+    {
+        # most fields are passed directly through as job fields, and are not
+        # repeated here
+        Extra: object,
+        # The platform on which this task runs.  This will be used to set up attributes
+        # (for try selection) and treeherder metadata (for display).  If given as a list,
+        # the job will be "split" into multiple tasks, one with each platform.
+        Required("platform"): Any(str, [str]),
+        # Build labels required for the task. If this key is provided it must
+        # contain a build label for the task platform.
+        # The task will then depend on a build task, and the installer url will be
+        # saved to the GECKO_INSTALLER_URL environment variable.
+        Optional("require-build"): optionally_keyed_by("project", {str: str}),
+        # These fields can be keyed by "platform", and are otherwise identical to
+        # job descriptions.
+        Required("worker-type"): optionally_keyed_by(
+            "platform", job_description_schema["worker-type"]
+        ),
+        Required("worker"): optionally_keyed_by(
+            "platform", job_description_schema["worker"]
+        ),
+        Optional("python-version"): [int],
+        Optional("dependencies"): {
+            k: optionally_keyed_by("platform", v)
+            for k, v in job_description_schema["dependencies"].items()
+        },
+        # A list of artifacts to install from 'fetch' tasks.
+        Optional("fetches"): {
+            str: optionally_keyed_by(
+                "platform", job_description_schema["fetches"][str]
+            ),
+        },
+    }
+)
+
+transforms = TransformSequence()
+
+transforms.add_validate(source_test_description_schema)
+
+
+@transforms.add
+def set_job_name(config, jobs):
+    for job in jobs:
+        if "job-from" in job and job["job-from"] != "kind.yml":
+            from_name = os.path.splitext(job["job-from"])[0]
+            job["name"] = "{}-{}".format(from_name, job["name"])
+        yield job
+
+
+@transforms.add
+def expand_platforms(config, jobs):
+    for job in jobs:
+        if isinstance(job["platform"], str):
+            yield job
+            continue
+
+        for platform in job["platform"]:
+            pjob = copy.deepcopy(job)
+            pjob["platform"] = platform
+
+            if "name" in pjob:
+                pjob["name"] = "{}-{}".format(pjob["name"], platform)
+            else:
+                pjob["label"] = "{}-{}".format(pjob["label"], platform)
+            yield pjob
+
+
+@transforms.add
+def split_python(config, jobs):
+    for job in jobs:
+        key = "python-version"
+        versions = job.pop(key, [])
+        if not versions:
+            yield job
+            continue
+        for version in versions:
+            group = f"py{version}"
+            pyjob = copy.deepcopy(job)
+            if "name" in pyjob:
+                pyjob["name"] += f"-{group}"
+            else:
+                pyjob["label"] += f"-{group}"
+            symbol = split_symbol(pyjob["treeherder"]["symbol"])[1]
+            pyjob["treeherder"]["symbol"] = join_symbol(group, symbol)
+            pyjob["run"][key] = version
+            yield pyjob
+
+
+@transforms.add
+def split_jsshell(config, jobs):
+    all_shells = {"sm": "Spidermonkey", "v8": "Google V8"}
+
+    for job in jobs:
+        if not job["name"].startswith("jsshell"):
+            yield job
+            continue
+
+        test = job.pop("test")
+        for shell in job.get("shell", all_shells.keys()):
+            assert shell in all_shells
+
+            new_job = copy.deepcopy(job)
+            new_job["name"] = "{}-{}".format(new_job["name"], shell)
+            new_job["description"] = "{} on {}".format(
+                new_job["description"], all_shells[shell]
+            )
+            new_job["shell"] = shell
+
+            group = f"js-bench-{shell}"
+            symbol = split_symbol(new_job["treeherder"]["symbol"])[1]
+            new_job["treeherder"]["symbol"] = join_symbol(group, symbol)
+
+            run = new_job["run"]
+            run["mach"] = run["mach"].format(
+                shell=shell, SHELL=shell.upper(), test=test
+            )
+            yield new_job
+
+
+def add_build_dependency(config, job):
+    """
+    Add build dependency to the job and installer_url to env.
+    """
+    key = job["platform"]
+    build_labels = job.pop("require-build", {})
+    matches = keymatch(build_labels, key)
+    if not matches:
+        raise Exception(
+            "No build platform found. "
+            "Define 'require-build' for {} in the task config.".format(key)
+        )
+
+    if len(matches) > 1:
+        raise Exception(f"More than one build platform found for '{key}'.")
+
+    label = matches[0]
+    deps = job.setdefault("dependencies", {})
+    deps.update({"build": label})
+
+
+@transforms.add
+def handle_platform(config, jobs):
+    """
+    Handle the 'platform' property, setting up treeherder context as well as
+    try-related attributes.
+    """
+    fields = [
+        "always-target",
+        "fetches.toolchain",
+        "require-build",
+        "worker-type",
+        "worker",
+    ]
+
+    for job in jobs:
+        platform = job["platform"]
+
+        for field in fields:
+            resolve_keyed_by(
+                job, field, item_name=job["name"], project=config.params["project"]
+            )
+        for field in job.get("dependencies", {}):
+            resolve_keyed_by(
+                job,
+                f"dependencies.{field}",
+                item_name=job["name"],
+                project=config.params["project"],
+            )
+
+        if "treeherder" in job:
+            job["treeherder"].setdefault("platform", platform)
+
+        if "require-build" in job:
+            add_build_dependency(config, job)
+
+        del job["platform"]
+        yield job
+
+
+@transforms.add
+def handle_shell(config, jobs):
+    """
+    Handle the 'shell' property.
+    """
+    fields = [
+        "run-on-projects",
+        "worker.env",
+    ]
+
+    for job in jobs:
+        if not job.get("shell"):
+            yield job
+            continue
+
+        for field in fields:
+            resolve_keyed_by(job, field, item_name=job["name"])
+
+        del job["shell"]
+        yield job
+
+
+@transforms.add
+def set_code_review_env(config, jobs):
+    """
+    Add a CODE_REVIEW environment variable when running in code-review bot mode
+    """
+    is_code_review = config.params["target_tasks_method"] == "codereview"
+
+    for job in jobs:
+        attrs = job.get("attributes", {})
+        if is_code_review and attrs.get("code-review") is True:
+            env = job["worker"].setdefault("env", {})
+            env["CODE_REVIEW"] = "1"
+
+        yield job
+
+
+@transforms.add
+def set_base_revision_in_tgdiff(config, jobs):
+    # Don't attempt to download 'json-automation' locally as the revision may
+    # not exist in the repository.
+    if not os.environ.get("MOZ_AUTOMATION") or taskgraph.fast:
+        yield from jobs
+        return
+
+    data = get_json_automationrelevance(
+        config.params["head_repository"], config.params["head_rev"]
+    )
+    for job in jobs:
+        if job["name"] != "taskgraph-diff":
+            yield job
+            continue
+
+        job["run"]["command-context"] = {
+            "base_rev": data["changesets"][0]["parents"][0]
+        }
+        yield job
+
+
+@transforms.add
+def set_worker_exit_code(config, jobs):
+    for job in jobs:
+        worker = job["worker"]
+        worker.setdefault("retry-exit-status", [])
+        if 137 not in worker["retry-exit-status"]:
+            worker["retry-exit-status"].append(137)
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/spidermonkey.py b/taskcluster/gecko_taskgraph/transforms/spidermonkey.py
new file mode 100644
index 0000000000..8e652f1668
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/spidermonkey.py
@@ -0,0 +1,21 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+import copy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def handle_keyed_by(config, jobs):
+    """Resolve fields that can be keyed by platform, etc."""
+    fields = ["fetches.toolchain"]
+    for job in jobs:
+        job = copy.deepcopy(job)  # don't overwrite dict values here
+        for field in fields:
+            resolve_keyed_by(item=job, field=field, item_name=job["name"])
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/split_by_locale.py b/taskcluster/gecko_taskgraph/transforms/split_by_locale.py
new file mode 100644
index 0000000000..ae68ab5051
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/split_by_locale.py
@@ -0,0 +1,79 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+This transform splits the jobs it receives into per-locale tasks. Locales are
+provided by the `locales-file`.
+"""
+
+from copy import deepcopy
+from pprint import pprint
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema
+from voluptuous import Extra, Optional, Required
+
+from gecko_taskgraph.transforms.l10n import parse_locales_file
+
+transforms = TransformSequence()
+
+split_by_locale_schema = Schema(
+    {
+        # The file to pull locale information from. This should be a json file
+        # such as browser/locales/l10n-changesets.json.
+        Required("locales-file"): str,
+        # The platform name in the form used by the locales files. Defaults to
+        # attributes.build_platform if not provided.
+        Optional("locale-file-platform"): str,
+        # A list of properties elsewhere in the job that need to have the locale
+        # name substituted into them. The referenced properties may be strings
+        # or lists. In the case of the latter, all list values will have
+        # substitutions performed.
+        Optional("properties-with-locale"): [str],
+        Extra: object,
+    }
+)
+
+
+transforms.add_validate(split_by_locale_schema)
+
+
+@transforms.add
+def add_command(config, jobs):
+    for job in jobs:
+        locales_file = job.pop("locales-file")
+        properties_with_locale = job.pop("properties-with-locale")
+        build_platform = job.pop(
+            "locale-file-platform", job["attributes"]["build_platform"]
+        )
+
+        for locale in parse_locales_file(locales_file, build_platform):
+            locale_job = deepcopy(job)
+            locale_job["attributes"]["locale"] = locale
+            for prop in properties_with_locale:
+                container, subfield = locale_job, prop
+                while "." in subfield:
+                    f, subfield = subfield.split(".", 1)
+                    if f not in container:
+                        raise Exception(
+                            f"Unable to find property {prop} to perform locale substitution on. Job is:\n{pprint(job)}"
+                        )
+                    container = container[f]
+                    if not isinstance(container, dict):
+                        raise Exception(
+                            f"{container} is not a dict, cannot perform locale substitution. Job is:\n{pprint(job)}"
+                        )
+
+                if isinstance(container[subfield], str):
+                    container[subfield] = container[subfield].format(locale=locale)
+                elif isinstance(container[subfield], list):
+                    for i in range(len(container[subfield])):
+                        container[subfield][i] = container[subfield][i].format(
+                            locale=locale
+                        )
+                else:
+                    raise Exception(
+                        f"Don't know how to subtitute locale for value of type: {type(container[subfield])}; value is: {container[subfield]}"
+                    )
+
+            yield locale_job
diff --git a/taskcluster/gecko_taskgraph/transforms/startup_test.py b/taskcluster/gecko_taskgraph/transforms/startup_test.py
new file mode 100644
index 0000000000..2660ef6e93
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/startup_test.py
@@ -0,0 +1,40 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_command(config, jobs):
+    for job in jobs:
+        extra_config = job.pop("extra-config")
+        upstream_kind = extra_config["upstream_kind"]
+        upstream_artifact = extra_config["upstream_artifact"]
+        binary = extra_config["binary"]
+        package_to_test = "<{}/public/build/{}>".format(
+            upstream_kind, upstream_artifact
+        )
+
+        if job["attributes"]["build_platform"].startswith("linux"):
+            job["run"]["command"] = {
+                "artifact-reference": ". $HOME/scripts/xvfb.sh && start_xvfb '1600x1200x24' 0 && "
+                + "python3 ./mach python testing/mozharness/scripts/does_it_crash.py "
+                + "--run-for 30 --thing-url "
+                + package_to_test
+                + " --thing-to-run "
+                + binary
+            }
+        else:
+            job["run"]["mach"] = {
+                "artifact-reference": "python testing/mozharness/scripts/does_it_crash.py "
+                + "--run-for 30 --thing-url "
+                + package_to_test
+                + " --thing-to-run "
+                + binary
+            }
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/strip_dependent_task.py b/taskcluster/gecko_taskgraph/transforms/strip_dependent_task.py
new file mode 100644
index 0000000000..4e1ec8783a
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/strip_dependent_task.py
@@ -0,0 +1,17 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+FIXME
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def strip_dependent_task(config, jobs):
+    for job in jobs:
+        del job["primary-dependency"]
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/task.py b/taskcluster/gecko_taskgraph/transforms/task.py
new file mode 100644
index 0000000000..e823e96b21
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/task.py
@@ -0,0 +1,2266 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+These transformations take a task description and turn it into a TaskCluster
+task definition (along with attributes, label, etc.).  The input to these
+transformations is generic to any kind of task, but abstracts away some of the
+complexities of worker implementations, scopes, and treeherder annotations.
+"""
+
+
+import datetime
+import hashlib
+import os
+import re
+import time
+
+import attr
+from mozbuild.util import memoize
+from taskcluster.utils import fromNow
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.keyed_by import evaluate_keyed_by
+from taskgraph.util.schema import (
+    Schema,
+    optionally_keyed_by,
+    resolve_keyed_by,
+    taskref_or_string,
+    validate_schema,
+)
+from taskgraph.util.treeherder import split_symbol
+from voluptuous import All, Any, Extra, Match, NotIn, Optional, Required
+
+from gecko_taskgraph import GECKO, MAX_DEPENDENCIES
+from gecko_taskgraph.optimize.schema import OptimizationSchema
+from gecko_taskgraph.transforms.job.common import get_expiration
+from gecko_taskgraph.util import docker as dockerutil
+from gecko_taskgraph.util.attributes import TRUNK_PROJECTS, is_try, release_level
+from gecko_taskgraph.util.copy_task import copy_task
+from gecko_taskgraph.util.hash import hash_path
+from gecko_taskgraph.util.partners import get_partners_to_be_published
+from gecko_taskgraph.util.scriptworker import BALROG_ACTIONS, get_release_config
+from gecko_taskgraph.util.signed_artifacts import get_signed_artifacts
+from gecko_taskgraph.util.workertypes import get_worker_type, worker_type_implementation
+
+RUN_TASK = os.path.join(GECKO, "taskcluster", "scripts", "run-task")
+
+SCCACHE_GCS_PROJECT = "sccache-3"
+
+
+@memoize
+def _run_task_suffix():
+    """String to append to cache names under control of run-task."""
+    return hash_path(RUN_TASK)[0:20]
+
+
+def _compute_geckoview_version(app_version, moz_build_date):
+    """Geckoview version string that matches geckoview gradle configuration"""
+    # Must be synchronized with /mobile/android/geckoview/build.gradle computeVersionCode(...)
+    version_without_milestone = re.sub(r"a[0-9]", "", app_version, 1)
+    parts = version_without_milestone.split(".")
+    return f"{parts[0]}.{parts[1]}.{moz_build_date}"
+
+
+# A task description is a general description of a TaskCluster task
+task_description_schema = Schema(
+    {
+        # the label for this task
+        Required("label"): str,
+        # description of the task (for metadata)
+        Required("description"): str,
+        # attributes for this task
+        Optional("attributes"): {str: object},
+        # relative path (from config.path) to the file task was defined in
+        Optional("job-from"): str,
+        # dependencies of this task, keyed by name; these are passed through
+        # verbatim and subject to the interpretation of the Task's get_dependencies
+        # method.
+        Optional("dependencies"): {
+            All(
+                str,
+                NotIn(
+                    ["self", "decision"],
+                    "Can't use 'self` or 'decision' as depdency names.",
+                ),
+            ): object,
+        },
+        # Soft dependencies of this task, as a list of tasks labels
+        Optional("soft-dependencies"): [str],
+        # Dependencies that must be scheduled in order for this task to run.
+        Optional("if-dependencies"): [str],
+        Optional("requires"): Any("all-completed", "all-resolved"),
+        # expiration and deadline times, relative to task creation, with units
+        # (e.g., "14 days").  Defaults are set based on the project.
+        Optional("expires-after"): str,
+        Optional("deadline-after"): str,
+        Optional("expiration-policy"): str,
+        # custom routes for this task; the default treeherder routes will be added
+        # automatically
+        Optional("routes"): [str],
+        # custom scopes for this task; any scopes required for the worker will be
+        # added automatically. The following parameters will be substituted in each
+        # scope:
+        #  {level} -- the scm level of this push
+        #  {project} -- the project of this push
+        Optional("scopes"): [str],
+        # Tags
+        Optional("tags"): {str: str},
+        # custom "task.extra" content
+        Optional("extra"): {str: object},
+        # treeherder-related information; see
+        # https://firefox-ci-tc.services.mozilla.com/schemas/taskcluster-treeherder/v1/task-treeherder-config.json
+        # If not specified, no treeherder extra information or routes will be
+        # added to the task
+        Optional("treeherder"): {
+            # either a bare symbol, or "grp(sym)".
+            "symbol": str,
+            # the job kind
+            "kind": Any("build", "test", "other"),
+            # tier for this task
+            "tier": int,
+            # task platform, in the form platform/collection, used to set
+            # treeherder.machine.platform and treeherder.collection or
+            # treeherder.labels
+            "platform": Match("^[A-Za-z0-9_-]{1,50}/[A-Za-z0-9_-]{1,50}$"),
+        },
+        # information for indexing this build so its artifacts can be discovered;
+        # if omitted, the build will not be indexed.
+        Optional("index"): {
+            # the name of the product this build produces
+            "product": str,
+            # the names to use for this job in the TaskCluster index
+            "job-name": str,
+            # Type of gecko v2 index to use
+            "type": Any(
+                "generic",
+                "l10n",
+                "shippable",
+                "shippable-l10n",
+                "android-shippable",
+                "android-shippable-with-multi-l10n",
+                "shippable-with-multi-l10n",
+            ),
+            # The rank that the task will receive in the TaskCluster
+            # index.  A newly completed task supercedes the currently
+            # indexed task iff it has a higher rank.  If unspecified,
+            # 'by-tier' behavior will be used.
+            "rank": Any(
+                # Rank is equal the timestamp of the build_date for tier-1
+                # tasks, and zero for non-tier-1.  This sorts tier-{2,3}
+                # builds below tier-1 in the index.
+                "by-tier",
+                # Rank is given as an integer constant (e.g. zero to make
+                # sure a task is last in the index).
+                int,
+                # Rank is equal to the timestamp of the build_date.  This
+                # option can be used to override the 'by-tier' behavior
+                # for non-tier-1 tasks.
+                "build_date",
+            ),
+        },
+        # The `run_on_projects` attribute, defaulting to "all".  This dictates the
+        # projects on which this task should be included in the target task set.
+        # See the attributes documentation for details.
+        Optional("run-on-projects"): optionally_keyed_by("build-platform", [str]),
+        # Like `run_on_projects`, `run-on-hg-branches` defaults to "all".
+        Optional("run-on-hg-branches"): optionally_keyed_by("project", [str]),
+        # The `shipping_phase` attribute, defaulting to None. This specifies the
+        # release promotion phase that this task belongs to.
+        Required("shipping-phase"): Any(
+            None,
+            "build",
+            "promote",
+            "push",
+            "ship",
+        ),
+        # The `shipping_product` attribute, defaulting to None. This specifies the
+        # release promotion product that this task belongs to.
+        Required("shipping-product"): Any(None, str),
+        # The `always-target` attribute will cause the task to be included in the
+        # target_task_graph regardless of filtering. Tasks included in this manner
+        # will be candidates for optimization even when `optimize_target_tasks` is
+        # False, unless the task was also explicitly chosen by the target_tasks
+        # method.
+        Required("always-target"): bool,
+        # Optimization to perform on this task during the optimization phase.
+        # Optimizations are defined in taskcluster/gecko_taskgraph/optimize.py.
+        Required("optimization"): OptimizationSchema,
+        # the provisioner-id/worker-type for the task.  The following parameters will
+        # be substituted in this string:
+        #  {level} -- the scm level of this push
+        "worker-type": str,
+        # Whether the job should use sccache compiler caching.
+        Required("use-sccache"): bool,
+        # information specific to the worker implementation that will run this task
+        Optional("worker"): {
+            Required("implementation"): str,
+            Extra: object,
+        },
+        # Override the default priority for the project
+        Optional("priority"): str,
+    }
+)
+
+TC_TREEHERDER_SCHEMA_URL = (
+    "https://github.com/taskcluster/taskcluster-treeherder/"
+    "blob/master/schemas/task-treeherder-config.yml"
+)
+
+
+UNKNOWN_GROUP_NAME = (
+    "Treeherder group {} (from {}) has no name; " "add it to taskcluster/ci/config.yml"
+)
+
+V2_ROUTE_TEMPLATES = [
+    "index.{trust-domain}.v2.{project}.latest.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.pushdate.{build_date_long}.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.pushdate.{build_date}.latest.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.pushlog-id.{pushlog_id}.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.revision.{branch_rev}.{product}.{job-name}",
+]
+
+# {central, inbound, autoland} write to a "trunk" index prefix. This facilitates
+# walking of tasks with similar configurations.
+V2_TRUNK_ROUTE_TEMPLATES = [
+    "index.{trust-domain}.v2.trunk.revision.{branch_rev}.{product}.{job-name}",
+]
+
+V2_SHIPPABLE_TEMPLATES = [
+    "index.{trust-domain}.v2.{project}.shippable.latest.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.shippable.{build_date}.revision.{branch_rev}.{product}.{job-name}",  # noqa - too long
+    "index.{trust-domain}.v2.{project}.shippable.{build_date}.latest.{product}.{job-name}",
+    "index.{trust-domain}.v2.{project}.shippable.revision.{branch_rev}.{product}.{job-name}",
+]
+
+V2_SHIPPABLE_L10N_TEMPLATES = [
+    "index.{trust-domain}.v2.{project}.shippable.latest.{product}-l10n.{job-name}.{locale}",
+    "index.{trust-domain}.v2.{project}.shippable.{build_date}.revision.{branch_rev}.{product}-l10n.{job-name}.{locale}",  # noqa - too long
+    "index.{trust-domain}.v2.{project}.shippable.{build_date}.latest.{product}-l10n.{job-name}.{locale}",  # noqa - too long
+    "index.{trust-domain}.v2.{project}.shippable.revision.{branch_rev}.{product}-l10n.{job-name}.{locale}",  # noqa - too long
+]
+
+V2_L10N_TEMPLATES = [
+    "index.{trust-domain}.v2.{project}.revision.{branch_rev}.{product}-l10n.{job-name}.{locale}",
+    "index.{trust-domain}.v2.{project}.pushdate.{build_date_long}.{product}-l10n.{job-name}.{locale}",  # noqa - too long
+    "index.{trust-domain}.v2.{project}.pushlog-id.{pushlog_id}.{product}-l10n.{job-name}.{locale}",
+    "index.{trust-domain}.v2.{project}.latest.{product}-l10n.{job-name}.{locale}",
+]
+
+# This index is specifically for builds that include geckoview releases,
+# so we can hard-code the project to "geckoview"
+V2_GECKOVIEW_RELEASE = "index.{trust-domain}.v2.{project}.geckoview-version.{geckoview-version}.{product}.{job-name}"  # noqa - too long
+
+# the roots of the treeherder routes
+TREEHERDER_ROUTE_ROOT = "tc-treeherder"
+
+
+def get_branch_rev(config):
+    return config.params[
+        "{}head_rev".format(config.graph_config["project-repo-param-prefix"])
+    ]
+
+
+def get_branch_repo(config):
+    return config.params[
+        "{}head_repository".format(
+            config.graph_config["project-repo-param-prefix"],
+        )
+    ]
+
+
+@memoize
+def get_default_priority(graph_config, project):
+    return evaluate_keyed_by(
+        graph_config["task-priority"], "Graph Config", {"project": project}
+    )
+
+
+# define a collection of payload builders, depending on the worker implementation
+payload_builders = {}
+
+
+@attr.s(frozen=True)
+class PayloadBuilder:
+    schema = attr.ib(type=Schema)
+    builder = attr.ib()
+
+
+def payload_builder(name, schema):
+    schema = Schema({Required("implementation"): name, Optional("os"): str}).extend(
+        schema
+    )
+
+    def wrap(func):
+        payload_builders[name] = PayloadBuilder(schema, func)
+        return func
+
+    return wrap
+
+
+# define a collection of index builders, depending on the type implementation
+index_builders = {}
+
+
+def index_builder(name):
+    def wrap(func):
+        index_builders[name] = func
+        return func
+
+    return wrap
+
+
+UNSUPPORTED_INDEX_PRODUCT_ERROR = """\
+The gecko-v2 product {product} is not in the list of configured products in
+`taskcluster/ci/config.yml'.
+"""
+
+
+def verify_index(config, index):
+    product = index["product"]
+    if product not in config.graph_config["index"]["products"]:
+        raise Exception(UNSUPPORTED_INDEX_PRODUCT_ERROR.format(product=product))
+
+
+@payload_builder(
+    "docker-worker",
+    schema={
+        Required("os"): "linux",
+        # For tasks that will run in docker-worker, this is the
+        # name of the docker image or in-tree docker image to run the task in.  If
+        # in-tree, then a dependency will be created automatically.  This is
+        # generally `desktop-test`, or an image that acts an awful lot like it.
+        Required("docker-image"): Any(
+            # a raw Docker image path (repo/image:tag)
+            str,
+            # an in-tree generated docker image (from `taskcluster/docker/<name>`)
+            {"in-tree": str},
+            # an indexed docker image
+            {"indexed": str},
+        ),
+        # worker features that should be enabled
+        Required("chain-of-trust"): bool,
+        Required("taskcluster-proxy"): bool,
+        Required("allow-ptrace"): bool,
+        Required("loopback-video"): bool,
+        Required("loopback-audio"): bool,
+        Required("docker-in-docker"): bool,  # (aka 'dind')
+        Required("privileged"): bool,
+        # Paths to Docker volumes.
+        #
+        # For in-tree Docker images, volumes can be parsed from Dockerfile.
+        # This only works for the Dockerfile itself: if a volume is defined in
+        # a base image, it will need to be declared here. Out-of-tree Docker
+        # images will also require explicit volume annotation.
+        #
+        # Caches are often mounted to the same path as Docker volumes. In this
+        # case, they take precedence over a Docker volume. But a volume still
+        # needs to be declared for the path.
+        Optional("volumes"): [str],
+        Optional(
+            "required-volumes",
+            description=(
+                "Paths that are required to be volumes for performance reasons. "
+                "For in-tree images, these paths will be checked to verify that they "
+                "are defined as volumes."
+            ),
+        ): [str],
+        # caches to set up for the task
+        Optional("caches"): [
+            {
+                # only one type is supported by any of the workers right now
+                "type": "persistent",
+                # name of the cache, allowing re-use by subsequent tasks naming the
+                # same cache
+                "name": str,
+                # location in the task image where the cache will be mounted
+                "mount-point": str,
+                # Whether the cache is not used in untrusted environments
+                # (like the Try repo).
+                Optional("skip-untrusted"): bool,
+            }
+        ],
+        # artifacts to extract from the task image after completion
+        Optional("artifacts"): [
+            {
+                # type of artifact -- simple file, or recursive directory
+                "type": Any("file", "directory"),
+                # task image path from which to read artifact
+                "path": str,
+                # name of the produced artifact (root of the names for
+                # type=directory)
+                "name": str,
+                "expires-after": str,
+            }
+        ],
+        # environment variables
+        Required("env"): {str: taskref_or_string},
+        # the command to run; if not given, docker-worker will default to the
+        # command in the docker image
+        Optional("command"): [taskref_or_string],
+        # the maximum time to run, in seconds
+        Required("max-run-time"): int,
+        # the exit status code(s) that indicates the task should be retried
+        Optional("retry-exit-status"): [int],
+        # the exit status code(s) that indicates the caches used by the task
+        # should be purged
+        Optional("purge-caches-exit-status"): [int],
+        # Whether any artifacts are assigned to this worker
+        Optional("skip-artifacts"): bool,
+    },
+)
+def build_docker_worker_payload(config, task, task_def):
+    worker = task["worker"]
+    level = int(config.params["level"])
+
+    image = worker["docker-image"]
+    if isinstance(image, dict):
+        if "in-tree" in image:
+            name = image["in-tree"]
+            docker_image_task = "docker-image-" + image["in-tree"]
+            task.setdefault("dependencies", {})["docker-image"] = docker_image_task
+
+            image = {
+                "path": "public/image.tar.zst",
+                "taskId": {"task-reference": "<docker-image>"},
+                "type": "task-image",
+            }
+
+            # Find VOLUME in Dockerfile.
+            volumes = dockerutil.parse_volumes(name)
+            for v in sorted(volumes):
+                if v in worker["volumes"]:
+                    raise Exception(
+                        "volume %s already defined; "
+                        "if it is defined in a Dockerfile, "
+                        "it does not need to be specified in the "
+                        "worker definition" % v
+                    )
+
+                worker["volumes"].append(v)
+
+        elif "indexed" in image:
+            image = {
+                "path": "public/image.tar.zst",
+                "namespace": image["indexed"],
+                "type": "indexed-image",
+            }
+        else:
+            raise Exception("unknown docker image type")
+
+    features = {}
+
+    if worker.get("taskcluster-proxy"):
+        features["taskclusterProxy"] = True
+
+    if worker.get("allow-ptrace"):
+        features["allowPtrace"] = True
+        task_def["scopes"].append("docker-worker:feature:allowPtrace")
+
+    if worker.get("chain-of-trust"):
+        features["chainOfTrust"] = True
+
+    if worker.get("docker-in-docker"):
+        features["dind"] = True
+
+    # Never enable sccache on the toolchains repo, as there is no benefit from it
+    # because each push uses a different compiler.
+    if task.get("use-sccache") and config.params["project"] != "toolchains":
+        features["taskclusterProxy"] = True
+        task_def["scopes"].append(
+            "assume:project:taskcluster:{trust_domain}:level-{level}-sccache-buckets".format(
+                trust_domain=config.graph_config["trust-domain"],
+                level=config.params["level"],
+            )
+        )
+        worker["env"]["USE_SCCACHE"] = "1"
+        worker["env"]["SCCACHE_GCS_PROJECT"] = SCCACHE_GCS_PROJECT
+        # Disable sccache idle shutdown.
+        worker["env"]["SCCACHE_IDLE_TIMEOUT"] = "0"
+    else:
+        worker["env"]["SCCACHE_DISABLE"] = "1"
+
+    capabilities = {}
+
+    for lo in "audio", "video":
+        if worker.get("loopback-" + lo):
+            capitalized = "loopback" + lo.capitalize()
+            devices = capabilities.setdefault("devices", {})
+            devices[capitalized] = True
+            task_def["scopes"].append("docker-worker:capability:device:" + capitalized)
+
+    if worker.get("privileged"):
+        capabilities["privileged"] = True
+        task_def["scopes"].append("docker-worker:capability:privileged")
+
+    task_def["payload"] = payload = {
+        "image": image,
+        "env": worker["env"],
+    }
+    if "command" in worker:
+        payload["command"] = worker["command"]
+
+    if "max-run-time" in worker:
+        payload["maxRunTime"] = worker["max-run-time"]
+
+    run_task = payload.get("command", [""])[0].endswith("run-task")
+
+    # run-task exits EXIT_PURGE_CACHES if there is a problem with caches.
+    # Automatically retry the tasks and purge caches if we see this exit
+    # code.
+    # TODO move this closer to code adding run-task once bug 1469697 is
+    # addressed.
+    if run_task:
+        worker.setdefault("retry-exit-status", []).append(72)
+        worker.setdefault("purge-caches-exit-status", []).append(72)
+
+    payload["onExitStatus"] = {}
+    if "retry-exit-status" in worker:
+        payload["onExitStatus"]["retry"] = worker["retry-exit-status"]
+    if "purge-caches-exit-status" in worker:
+        payload["onExitStatus"]["purgeCaches"] = worker["purge-caches-exit-status"]
+
+    if "artifacts" in worker:
+        artifacts = {}
+        expires_policy = get_expiration(
+            config, task.get("expiration-policy", "default")
+        )
+        now = datetime.datetime.utcnow()
+        task_exp = task_def["expires"]["relative-datestamp"]
+        task_exp_from_now = fromNow(task_exp)
+        for artifact in worker["artifacts"]:
+            art_exp = artifact.get("expires-after", expires_policy)
+            expires = art_exp if fromNow(art_exp, now) < task_exp_from_now else task_exp
+            artifacts[artifact["name"]] = {
+                "path": artifact["path"],
+                "type": artifact["type"],
+                "expires": {"relative-datestamp": expires},
+            }
+        payload["artifacts"] = artifacts
+
+    if isinstance(worker.get("docker-image"), str):
+        out_of_tree_image = worker["docker-image"]
+    else:
+        out_of_tree_image = None
+        image = worker.get("docker-image", {}).get("in-tree")
+
+    if "caches" in worker:
+        caches = {}
+
+        # run-task knows how to validate caches.
+        #
+        # To help ensure new run-task features and bug fixes don't interfere
+        # with existing caches, we seed the hash of run-task into cache names.
+        # So, any time run-task changes, we should get a fresh set of caches.
+        # This means run-task can make changes to cache interaction at any time
+        # without regards for backwards or future compatibility.
+        #
+        # But this mechanism only works for in-tree Docker images that are built
+        # with the current run-task! For out-of-tree Docker images, we have no
+        # way of knowing their content of run-task. So, in addition to varying
+        # cache names by the contents of run-task, we also take the Docker image
+        # name into consideration. This means that different Docker images will
+        # never share the same cache. This is a bit unfortunate. But it is the
+        # safest thing to do. Fortunately, most images are defined in-tree.
+        #
+        # For out-of-tree Docker images, we don't strictly need to incorporate
+        # the run-task content into the cache name. However, doing so preserves
+        # the mechanism whereby changing run-task results in new caches
+        # everywhere.
+
+        # As an additional mechanism to force the use of different caches, the
+        # string literal in the variable below can be changed. This is
+        # preferred to changing run-task because it doesn't require images
+        # to be rebuilt.
+        cache_version = "v3"
+
+        if run_task:
+            suffix = f"{cache_version}-{_run_task_suffix()}"
+
+            if out_of_tree_image:
+                name_hash = hashlib.sha256(
+                    out_of_tree_image.encode("utf-8")
+                ).hexdigest()
+                suffix += name_hash[0:12]
+
+        else:
+            suffix = cache_version
+
+        skip_untrusted = is_try(config.params) or level == 1
+
+        for cache in worker["caches"]:
+            # Some caches aren't enabled in environments where we can't
+            # guarantee certain behavior. Filter those out.
+            if cache.get("skip-untrusted") and skip_untrusted:
+                continue
+
+            name = "{trust_domain}-level-{level}-{name}-{suffix}".format(
+                trust_domain=config.graph_config["trust-domain"],
+                level=config.params["level"],
+                name=cache["name"],
+                suffix=suffix,
+            )
+
+            caches[name] = cache["mount-point"]
+            task_def["scopes"].append("docker-worker:cache:%s" % name)
+
+        # Assertion: only run-task is interested in this.
+        if run_task:
+            payload["env"]["TASKCLUSTER_CACHES"] = ";".join(sorted(caches.values()))
+
+        payload["cache"] = caches
+
+    # And send down volumes information to run-task as well.
+    if run_task and worker.get("volumes"):
+        payload["env"]["TASKCLUSTER_VOLUMES"] = ";".join(sorted(worker["volumes"]))
+
+    if payload.get("cache") and skip_untrusted:
+        payload["env"]["TASKCLUSTER_UNTRUSTED_CACHES"] = "1"
+
+    if features:
+        payload["features"] = features
+    if capabilities:
+        payload["capabilities"] = capabilities
+
+    check_caches_are_volumes(task)
+    check_required_volumes(task)
+
+
+@payload_builder(
+    "generic-worker",
+    schema={
+        Required("os"): Any("windows", "macosx", "linux", "linux-bitbar"),
+        # see http://schemas.taskcluster.net/generic-worker/v1/payload.json
+        # and https://docs.taskcluster.net/reference/workers/generic-worker/payload
+        # command is a list of commands to run, sequentially
+        # on Windows, each command is a string, on OS X and Linux, each command is
+        # a string array
+        Required("command"): Any(
+            [taskref_or_string], [[taskref_or_string]]  # Windows  # Linux / OS X
+        ),
+        # artifacts to extract from the task image after completion; note that artifacts
+        # for the generic worker cannot have names
+        Optional("artifacts"): [
+            {
+                # type of artifact -- simple file, or recursive directory
+                "type": Any("file", "directory"),
+                # filesystem path from which to read artifact
+                "path": str,
+                # if not specified, path is used for artifact name
+                Optional("name"): str,
+                "expires-after": str,
+            }
+        ],
+        # Directories and/or files to be mounted.
+        # The actual allowed combinations are stricter than the model below,
+        # but this provides a simple starting point.
+        # See https://docs.taskcluster.net/reference/workers/generic-worker/payload
+        Optional("mounts"): [
+            {
+                # A unique name for the cache volume, implies writable cache directory
+                # (otherwise mount is a read-only file or directory).
+                Optional("cache-name"): str,
+                # Optional content for pre-loading cache, or mandatory content for
+                # read-only file or directory. Pre-loaded content can come from either
+                # a task artifact or from a URL.
+                Optional("content"): {
+                    # *** Either (artifact and task-id) or url must be specified. ***
+                    # Artifact name that contains the content.
+                    Optional("artifact"): str,
+                    # Task ID that has the artifact that contains the content.
+                    Optional("task-id"): taskref_or_string,
+                    # URL that supplies the content in response to an unauthenticated
+                    # GET request.
+                    Optional("url"): str,
+                },
+                # *** Either file or directory must be specified. ***
+                # If mounting a cache or read-only directory, the filesystem location of
+                # the directory should be specified as a relative path to the task
+                # directory here.
+                Optional("directory"): str,
+                # If mounting a file, specify the relative path within the task
+                # directory to mount the file (the file will be read only).
+                Optional("file"): str,
+                # Required if and only if `content` is specified and mounting a
+                # directory (not a file). This should be the archive format of the
+                # content (either pre-loaded cache or read-only directory).
+                Optional("format"): Any("rar", "tar.bz2", "tar.gz", "zip"),
+            }
+        ],
+        # environment variables
+        Required("env"): {str: taskref_or_string},
+        # the maximum time to run, in seconds
+        Required("max-run-time"): int,
+        # os user groups for test task workers
+        Optional("os-groups"): [str],
+        # feature for test task to run as administarotr
+        Optional("run-as-administrator"): bool,
+        # optional features
+        Required("chain-of-trust"): bool,
+        Optional("taskcluster-proxy"): bool,
+        # the exit status code(s) that indicates the task should be retried
+        Optional("retry-exit-status"): [int],
+        # Wether any artifacts are assigned to this worker
+        Optional("skip-artifacts"): bool,
+    },
+)
+def build_generic_worker_payload(config, task, task_def):
+    worker = task["worker"]
+    features = {}
+
+    task_def["payload"] = {
+        "command": worker["command"],
+        "maxRunTime": worker["max-run-time"],
+    }
+
+    if worker["os"] == "windows":
+        task_def["payload"]["onExitStatus"] = {
+            "retry": [
+                # These codes (on windows) indicate a process interruption,
+                # rather than a task run failure. See bug 1544403.
+                1073807364,  # process force-killed due to system shutdown
+                3221225786,  # sigint (any interrupt)
+            ]
+        }
+    if "retry-exit-status" in worker:
+        task_def["payload"].setdefault("onExitStatus", {}).setdefault(
+            "retry", []
+        ).extend(worker["retry-exit-status"])
+    if worker["os"] == "linux-bitbar":
+        task_def["payload"].setdefault("onExitStatus", {}).setdefault("retry", [])
+        # exit code 4 is used to indicate an intermittent android device error
+        if 4 not in task_def["payload"]["onExitStatus"]["retry"]:
+            task_def["payload"]["onExitStatus"]["retry"].extend([4])
+
+    env = worker.get("env", {})
+
+    # Never enable sccache on the toolchains repo, as there is no benefit from it
+    # because each push uses a different compiler.
+    if task.get("use-sccache") and config.params["project"] != "toolchains":
+        features["taskclusterProxy"] = True
+        task_def["scopes"].append(
+            "assume:project:taskcluster:{trust_domain}:level-{level}-sccache-buckets".format(
+                trust_domain=config.graph_config["trust-domain"],
+                level=config.params["level"],
+            )
+        )
+        env["USE_SCCACHE"] = "1"
+        worker["env"]["SCCACHE_GCS_PROJECT"] = SCCACHE_GCS_PROJECT
+        # Disable sccache idle shutdown.
+        env["SCCACHE_IDLE_TIMEOUT"] = "0"
+    else:
+        env["SCCACHE_DISABLE"] = "1"
+
+    if env:
+        task_def["payload"]["env"] = env
+
+    artifacts = []
+
+    expires_policy = get_expiration(config, task.get("expiration-policy", "default"))
+    now = datetime.datetime.utcnow()
+    task_exp = task_def["expires"]["relative-datestamp"]
+    task_exp_from_now = fromNow(task_exp)
+    for artifact in worker.get("artifacts", []):
+        art_exp = artifact.get("expires-after", expires_policy)
+        task_exp = task_def["expires"]["relative-datestamp"]
+        expires = art_exp if fromNow(art_exp, now) < task_exp_from_now else task_exp
+        a = {
+            "path": artifact["path"],
+            "type": artifact["type"],
+            "expires": {"relative-datestamp": expires},
+        }
+        if "name" in artifact:
+            a["name"] = artifact["name"]
+        artifacts.append(a)
+
+    if artifacts:
+        task_def["payload"]["artifacts"] = artifacts
+
+    # Need to copy over mounts, but rename keys to respect naming convention
+    #   * 'cache-name' -> 'cacheName'
+    #   * 'task-id'    -> 'taskId'
+    # All other key names are already suitable, and don't need renaming.
+    mounts = copy_task(worker.get("mounts", []))
+    for mount in mounts:
+        if "cache-name" in mount:
+            mount["cacheName"] = "{trust_domain}-level-{level}-{name}".format(
+                trust_domain=config.graph_config["trust-domain"],
+                level=config.params["level"],
+                name=mount.pop("cache-name"),
+            )
+            task_def["scopes"].append(
+                "generic-worker:cache:{}".format(mount["cacheName"])
+            )
+        if "content" in mount:
+            if "task-id" in mount["content"]:
+                mount["content"]["taskId"] = mount["content"].pop("task-id")
+            if "artifact" in mount["content"]:
+                if not mount["content"]["artifact"].startswith("public/"):
+                    task_def["scopes"].append(
+                        "queue:get-artifact:{}".format(mount["content"]["artifact"])
+                    )
+
+    if mounts:
+        task_def["payload"]["mounts"] = mounts
+
+    if worker.get("os-groups"):
+        task_def["payload"]["osGroups"] = worker["os-groups"]
+        task_def["scopes"].extend(
+            [
+                "generic-worker:os-group:{}/{}".format(task["worker-type"], group)
+                for group in worker["os-groups"]
+            ]
+        )
+
+    if worker.get("chain-of-trust"):
+        features["chainOfTrust"] = True
+
+    if worker.get("taskcluster-proxy"):
+        features["taskclusterProxy"] = True
+
+    if worker.get("run-as-administrator", False):
+        features["runAsAdministrator"] = True
+        task_def["scopes"].append(
+            "generic-worker:run-as-administrator:{}".format(task["worker-type"]),
+        )
+
+    if features:
+        task_def["payload"]["features"] = features
+
+
+@payload_builder(
+    "scriptworker-signing",
+    schema={
+        # the maximum time to run, in seconds
+        Required("max-run-time"): int,
+        # list of artifact URLs for the artifacts that should be signed
+        Required("upstream-artifacts"): [
+            {
+                # taskId of the task with the artifact
+                Required("taskId"): taskref_or_string,
+                # type of signing task (for CoT)
+                Required("taskType"): str,
+                # Paths to the artifacts to sign
+                Required("paths"): [str],
+                # Signing formats to use on each of the paths
+                Required("formats"): [str],
+                Optional("singleFileGlobs"): [str],
+            }
+        ],
+        # behavior for mac iscript
+        Optional("mac-behavior"): Any(
+            "apple_notarization",
+            "mac_sign_and_pkg",
+            "mac_geckodriver",
+            "mac_notarize_geckodriver",
+            "mac_single_file",
+            "mac_notarize_single_file",
+        ),
+        Optional("entitlements-url"): str,
+        Optional("requirements-plist-url"): str,
+    },
+)
+def build_scriptworker_signing_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {
+        "maxRunTime": worker["max-run-time"],
+        "upstreamArtifacts": worker["upstream-artifacts"],
+    }
+    if worker.get("mac-behavior"):
+        task_def["payload"]["behavior"] = worker["mac-behavior"]
+        for attribute in ("entitlements-url", "requirements-plist-url"):
+            if worker.get(attribute):
+                task_def["payload"][attribute] = worker[attribute]
+
+    artifacts = set(task.setdefault("attributes", {}).get("release_artifacts", []))
+    for upstream_artifact in worker["upstream-artifacts"]:
+        for path in upstream_artifact["paths"]:
+            artifacts.update(
+                get_signed_artifacts(
+                    input=path,
+                    formats=upstream_artifact["formats"],
+                    behavior=worker.get("mac-behavior"),
+                )
+            )
+    task["attributes"]["release_artifacts"] = sorted(list(artifacts))
+
+
+@payload_builder(
+    "beetmover",
+    schema={
+        # the maximum time to run, in seconds
+        Required("max-run-time"): int,
+        # locale key, if this is a locale beetmover job
+        Optional("locale"): str,
+        Optional("partner-public"): bool,
+        Required("release-properties"): {
+            "app-name": str,
+            "app-version": str,
+            "branch": str,
+            "build-id": str,
+            "hash-type": str,
+            "platform": str,
+        },
+        # list of artifact URLs for the artifacts that should be beetmoved
+        Required("upstream-artifacts"): [
+            {
+                # taskId of the task with the artifact
+                Required("taskId"): taskref_or_string,
+                # type of signing task (for CoT)
+                Required("taskType"): str,
+                # Paths to the artifacts to sign
+                Required("paths"): [str],
+                # locale is used to map upload path and allow for duplicate simple names
+                Required("locale"): str,
+            }
+        ],
+        Optional("artifact-map"): object,
+    },
+)
+def build_beetmover_payload(config, task, task_def):
+    worker = task["worker"]
+    release_config = get_release_config(config)
+    release_properties = worker["release-properties"]
+
+    task_def["payload"] = {
+        "maxRunTime": worker["max-run-time"],
+        "releaseProperties": {
+            "appName": release_properties["app-name"],
+            "appVersion": release_properties["app-version"],
+            "branch": release_properties["branch"],
+            "buildid": release_properties["build-id"],
+            "hashType": release_properties["hash-type"],
+            "platform": release_properties["platform"],
+        },
+        "upload_date": config.params["build_date"],
+        "upstreamArtifacts": worker["upstream-artifacts"],
+    }
+    if worker.get("locale"):
+        task_def["payload"]["locale"] = worker["locale"]
+    if worker.get("artifact-map"):
+        task_def["payload"]["artifactMap"] = worker["artifact-map"]
+    if worker.get("partner-public"):
+        task_def["payload"]["is_partner_repack_public"] = worker["partner-public"]
+    if release_config:
+        task_def["payload"].update(release_config)
+
+
+@payload_builder(
+    "beetmover-push-to-release",
+    schema={
+        # the maximum time to run, in seconds
+        Required("max-run-time"): int,
+        Required("product"): str,
+    },
+)
+def build_beetmover_push_to_release_payload(config, task, task_def):
+    worker = task["worker"]
+    release_config = get_release_config(config)
+    partners = [f"{p}/{s}" for p, s, _ in get_partners_to_be_published(config)]
+
+    task_def["payload"] = {
+        "maxRunTime": worker["max-run-time"],
+        "product": worker["product"],
+        "version": release_config["version"],
+        "build_number": release_config["build_number"],
+        "partners": partners,
+    }
+
+
+@payload_builder(
+    "beetmover-import-from-gcs-to-artifact-registry",
+    schema={
+        Required("max-run-time"): int,
+        Required("gcs-sources"): [str],
+        Required("product"): str,
+    },
+)
+def build_import_from_gcs_to_artifact_registry_payload(config, task, task_def):
+    task_def["payload"] = {
+        "product": task["worker"]["product"],
+        "gcs_sources": task["worker"]["gcs-sources"],
+    }
+
+
+@payload_builder(
+    "beetmover-maven",
+    schema={
+        Required("max-run-time"): int,
+        Required("release-properties"): {
+            "app-name": str,
+            "app-version": str,
+            "branch": str,
+            "build-id": str,
+            "artifact-id": str,
+            "hash-type": str,
+            "platform": str,
+        },
+        Required("upstream-artifacts"): [
+            {
+                Required("taskId"): taskref_or_string,
+                Required("taskType"): str,
+                Required("paths"): [str],
+                Optional("zipExtract"): bool,
+            }
+        ],
+        Optional("artifact-map"): object,
+    },
+)
+def build_beetmover_maven_payload(config, task, task_def):
+    build_beetmover_payload(config, task, task_def)
+
+    task_def["payload"]["artifact_id"] = task["worker"]["release-properties"][
+        "artifact-id"
+    ]
+    if task["worker"].get("artifact-map"):
+        task_def["payload"]["artifactMap"] = task["worker"]["artifact-map"]
+
+    task_def["payload"]["version"] = _compute_geckoview_version(
+        task["worker"]["release-properties"]["app-version"],
+        task["worker"]["release-properties"]["build-id"],
+    )
+
+    del task_def["payload"]["releaseProperties"]["hashType"]
+    del task_def["payload"]["releaseProperties"]["platform"]
+
+
+@payload_builder(
+    "balrog",
+    schema={
+        Required("balrog-action"): Any(*BALROG_ACTIONS),
+        Optional("product"): str,
+        Optional("platforms"): [str],
+        Optional("release-eta"): str,
+        Optional("channel-names"): optionally_keyed_by("release-type", [str]),
+        Optional("require-mirrors"): bool,
+        Optional("publish-rules"): optionally_keyed_by(
+            "release-type", "release-level", [int]
+        ),
+        Optional("rules-to-update"): optionally_keyed_by(
+            "release-type", "release-level", [str]
+        ),
+        Optional("archive-domain"): optionally_keyed_by("release-level", str),
+        Optional("download-domain"): optionally_keyed_by("release-level", str),
+        Optional("blob-suffix"): str,
+        Optional("complete-mar-filename-pattern"): str,
+        Optional("complete-mar-bouncer-product-pattern"): str,
+        Optional("update-line"): object,
+        Optional("suffixes"): [str],
+        Optional("background-rate"): optionally_keyed_by(
+            "release-type", "beta-number", Any(int, None)
+        ),
+        Optional("force-fallback-mapping-update"): optionally_keyed_by(
+            "release-type", "beta-number", bool
+        ),
+        Optional("pin-channels"): optionally_keyed_by(
+            "release-type", "release-level", [str]
+        ),
+        # list of artifact URLs for the artifacts that should be beetmoved
+        Optional("upstream-artifacts"): [
+            {
+                # taskId of the task with the artifact
+                Required("taskId"): taskref_or_string,
+                # type of signing task (for CoT)
+                Required("taskType"): str,
+                # Paths to the artifacts to sign
+                Required("paths"): [str],
+            }
+        ],
+    },
+)
+def build_balrog_payload(config, task, task_def):
+    worker = task["worker"]
+    release_config = get_release_config(config)
+    beta_number = None
+    if "b" in release_config["version"]:
+        beta_number = release_config["version"].split("b")[-1]
+
+    task_def["payload"] = {
+        "behavior": worker["balrog-action"],
+    }
+
+    if (
+        worker["balrog-action"] == "submit-locale"
+        or worker["balrog-action"] == "v2-submit-locale"
+    ):
+        task_def["payload"].update(
+            {
+                "upstreamArtifacts": worker["upstream-artifacts"],
+                "suffixes": worker["suffixes"],
+            }
+        )
+    else:
+        for prop in (
+            "archive-domain",
+            "channel-names",
+            "download-domain",
+            "publish-rules",
+            "rules-to-update",
+            "background-rate",
+            "force-fallback-mapping-update",
+            "pin-channels",
+        ):
+            if prop in worker:
+                resolve_keyed_by(
+                    worker,
+                    prop,
+                    task["description"],
+                    **{
+                        "release-type": config.params["release_type"],
+                        "release-level": release_level(config.params["project"]),
+                        "beta-number": beta_number,
+                    },
+                )
+        task_def["payload"].update(
+            {
+                "build_number": release_config["build_number"],
+                "product": worker["product"],
+                "version": release_config["version"],
+            }
+        )
+        for prop in (
+            "blob-suffix",
+            "complete-mar-filename-pattern",
+            "complete-mar-bouncer-product-pattern",
+            "pin-channels",
+        ):
+            if prop in worker:
+                task_def["payload"][prop.replace("-", "_")] = worker[prop]
+        if (
+            worker["balrog-action"] == "submit-toplevel"
+            or worker["balrog-action"] == "v2-submit-toplevel"
+        ):
+            task_def["payload"].update(
+                {
+                    "app_version": release_config["appVersion"],
+                    "archive_domain": worker["archive-domain"],
+                    "channel_names": worker["channel-names"],
+                    "download_domain": worker["download-domain"],
+                    "partial_versions": release_config.get("partial_versions", ""),
+                    "platforms": worker["platforms"],
+                    "rules_to_update": worker["rules-to-update"],
+                    "require_mirrors": worker["require-mirrors"],
+                    "update_line": worker["update-line"],
+                }
+            )
+        else:  # schedule / ship
+            task_def["payload"].update(
+                {
+                    "publish_rules": worker["publish-rules"],
+                    "release_eta": worker.get(
+                        "release-eta", config.params.get("release_eta")
+                    )
+                    or "",
+                }
+            )
+            if worker.get("force-fallback-mapping-update"):
+                task_def["payload"]["force_fallback_mapping_update"] = worker[
+                    "force-fallback-mapping-update"
+                ]
+            if worker.get("background-rate"):
+                task_def["payload"]["background_rate"] = worker["background-rate"]
+
+
+@payload_builder(
+    "bouncer-aliases",
+    schema={
+        Required("entries"): object,
+    },
+)
+def build_bouncer_aliases_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {"aliases_entries": worker["entries"]}
+
+
+@payload_builder(
+    "bouncer-locations",
+    schema={
+        Required("implementation"): "bouncer-locations",
+        Required("bouncer-products"): [str],
+    },
+)
+def build_bouncer_locations_payload(config, task, task_def):
+    worker = task["worker"]
+    release_config = get_release_config(config)
+
+    task_def["payload"] = {
+        "bouncer_products": worker["bouncer-products"],
+        "version": release_config["version"],
+        "product": task["shipping-product"],
+    }
+
+
+@payload_builder(
+    "bouncer-submission",
+    schema={
+        Required("locales"): [str],
+        Required("entries"): object,
+    },
+)
+def build_bouncer_submission_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {
+        "locales": worker["locales"],
+        "submission_entries": worker["entries"],
+    }
+
+
+@payload_builder(
+    "push-flatpak",
+    schema={
+        Required("channel"): str,
+        Required("upstream-artifacts"): [
+            {
+                Required("taskId"): taskref_or_string,
+                Required("taskType"): str,
+                Required("paths"): [str],
+            }
+        ],
+    },
+)
+def build_push_flatpak_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {
+        "channel": worker["channel"],
+        "upstreamArtifacts": worker["upstream-artifacts"],
+    }
+
+
+@payload_builder(
+    "push-msix",
+    schema={
+        Required("channel"): str,
+        Optional("publish-mode"): str,
+        Required("upstream-artifacts"): [
+            {
+                Required("taskId"): taskref_or_string,
+                Required("taskType"): str,
+                Required("paths"): [str],
+            }
+        ],
+    },
+)
+def build_push_msix_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {
+        "channel": worker["channel"],
+        "upstreamArtifacts": worker["upstream-artifacts"],
+    }
+    if worker.get("publish-mode"):
+        task_def["payload"]["publishMode"] = worker["publish-mode"]
+
+
+@payload_builder(
+    "shipit-shipped",
+    schema={
+        Required("release-name"): str,
+    },
+)
+def build_ship_it_shipped_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {"release_name": worker["release-name"]}
+
+
+@payload_builder(
+    "shipit-maybe-release",
+    schema={
+        Required("phase"): str,
+    },
+)
+def build_ship_it_maybe_release_payload(config, task, task_def):
+    # expect branch name, including path
+    branch = config.params["head_repository"][len("https://hg.mozilla.org/") :]
+    # 'version' is e.g. '71.0b13' (app_version doesn't have beta number)
+    version = config.params["version"]
+
+    task_def["payload"] = {
+        "product": task["shipping-product"],
+        "branch": branch,
+        "phase": task["worker"]["phase"],
+        "version": version,
+        "cron_revision": config.params["head_rev"],
+    }
+
+
+@payload_builder(
+    "push-addons",
+    schema={
+        Required("channel"): Any("listed", "unlisted"),
+        Required("upstream-artifacts"): [
+            {
+                Required("taskId"): taskref_or_string,
+                Required("taskType"): str,
+                Required("paths"): [str],
+            }
+        ],
+    },
+)
+def build_push_addons_payload(config, task, task_def):
+    worker = task["worker"]
+
+    task_def["payload"] = {
+        "channel": worker["channel"],
+        "upstreamArtifacts": worker["upstream-artifacts"],
+    }
+
+
+@payload_builder(
+    "treescript",
+    schema={
+        Required("tags"): [Any("buildN", "release", None)],
+        Required("bump"): bool,
+        Optional("bump-files"): [str],
+        Optional("repo-param-prefix"): str,
+        Optional("dontbuild"): bool,
+        Optional("ignore-closed-tree"): bool,
+        Optional("force-dry-run"): bool,
+        Optional("push"): bool,
+        Optional("source-repo"): str,
+        Optional("ssh-user"): str,
+        Optional("l10n-bump-info"): {
+            Required("name"): str,
+            Required("path"): str,
+            Required("version-path"): str,
+            Optional("l10n-repo-url"): str,
+            Optional("ignore-config"): object,
+            Required("platform-configs"): [
+                {
+                    Required("platforms"): [str],
+                    Required("path"): str,
+                    Optional("format"): str,
+                }
+            ],
+        },
+        Optional("merge-info"): object,
+    },
+)
+def build_treescript_payload(config, task, task_def):
+    worker = task["worker"]
+    release_config = get_release_config(config)
+
+    task_def["payload"] = {"actions": []}
+    actions = task_def["payload"]["actions"]
+    if worker["tags"]:
+        tag_names = []
+        product = task["shipping-product"].upper()
+        version = release_config["version"].replace(".", "_")
+        buildnum = release_config["build_number"]
+        if "buildN" in worker["tags"]:
+            tag_names.extend(
+                [
+                    f"{product}_{version}_BUILD{buildnum}",
+                ]
+            )
+        if "release" in worker["tags"]:
+            tag_names.extend([f"{product}_{version}_RELEASE"])
+        tag_info = {
+            "tags": tag_names,
+            "revision": config.params[
+                "{}head_rev".format(worker.get("repo-param-prefix", ""))
+            ],
+        }
+        task_def["payload"]["tag_info"] = tag_info
+        actions.append("tag")
+
+    if worker["bump"]:
+        if not worker["bump-files"]:
+            raise Exception("Version Bump requested without bump-files")
+
+        bump_info = {}
+        bump_info["next_version"] = release_config["next_version"]
+        bump_info["files"] = worker["bump-files"]
+        task_def["payload"]["version_bump_info"] = bump_info
+        actions.append("version_bump")
+
+    if worker.get("l10n-bump-info"):
+        l10n_bump_info = {}
+        for k, v in worker["l10n-bump-info"].items():
+            l10n_bump_info[k.replace("-", "_")] = worker["l10n-bump-info"][k]
+        task_def["payload"]["l10n_bump_info"] = [l10n_bump_info]
+        actions.append("l10n_bump")
+
+    if worker.get("merge-info"):
+        merge_info = {
+            merge_param_name.replace("-", "_"): merge_param_value
+            for merge_param_name, merge_param_value in worker["merge-info"].items()
+            if merge_param_name != "version-files"
+        }
+        merge_info["version_files"] = [
+            {
+                file_param_name.replace("-", "_"): file_param_value
+                for file_param_name, file_param_value in file_entry.items()
+            }
+            for file_entry in worker["merge-info"]["version-files"]
+        ]
+        task_def["payload"]["merge_info"] = merge_info
+        actions.append("merge_day")
+
+    if worker["push"]:
+        actions.append("push")
+
+    if worker.get("force-dry-run"):
+        task_def["payload"]["dry_run"] = True
+
+    if worker.get("dontbuild"):
+        task_def["payload"]["dontbuild"] = True
+
+    if worker.get("ignore-closed-tree") is not None:
+        task_def["payload"]["ignore_closed_tree"] = worker["ignore-closed-tree"]
+
+    if worker.get("source-repo"):
+        task_def["payload"]["source_repo"] = worker["source-repo"]
+
+    if worker.get("ssh-user"):
+        task_def["payload"]["ssh_user"] = worker["ssh-user"]
+
+
+@payload_builder(
+    "invalid",
+    schema={
+        # an invalid task is one which should never actually be created; this is used in
+        # release automation on branches where the task just doesn't make sense
+        Extra: object,
+    },
+)
+def build_invalid_payload(config, task, task_def):
+    task_def["payload"] = "invalid task - should never be created"
+
+
+@payload_builder(
+    "always-optimized",
+    schema={
+        Extra: object,
+    },
+)
+@payload_builder("succeed", schema={})
+def build_dummy_payload(config, task, task_def):
+    task_def["payload"] = {}
+
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_implementation(config, tasks):
+    """
+    Set the worker implementation based on the worker-type alias.
+    """
+    for task in tasks:
+        if "implementation" in task["worker"]:
+            yield task
+            continue
+
+        impl, os = worker_type_implementation(
+            config.graph_config, config.params, task["worker-type"]
+        )
+
+        tags = task.setdefault("tags", {})
+        tags["worker-implementation"] = impl
+        if os:
+            tags["os"] = os
+
+        worker = task.setdefault("worker", {})
+        worker["implementation"] = impl
+        if os:
+            worker["os"] = os
+
+        yield task
+
+
+@transforms.add
+def set_defaults(config, tasks):
+    for task in tasks:
+        task.setdefault("shipping-phase", None)
+        task.setdefault("shipping-product", None)
+        task.setdefault("always-target", False)
+        task.setdefault("optimization", None)
+        task.setdefault("use-sccache", False)
+
+        worker = task["worker"]
+        if worker["implementation"] in ("docker-worker",):
+            worker.setdefault("chain-of-trust", False)
+            worker.setdefault("taskcluster-proxy", False)
+            worker.setdefault("allow-ptrace", True)
+            worker.setdefault("loopback-video", False)
+            worker.setdefault("loopback-audio", False)
+            worker.setdefault("docker-in-docker", False)
+            worker.setdefault("privileged", False)
+            worker.setdefault("volumes", [])
+            worker.setdefault("env", {})
+            if "caches" in worker:
+                for c in worker["caches"]:
+                    c.setdefault("skip-untrusted", False)
+        elif worker["implementation"] == "generic-worker":
+            worker.setdefault("env", {})
+            worker.setdefault("os-groups", [])
+            if worker["os-groups"] and worker["os"] != "windows":
+                raise Exception(
+                    "os-groups feature of generic-worker is only supported on "
+                    "Windows, not on {}".format(worker["os"])
+                )
+            worker.setdefault("chain-of-trust", False)
+        elif worker["implementation"] in (
+            "scriptworker-signing",
+            "beetmover",
+            "beetmover-push-to-release",
+            "beetmover-maven",
+            "beetmover-import-from-gcs-to-artifact-registry",
+        ):
+            worker.setdefault("max-run-time", 600)
+        elif worker["implementation"] == "push-apk":
+            worker.setdefault("commit", False)
+
+        yield task
+
+
+@transforms.add
+def setup_raptor(config, tasks):
+    """Add options that are specific to raptor jobs (identified by suite=raptor).
+
+    This variant uses a separate set of transforms for manipulating the tests at the
+    task-level. Currently only used for setting the taskcluster proxy setting and
+    the scopes required for perftest secrets.
+    """
+    from gecko_taskgraph.transforms.test.raptor import (
+        task_transforms as raptor_transforms,
+    )
+
+    for task in tasks:
+        if task.get("extra", {}).get("suite", "") != "raptor":
+            yield task
+            continue
+
+        yield from raptor_transforms(config, [task])
+
+
+@transforms.add
+def task_name_from_label(config, tasks):
+    for task in tasks:
+        taskname = task.pop("name", None)
+        if "label" not in task:
+            if taskname is None:
+                raise Exception("task has neither a name nor a label")
+            task["label"] = "{}-{}".format(config.kind, taskname)
+        yield task
+
+
+UNSUPPORTED_SHIPPING_PRODUCT_ERROR = """\
+The shipping product {product} is not in the list of configured products in
+`taskcluster/ci/config.yml'.
+"""
+
+
+def validate_shipping_product(config, product):
+    if product not in config.graph_config["release-promotion"]["products"]:
+        raise Exception(UNSUPPORTED_SHIPPING_PRODUCT_ERROR.format(product=product))
+
+
+@transforms.add
+def validate(config, tasks):
+    for task in tasks:
+        validate_schema(
+            task_description_schema,
+            task,
+            "In task {!r}:".format(task.get("label", "?no-label?")),
+        )
+        validate_schema(
+            payload_builders[task["worker"]["implementation"]].schema,
+            task["worker"],
+            "In task.run {!r}:".format(task.get("label", "?no-label?")),
+        )
+        if task["shipping-product"] is not None:
+            validate_shipping_product(config, task["shipping-product"])
+        yield task
+
+
+@index_builder("generic")
+def add_generic_index_routes(config, task):
+    index = task.get("index")
+    routes = task.setdefault("routes", [])
+
+    verify_index(config, index)
+
+    subs = config.params.copy()
+    subs["job-name"] = index["job-name"]
+    subs["build_date_long"] = time.strftime(
+        "%Y.%m.%d.%Y%m%d%H%M%S", time.gmtime(config.params["build_date"])
+    )
+    subs["build_date"] = time.strftime(
+        "%Y.%m.%d", time.gmtime(config.params["build_date"])
+    )
+    subs["product"] = index["product"]
+    subs["trust-domain"] = config.graph_config["trust-domain"]
+    subs["branch_rev"] = get_branch_rev(config)
+
+    project = config.params.get("project")
+
+    for tpl in V2_ROUTE_TEMPLATES:
+        routes.append(tpl.format(**subs))
+
+    # Additionally alias all tasks for "trunk" repos into a common
+    # namespace.
+    if project and project in TRUNK_PROJECTS:
+        for tpl in V2_TRUNK_ROUTE_TEMPLATES:
+            routes.append(tpl.format(**subs))
+
+    return task
+
+
+@index_builder("shippable")
+def add_shippable_index_routes(config, task):
+    index = task.get("index")
+    routes = task.setdefault("routes", [])
+
+    verify_index(config, index)
+
+    subs = config.params.copy()
+    subs["job-name"] = index["job-name"]
+    subs["build_date_long"] = time.strftime(
+        "%Y.%m.%d.%Y%m%d%H%M%S", time.gmtime(config.params["build_date"])
+    )
+    subs["build_date"] = time.strftime(
+        "%Y.%m.%d", time.gmtime(config.params["build_date"])
+    )
+    subs["product"] = index["product"]
+    subs["trust-domain"] = config.graph_config["trust-domain"]
+    subs["branch_rev"] = get_branch_rev(config)
+
+    for tpl in V2_SHIPPABLE_TEMPLATES:
+        routes.append(tpl.format(**subs))
+
+    # Also add routes for en-US
+    task = add_shippable_l10n_index_routes(config, task, force_locale="en-US")
+
+    return task
+
+
+@index_builder("shippable-with-multi-l10n")
+def add_shippable_multi_index_routes(config, task):
+    task = add_shippable_index_routes(config, task)
+    task = add_l10n_index_routes(config, task, force_locale="multi")
+    return task
+
+
+@index_builder("l10n")
+def add_l10n_index_routes(config, task, force_locale=None):
+    index = task.get("index")
+    routes = task.setdefault("routes", [])
+
+    verify_index(config, index)
+
+    subs = config.params.copy()
+    subs["job-name"] = index["job-name"]
+    subs["build_date_long"] = time.strftime(
+        "%Y.%m.%d.%Y%m%d%H%M%S", time.gmtime(config.params["build_date"])
+    )
+    subs["product"] = index["product"]
+    subs["trust-domain"] = config.graph_config["trust-domain"]
+    subs["branch_rev"] = get_branch_rev(config)
+
+    locales = task["attributes"].get(
+        "chunk_locales", task["attributes"].get("all_locales")
+    )
+    # Some tasks has only one locale set
+    if task["attributes"].get("locale"):
+        locales = [task["attributes"]["locale"]]
+
+    if force_locale:
+        # Used for en-US and multi-locale
+        locales = [force_locale]
+
+    if not locales:
+        raise Exception("Error: Unable to use l10n index for tasks without locales")
+
+    # If there are too many locales, we can't write a route for all of them
+    # See Bug 1323792
+    if len(locales) > 18:  # 18 * 3 = 54, max routes = 64
+        return task
+
+    for locale in locales:
+        for tpl in V2_L10N_TEMPLATES:
+            routes.append(tpl.format(locale=locale, **subs))
+
+    return task
+
+
+@index_builder("shippable-l10n")
+def add_shippable_l10n_index_routes(config, task, force_locale=None):
+    index = task.get("index")
+    routes = task.setdefault("routes", [])
+
+    verify_index(config, index)
+
+    subs = config.params.copy()
+    subs["job-name"] = index["job-name"]
+    subs["build_date_long"] = time.strftime(
+        "%Y.%m.%d.%Y%m%d%H%M%S", time.gmtime(config.params["build_date"])
+    )
+    subs["product"] = index["product"]
+    subs["trust-domain"] = config.graph_config["trust-domain"]
+    subs["branch_rev"] = get_branch_rev(config)
+
+    locales = task["attributes"].get(
+        "chunk_locales", task["attributes"].get("all_locales")
+    )
+    # Some tasks has only one locale set
+    if task["attributes"].get("locale"):
+        locales = [task["attributes"]["locale"]]
+
+    if force_locale:
+        # Used for en-US and multi-locale
+        locales = [force_locale]
+
+    if not locales:
+        raise Exception("Error: Unable to use l10n index for tasks without locales")
+
+    # If there are too many locales, we can't write a route for all of them
+    # See Bug 1323792
+    if len(locales) > 18:  # 18 * 3 = 54, max routes = 64
+        return task
+
+    for locale in locales:
+        for tpl in V2_SHIPPABLE_L10N_TEMPLATES:
+            routes.append(tpl.format(locale=locale, **subs))
+
+    return task
+
+
+def add_geckoview_index_routes(config, task):
+    index = task.get("index")
+    routes = task.setdefault("routes", [])
+    geckoview_version = _compute_geckoview_version(
+        config.params["app_version"], config.params["moz_build_date"]
+    )
+
+    subs = {
+        "geckoview-version": geckoview_version,
+        "job-name": index["job-name"],
+        "product": index["product"],
+        "project": config.params["project"],
+        "trust-domain": config.graph_config["trust-domain"],
+    }
+    routes.append(V2_GECKOVIEW_RELEASE.format(**subs))
+
+    return task
+
+
+@index_builder("android-shippable")
+def add_android_shippable_index_routes(config, task):
+    task = add_shippable_index_routes(config, task)
+    task = add_geckoview_index_routes(config, task)
+
+    return task
+
+
+@index_builder("android-shippable-with-multi-l10n")
+def add_android_shippable_multi_index_routes(config, task):
+    task = add_shippable_multi_index_routes(config, task)
+    task = add_geckoview_index_routes(config, task)
+
+    return task
+
+
+@transforms.add
+def add_index_routes(config, tasks):
+    for task in tasks:
+        index = task.get("index", {})
+
+        # The default behavior is to rank tasks according to their tier
+        extra_index = task.setdefault("extra", {}).setdefault("index", {})
+        rank = index.get("rank", "by-tier")
+
+        if rank == "by-tier":
+            # rank is zero for non-tier-1 tasks and based on pushid for others;
+            # this sorts tier-{2,3} builds below tier-1 in the index
+            tier = task.get("treeherder", {}).get("tier", 3)
+            extra_index["rank"] = 0 if tier > 1 else int(config.params["build_date"])
+        elif rank == "build_date":
+            extra_index["rank"] = int(config.params["build_date"])
+        else:
+            extra_index["rank"] = rank
+
+        if not index:
+            yield task
+            continue
+
+        index_type = index.get("type", "generic")
+        task = index_builders[index_type](config, task)
+
+        del task["index"]
+        yield task
+
+
+@transforms.add
+def try_task_config_env(config, tasks):
+    """Set environment variables in the task."""
+    env = config.params["try_task_config"].get("env")
+    if not env:
+        yield from tasks
+        return
+
+    # Find all implementations that have an 'env' key.
+    implementations = {
+        name
+        for name, builder in payload_builders.items()
+        if "env" in builder.schema.schema
+    }
+    for task in tasks:
+        if task["worker"]["implementation"] in implementations:
+            task["worker"]["env"].update(env)
+        yield task
+
+
+@transforms.add
+def try_task_config_chemspill_prio(config, tasks):
+    """Increase the priority from lowest and very-low -> low, but leave others unchanged."""
+    chemspill_prio = config.params["try_task_config"].get("chemspill-prio")
+    if not chemspill_prio:
+        yield from tasks
+        return
+
+    for task in tasks:
+        if task["priority"] in ("lowest", "very-low"):
+            task["priority"] = "low"
+        yield task
+
+
+@transforms.add
+def try_task_config_routes(config, tasks):
+    """Set routes in the task."""
+    routes = config.params["try_task_config"].get("routes")
+    for task in tasks:
+        if routes:
+            task_routes = task.setdefault("routes", [])
+            task_routes.extend(routes)
+        yield task
+
+
+@transforms.add
+def set_task_and_artifact_expiry(config, jobs):
+    """Set the default expiry for tasks and their artifacts.
+
+    These values are read from ci/config.yml
+    """
+    now = datetime.datetime.utcnow()
+    for job in jobs:
+        expires = get_expiration(config, job.get("expiration-policy", "default"))
+        job_expiry = job.setdefault("expires-after", expires)
+        job_expiry_from_now = fromNow(job_expiry)
+
+        for artifact in job["worker"].get("artifacts", ()):
+            artifact_expiry = artifact.setdefault("expires-after", expires)
+
+            # By using > instead of >=, there's a chance of mismatch
+            #   where the artifact expires sooner than the task.
+            #   There is no chance, however, of mismatch where artifacts
+            #   expire _after_ the task.
+            # Currently this leads to some build tasks having logs
+            #   that expire in 1 year while the task expires in 3 years.
+            if fromNow(artifact_expiry, now) > job_expiry_from_now:
+                artifact["expires-after"] = job_expiry
+
+        yield job
+
+
+@transforms.add
+def build_task(config, tasks):
+    for task in tasks:
+        level = str(config.params["level"])
+
+        task_worker_type = task["worker-type"]
+        worker_overrides = config.params["try_task_config"].get("worker-overrides", {})
+        if task_worker_type in worker_overrides:
+            worker_pool = worker_overrides[task_worker_type]
+            provisioner_id, worker_type = worker_pool.split("/", 1)
+        else:
+            provisioner_id, worker_type = get_worker_type(
+                config.graph_config,
+                config.params,
+                task_worker_type,
+            )
+        task["worker-type"] = "/".join([provisioner_id, worker_type])
+        project = config.params["project"]
+
+        routes = task.get("routes", [])
+        scopes = [
+            s.format(level=level, project=project) for s in task.get("scopes", [])
+        ]
+
+        # set up extra
+        extra = task.get("extra", {})
+        extra["parent"] = {"task-reference": "<decision>"}
+        task_th = task.get("treeherder")
+        if task_th:
+            extra.setdefault("treeherder-platform", task_th["platform"])
+            treeherder = extra.setdefault("treeherder", {})
+
+            machine_platform, collection = task_th["platform"].split("/", 1)
+            treeherder["machine"] = {"platform": machine_platform}
+            treeherder["collection"] = {collection: True}
+
+            group_names = config.graph_config["treeherder"]["group-names"]
+            groupSymbol, symbol = split_symbol(task_th["symbol"])
+            if groupSymbol != "?":
+                treeherder["groupSymbol"] = groupSymbol
+                if groupSymbol not in group_names:
+                    path = os.path.join(config.path, task.get("job-from", ""))
+                    raise Exception(UNKNOWN_GROUP_NAME.format(groupSymbol, path))
+                treeherder["groupName"] = group_names[groupSymbol]
+            treeherder["symbol"] = symbol
+            if len(symbol) > 25 or len(groupSymbol) > 25:
+                raise RuntimeError(
+                    "Treeherder group and symbol names must not be longer than "
+                    "25 characters: {} (see {})".format(
+                        task_th["symbol"],
+                        TC_TREEHERDER_SCHEMA_URL,
+                    )
+                )
+            treeherder["jobKind"] = task_th["kind"]
+            treeherder["tier"] = task_th["tier"]
+
+            branch_rev = get_branch_rev(config)
+
+            routes.append(
+                "{}.v2.{}.{}".format(
+                    TREEHERDER_ROUTE_ROOT,
+                    config.params["project"],
+                    branch_rev,
+                )
+            )
+
+        if "deadline-after" not in task:
+            task["deadline-after"] = "1 day"
+
+        if "priority" not in task:
+            task["priority"] = get_default_priority(
+                config.graph_config, config.params["project"]
+            )
+
+        tags = task.get("tags", {})
+        attributes = task.get("attributes", {})
+
+        tags.update(
+            {
+                "createdForUser": config.params["owner"],
+                "kind": config.kind,
+                "label": task["label"],
+                "retrigger": "true" if attributes.get("retrigger", False) else "false",
+            }
+        )
+
+        task_def = {
+            "provisionerId": provisioner_id,
+            "workerType": worker_type,
+            "routes": routes,
+            "created": {"relative-datestamp": "0 seconds"},
+            "deadline": {"relative-datestamp": task["deadline-after"]},
+            "expires": {"relative-datestamp": task["expires-after"]},
+            "scopes": scopes,
+            "metadata": {
+                "description": task["description"],
+                "name": task["label"],
+                "owner": config.params["owner"],
+                "source": config.params.file_url(config.path, pretty=True),
+            },
+            "extra": extra,
+            "tags": tags,
+            "priority": task["priority"],
+        }
+
+        if task.get("requires", None):
+            task_def["requires"] = task["requires"]
+
+        if task_th:
+            # link back to treeherder in description
+            th_job_link = (
+                "https://treeherder.mozilla.org/#/jobs?repo={}&revision={}&selectedTaskRun=<self>"
+            ).format(config.params["project"], branch_rev)
+            task_def["metadata"]["description"] = {
+                "task-reference": "{description} ([Treeherder job]({th_job_link}))".format(
+                    description=task_def["metadata"]["description"],
+                    th_job_link=th_job_link,
+                )
+            }
+
+        # add the payload and adjust anything else as required (e.g., scopes)
+        payload_builders[task["worker"]["implementation"]].builder(
+            config, task, task_def
+        )
+
+        # Resolve run-on-projects
+        build_platform = attributes.get("build_platform")
+        resolve_keyed_by(
+            task,
+            "run-on-projects",
+            item_name=task["label"],
+            **{"build-platform": build_platform},
+        )
+        attributes["run_on_projects"] = task.get("run-on-projects", ["all"])
+        attributes["always_target"] = task["always-target"]
+        # This logic is here since downstream tasks don't always match their
+        # upstream dependency's shipping_phase.
+        # A text_type task['shipping-phase'] takes precedence, then
+        # an existing attributes['shipping_phase'], then fall back to None.
+        if task.get("shipping-phase") is not None:
+            attributes["shipping_phase"] = task["shipping-phase"]
+        else:
+            attributes.setdefault("shipping_phase", None)
+        # shipping_product will always match the upstream task's
+        # shipping_product, so a pre-set existing attributes['shipping_product']
+        # takes precedence over task['shipping-product']. However, make sure
+        # we don't have conflicting values.
+        if task.get("shipping-product") and attributes.get("shipping_product") not in (
+            None,
+            task["shipping-product"],
+        ):
+            raise Exception(
+                "{} shipping_product {} doesn't match task shipping-product {}!".format(
+                    task["label"],
+                    attributes["shipping_product"],
+                    task["shipping-product"],
+                )
+            )
+        attributes.setdefault("shipping_product", task["shipping-product"])
+
+        # Set MOZ_AUTOMATION on all jobs.
+        if task["worker"]["implementation"] in (
+            "generic-worker",
+            "docker-worker",
+        ):
+            payload = task_def.get("payload")
+            if payload:
+                env = payload.setdefault("env", {})
+                env["MOZ_AUTOMATION"] = "1"
+
+        dependencies = task.get("dependencies", {})
+        if_dependencies = task.get("if-dependencies", [])
+        if if_dependencies:
+            for i, dep in enumerate(if_dependencies):
+                if dep in dependencies:
+                    if_dependencies[i] = dependencies[dep]
+                    continue
+
+                raise Exception(
+                    "{label} specifies '{dep}' in if-dependencies, "
+                    "but {dep} is not a dependency!".format(
+                        label=task["label"], dep=dep
+                    )
+                )
+
+        yield {
+            "label": task["label"],
+            "description": task["description"],
+            "task": task_def,
+            "dependencies": dependencies,
+            "if-dependencies": if_dependencies,
+            "soft-dependencies": task.get("soft-dependencies", []),
+            "attributes": attributes,
+            "optimization": task.get("optimization", None),
+        }
+
+
+@transforms.add
+def chain_of_trust(config, tasks):
+    for task in tasks:
+        if task["task"].get("payload", {}).get("features", {}).get("chainOfTrust"):
+            image = task.get("dependencies", {}).get("docker-image")
+            if image:
+                cot = (
+                    task["task"].setdefault("extra", {}).setdefault("chainOfTrust", {})
+                )
+                cot.setdefault("inputs", {})["docker-image"] = {
+                    "task-reference": "<docker-image>"
+                }
+        yield task
+
+
+@transforms.add
+def check_task_identifiers(config, tasks):
+    """Ensures that all tasks have well defined identifiers:
+    ``^[a-zA-Z0-9_-]{1,38}$``
+    """
+    e = re.compile("^[a-zA-Z0-9_-]{1,38}$")
+    for task in tasks:
+        for attrib in ("workerType", "provisionerId"):
+            if not e.match(task["task"][attrib]):
+                raise Exception(
+                    "task {}.{} is not a valid identifier: {}".format(
+                        task["label"], attrib, task["task"][attrib]
+                    )
+                )
+        yield task
+
+
+@transforms.add
+def check_task_dependencies(config, tasks):
+    """Ensures that tasks don't have more than 100 dependencies."""
+    for task in tasks:
+        if len(task["dependencies"]) > MAX_DEPENDENCIES:
+            raise Exception(
+                "task {}/{} has too many dependencies ({} > {})".format(
+                    config.kind,
+                    task["label"],
+                    len(task["dependencies"]),
+                    MAX_DEPENDENCIES,
+                )
+            )
+        yield task
+
+
+def check_caches_are_volumes(task):
+    """Ensures that all cache paths are defined as volumes.
+
+    Caches and volumes are the only filesystem locations whose content
+    isn't defined by the Docker image itself. Some caches are optional
+    depending on the job environment. We want paths that are potentially
+    caches to have as similar behavior regardless of whether a cache is
+    used. To help enforce this, we require that all paths used as caches
+    to be declared as Docker volumes. This check won't catch all offenders.
+    But it is better than nothing.
+    """
+    volumes = {s for s in task["worker"]["volumes"]}
+    paths = {c["mount-point"] for c in task["worker"].get("caches", [])}
+    missing = paths - volumes
+
+    if not missing:
+        return
+
+    raise Exception(
+        "task %s (image %s) has caches that are not declared as "
+        "Docker volumes: %s "
+        "(have you added them as VOLUMEs in the Dockerfile?)"
+        % (task["label"], task["worker"]["docker-image"], ", ".join(sorted(missing)))
+    )
+
+
+def check_required_volumes(task):
+    """
+    Ensures that all paths that are required to be volumes are defined as volumes.
+
+    Performance of writing to files in poor in directories not marked as
+    volumes, in docker. Ensure that paths that are often written to are marked
+    as volumes.
+    """
+    volumes = set(task["worker"]["volumes"])
+    paths = set(task["worker"].get("required-volumes", []))
+    missing = paths - volumes
+
+    if not missing:
+        return
+
+    raise Exception(
+        "task %s (image %s) has paths that should be volumes for peformance "
+        "that are not declared as Docker volumes: %s "
+        "(have you added them as VOLUMEs in the Dockerfile?)"
+        % (task["label"], task["worker"]["docker-image"], ", ".join(sorted(missing)))
+    )
+
+
+@transforms.add
+def check_run_task_caches(config, tasks):
+    """Audit for caches requiring run-task.
+
+    run-task manages caches in certain ways. If a cache managed by run-task
+    is used by a non run-task task, it could cause problems. So we audit for
+    that and make sure certain cache names are exclusive to run-task.
+
+    IF YOU ARE TEMPTED TO MAKE EXCLUSIONS TO THIS POLICY, YOU ARE LIKELY
+    CONTRIBUTING TECHNICAL DEBT AND WILL HAVE TO SOLVE MANY OF THE PROBLEMS
+    THAT RUN-TASK ALREADY SOLVES. THINK LONG AND HARD BEFORE DOING THAT.
+    """
+    re_reserved_caches = re.compile(
+        """^
+        (checkouts|tooltool-cache)
+    """,
+        re.VERBOSE,
+    )
+
+    re_sparse_checkout_cache = re.compile("^checkouts-sparse")
+
+    cache_prefix = "{trust_domain}-level-{level}-".format(
+        trust_domain=config.graph_config["trust-domain"],
+        level=config.params["level"],
+    )
+
+    suffix = _run_task_suffix()
+
+    for task in tasks:
+        payload = task["task"].get("payload", {})
+        command = payload.get("command") or [""]
+
+        main_command = command[0] if isinstance(command[0], str) else ""
+        run_task = main_command.endswith("run-task")
+
+        require_sparse_cache = False
+        have_sparse_cache = False
+
+        if run_task:
+            for arg in command[1:]:
+                if not isinstance(arg, str):
+                    continue
+
+                if arg == "--":
+                    break
+
+                if arg.startswith("--gecko-sparse-profile"):
+                    if "=" not in arg:
+                        raise Exception(
+                            "{} is specifying `--gecko-sparse-profile` to run-task "
+                            "as two arguments. Unable to determine if the sparse "
+                            "profile exists.".format(task["label"])
+                        )
+                    _, sparse_profile = arg.split("=", 1)
+                    if not os.path.exists(os.path.join(GECKO, sparse_profile)):
+                        raise Exception(
+                            "{} is using non-existant sparse profile {}.".format(
+                                task["label"], sparse_profile
+                            )
+                        )
+                    require_sparse_cache = True
+                    break
+
+        for cache in payload.get("cache", {}):
+            if not cache.startswith(cache_prefix):
+                raise Exception(
+                    "{} is using a cache ({}) which is not appropriate "
+                    "for its trust-domain and level. It should start with {}.".format(
+                        task["label"], cache, cache_prefix
+                    )
+                )
+
+            cache = cache[len(cache_prefix) :]
+
+            if re_sparse_checkout_cache.match(cache):
+                have_sparse_cache = True
+
+            if not re_reserved_caches.match(cache):
+                continue
+
+            if not run_task:
+                raise Exception(
+                    "%s is using a cache (%s) reserved for run-task "
+                    "change the task to use run-task or use a different "
+                    "cache name" % (task["label"], cache)
+                )
+
+            if not cache.endswith(suffix):
+                raise Exception(
+                    "%s is using a cache (%s) reserved for run-task "
+                    "but the cache name is not dependent on the contents "
+                    "of run-task; change the cache name to conform to the "
+                    "naming requirements" % (task["label"], cache)
+                )
+
+        if require_sparse_cache and not have_sparse_cache:
+            raise Exception(
+                "%s is using a sparse checkout but not using "
+                "a sparse checkout cache; change the checkout "
+                "cache name so it is sparse aware" % task["label"]
+            )
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/test/__init__.py b/taskcluster/gecko_taskgraph/transforms/test/__init__.py
new file mode 100644
index 0000000000..ac17554baa
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/__init__.py
@@ -0,0 +1,538 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+These transforms construct a task description to run the given test, based on a
+test description.  The implementation here is shared among all test kinds, but
+contains specific support for how we run tests in Gecko (via mozharness,
+invoked in particular ways).
+
+This is a good place to translate a test-description option such as
+`single-core: true` to the implementation of that option in a task description
+(worker options, mozharness commandline, environment variables, etc.)
+
+The test description should be fully formed by the time it reaches these
+transforms, and these transforms should not embody any specific knowledge about
+what should run where. this is the wrong place for special-casing platforms,
+for example - use `all_tests.py` instead.
+"""
+
+
+import logging
+from importlib import import_module
+
+from mozbuild.schedules import INCLUSIVE_COMPONENTS
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from voluptuous import Any, Exclusive, Optional, Required
+
+from gecko_taskgraph.optimize.schema import OptimizationSchema
+from gecko_taskgraph.transforms.test.other import get_mobile_project
+from gecko_taskgraph.util.chunking import manifest_loaders
+
+logger = logging.getLogger(__name__)
+transforms = TransformSequence()
+
+
+# Schema for a test description
+#
+# *****WARNING*****
+#
+# This is a great place for baffling cruft to accumulate, and that makes
+# everyone move more slowly.  Be considerate of your fellow hackers!
+# See the warnings in taskcluster/docs/how-tos.rst
+#
+# *****WARNING*****
+test_description_schema = Schema(
+    {
+        # description of the suite, for the task metadata
+        Required("description"): str,
+        # test suite category and name
+        Optional("suite"): Any(
+            optionally_keyed_by("variant", str),
+            {
+                Optional("category"): str,
+                Optional("name"): optionally_keyed_by("variant", str),
+            },
+        ),
+        # base work directory used to set up the task.
+        Optional("workdir"): optionally_keyed_by("test-platform", Any(str, "default")),
+        # the name by which this test suite is addressed in try syntax; defaults to
+        # the test-name.  This will translate to the `unittest_try_name` or
+        # `talos_try_name` attribute.
+        Optional("try-name"): str,
+        # additional tags to mark up this type of test
+        Optional("tags"): {str: object},
+        # the symbol, or group(symbol), under which this task should appear in
+        # treeherder.
+        Required("treeherder-symbol"): str,
+        # the value to place in task.extra.treeherder.machine.platform; ideally
+        # this is the same as build-platform, and that is the default, but in
+        # practice it's not always a match.
+        Optional("treeherder-machine-platform"): str,
+        # attributes to appear in the resulting task (later transforms will add the
+        # common attributes)
+        Optional("attributes"): {str: object},
+        # relative path (from config.path) to the file task was defined in
+        Optional("job-from"): str,
+        # The `run_on_projects` attribute, defaulting to "all".  This dictates the
+        # projects on which this task should be included in the target task set.
+        # See the attributes documentation for details.
+        #
+        # Note that the special case 'built-projects', the default, uses the parent
+        # build task's run-on-projects, meaning that tests run only on platforms
+        # that are built.
+        Optional("run-on-projects"): optionally_keyed_by(
+            "app",
+            "subtest",
+            "test-platform",
+            "test-name",
+            "variant",
+            Any([str], "built-projects"),
+        ),
+        # When set only run on projects where the build would already be running.
+        # This ensures tasks where this is True won't be the cause of the build
+        # running on a project it otherwise wouldn't have.
+        Optional("built-projects-only"): bool,
+        # the sheriffing tier for this task (default: set based on test platform)
+        Optional("tier"): optionally_keyed_by(
+            "test-platform", "variant", "app", "subtest", Any(int, "default")
+        ),
+        # number of chunks to create for this task.  This can be keyed by test
+        # platform by passing a dictionary in the `by-test-platform` key.  If the
+        # test platform is not found, the key 'default' will be tried.
+        Required("chunks"): optionally_keyed_by(
+            "test-platform", "variant", Any(int, "dynamic")
+        ),
+        # Custom 'test_manifest_loader' to use, overriding the one configured in the
+        # parameters. When 'null', no test chunking will be performed. Can also
+        # be used to disable "manifest scheduling".
+        Optional("test-manifest-loader"): Any(None, *list(manifest_loaders)),
+        # the time (with unit) after which this task is deleted; default depends on
+        # the branch (see below)
+        Optional("expires-after"): str,
+        # The different configurations that should be run against this task, defined
+        # in the TEST_VARIANTS object in the variant.py transforms.
+        Optional("variants"): [str],
+        # Whether to run this task without any variants applied.
+        Required("run-without-variant"): optionally_keyed_by("test-platform", bool),
+        # The EC2 instance size to run these tests on.
+        Required("instance-size"): optionally_keyed_by(
+            "test-platform", Any("default", "large", "xlarge")
+        ),
+        # type of virtualization or hardware required by test.
+        Required("virtualization"): optionally_keyed_by(
+            "test-platform", Any("virtual", "virtual-with-gpu", "hardware")
+        ),
+        # Whether the task requires loopback audio or video (whatever that may mean
+        # on the platform)
+        Required("loopback-audio"): bool,
+        Required("loopback-video"): bool,
+        # Whether the test can run using a software GL implementation on Linux
+        # using the GL compositor. May not be used with "legacy" sized instances
+        # due to poor LLVMPipe performance (bug 1296086).  Defaults to true for
+        # unit tests on linux platforms and false otherwise
+        Optional("allow-software-gl-layers"): bool,
+        # For tasks that will run in docker-worker, this is the
+        # name of the docker image or in-tree docker image to run the task in.  If
+        # in-tree, then a dependency will be created automatically.  This is
+        # generally `desktop-test`, or an image that acts an awful lot like it.
+        Required("docker-image"): optionally_keyed_by(
+            "test-platform",
+            Any(
+                # a raw Docker image path (repo/image:tag)
+                str,
+                # an in-tree generated docker image (from `taskcluster/docker/<name>`)
+                {"in-tree": str},
+                # an indexed docker image
+                {"indexed": str},
+            ),
+        ),
+        # seconds of runtime after which the task will be killed.  Like 'chunks',
+        # this can be keyed by test platform, but also variant.
+        Required("max-run-time"): optionally_keyed_by(
+            "test-platform", "subtest", "variant", "app", int
+        ),
+        # the exit status code that indicates the task should be retried
+        Optional("retry-exit-status"): [int],
+        # Whether to perform a gecko checkout.
+        Required("checkout"): bool,
+        # Wheter to perform a machine reboot after test is done
+        Optional("reboot"): Any(False, "always", "on-exception", "on-failure"),
+        # What to run
+        Required("mozharness"): {
+            # the mozharness script used to run this task
+            Required("script"): optionally_keyed_by("test-platform", str),
+            # the config files required for the task
+            Required("config"): optionally_keyed_by("test-platform", [str]),
+            # mochitest flavor for mochitest runs
+            Optional("mochitest-flavor"): str,
+            # any additional actions to pass to the mozharness command
+            Optional("actions"): [str],
+            # additional command-line options for mozharness, beyond those
+            # automatically added
+            Required("extra-options"): optionally_keyed_by("test-platform", [str]),
+            # the artifact name (including path) to test on the build task; this is
+            # generally set in a per-kind transformation
+            Optional("build-artifact-name"): str,
+            Optional("installer-url"): str,
+            # If not false, tooltool downloads will be enabled via relengAPIProxy
+            # for either just public files, or all files.  Not supported on Windows
+            Required("tooltool-downloads"): Any(
+                False,
+                "public",
+                "internal",
+            ),
+            # Add --blob-upload-branch=<project> mozharness parameter
+            Optional("include-blob-upload-branch"): bool,
+            # The setting for --download-symbols (if omitted, the option will not
+            # be passed to mozharness)
+            Optional("download-symbols"): Any(True, "ondemand"),
+            # If set, then MOZ_NODE_PATH=/usr/local/bin/node is included in the
+            # environment.  This is more than just a helpful path setting -- it
+            # causes xpcshell tests to start additional servers, and runs
+            # additional tests.
+            Required("set-moz-node-path"): bool,
+            # If true, include chunking information in the command even if the number
+            # of chunks is 1
+            Required("chunked"): optionally_keyed_by("test-platform", bool),
+            Required("requires-signed-builds"): optionally_keyed_by(
+                "test-platform", "variant", bool
+            ),
+        },
+        # The set of test manifests to run.
+        Optional("test-manifests"): Any(
+            [str],
+            {"active": [str], "skipped": [str]},
+        ),
+        # The current chunk (if chunking is enabled).
+        Optional("this-chunk"): int,
+        # os user groups for test task workers; required scopes, will be
+        # added automatically
+        Optional("os-groups"): optionally_keyed_by("test-platform", [str]),
+        Optional("run-as-administrator"): optionally_keyed_by("test-platform", bool),
+        # -- values supplied by the task-generation infrastructure
+        # the platform of the build this task is testing
+        Required("build-platform"): str,
+        # the label of the build task generating the materials to test
+        Required("build-label"): str,
+        # the label of the signing task generating the materials to test.
+        # Signed builds are used in xpcshell tests on Windows, for instance.
+        Optional("build-signing-label"): optionally_keyed_by("variant", str),
+        # the build's attributes
+        Required("build-attributes"): {str: object},
+        # the platform on which the tests will run
+        Required("test-platform"): str,
+        # limit the test-platforms (as defined in test-platforms.yml)
+        # that the test will run on
+        Optional("limit-platforms"): optionally_keyed_by("app", "subtest", [str]),
+        # the name of the test (the key in tests.yml)
+        Required("test-name"): str,
+        # the product name, defaults to firefox
+        Optional("product"): str,
+        # conditional files to determine when these tests should be run
+        Exclusive("when", "optimization"): {
+            Optional("files-changed"): [str],
+        },
+        # Optimization to perform on this task during the optimization phase.
+        # Optimizations are defined in taskcluster/gecko_taskgraph/optimize.py.
+        Exclusive("optimization", "optimization"): OptimizationSchema,
+        # The SCHEDULES component for this task; this defaults to the suite
+        # (not including the flavor) but can be overridden here.
+        Exclusive("schedules-component", "optimization"): Any(
+            str,
+            [str],
+        ),
+        Optional("worker-type"): optionally_keyed_by(
+            "test-platform",
+            Any(str, None),
+        ),
+        Optional(
+            "require-signed-extensions",
+            description="Whether the build being tested requires extensions be signed.",
+        ): optionally_keyed_by("release-type", "test-platform", bool),
+        # The target name, specifying the build artifact to be tested.
+        # If None or not specified, a transform sets the target based on OS:
+        # target.dmg (Mac), target.apk (Android), target.tar.bz2 (Linux),
+        # or target.zip (Windows).
+        Optional("target"): optionally_keyed_by(
+            "app",
+            "test-platform",
+            "variant",
+            Any(
+                str,
+                None,
+                {Required("index"): str, Required("name"): str},
+            ),
+        ),
+        # A list of artifacts to install from 'fetch' tasks. Validation deferred
+        # to 'job' transforms.
+        Optional("fetches"): object,
+        # Raptor / browsertime specific keys, defer validation to 'raptor.py'
+        # transform.
+        Optional("raptor"): object,
+        # Raptor / browsertime specific keys that need to be here since 'raptor' schema
+        # is evluated *before* test_description_schema
+        Optional("app"): str,
+        Optional("subtest"): str,
+        # Define if a given task supports artifact builds or not, see bug 1695325.
+        Optional("supports-artifact-builds"): bool,
+    }
+)
+
+
+@transforms.add
+def handle_keyed_by_mozharness(config, tasks):
+    """Resolve a mozharness field if it is keyed by something"""
+    fields = [
+        "mozharness",
+        "mozharness.chunked",
+        "mozharness.config",
+        "mozharness.extra-options",
+        "mozharness.script",
+    ]
+    for task in tasks:
+        for field in fields:
+            resolve_keyed_by(
+                task,
+                field,
+                item_name=task["test-name"],
+                enforce_single_match=False,
+            )
+        yield task
+
+
+@transforms.add
+def set_defaults(config, tasks):
+    for task in tasks:
+        build_platform = task["build-platform"]
+        if build_platform.startswith("android"):
+            # all Android test tasks download internal objects from tooltool
+            task["mozharness"]["tooltool-downloads"] = "internal"
+            task["mozharness"]["actions"] = ["get-secrets"]
+
+            # loopback-video is always true for Android, but false for other
+            # platform phyla
+            task["loopback-video"] = True
+        task["mozharness"]["set-moz-node-path"] = True
+
+        # software-gl-layers is only meaningful on linux unittests, where it defaults to True
+        if task["test-platform"].startswith("linux") and task["suite"] not in [
+            "talos",
+            "raptor",
+        ]:
+            task.setdefault("allow-software-gl-layers", True)
+        else:
+            task["allow-software-gl-layers"] = False
+
+        task.setdefault("try-name", task["test-name"])
+        task.setdefault("os-groups", [])
+        task.setdefault("run-as-administrator", False)
+        task.setdefault("chunks", 1)
+        task.setdefault("run-on-projects", "built-projects")
+        task.setdefault("built-projects-only", False)
+        task.setdefault("instance-size", "default")
+        task.setdefault("max-run-time", 3600)
+        task.setdefault("reboot", False)
+        task.setdefault("virtualization", "virtual")
+        task.setdefault("loopback-audio", False)
+        task.setdefault("loopback-video", False)
+        task.setdefault("limit-platforms", [])
+        task.setdefault("docker-image", {"in-tree": "ubuntu1804-test"})
+        task.setdefault("checkout", False)
+        task.setdefault("require-signed-extensions", False)
+        task.setdefault("run-without-variant", True)
+        task.setdefault("variants", [])
+        task.setdefault("supports-artifact-builds", True)
+
+        task["mozharness"].setdefault("extra-options", [])
+        task["mozharness"].setdefault("requires-signed-builds", False)
+        task["mozharness"].setdefault("tooltool-downloads", "public")
+        task["mozharness"].setdefault("set-moz-node-path", False)
+        task["mozharness"].setdefault("chunked", False)
+        yield task
+
+
+transforms.add_validate(test_description_schema)
+
+
+@transforms.add
+def run_variant_transforms(config, tasks):
+    """Variant transforms are run as soon as possible to allow other transforms
+    to key by variant."""
+    for task in tasks:
+        xforms = TransformSequence()
+        mod = import_module("gecko_taskgraph.transforms.test.variant")
+        xforms.add(mod.transforms)
+
+        yield from xforms(config, [task])
+
+
+@transforms.add
+def resolve_keys(config, tasks):
+    keys = ("require-signed-extensions", "run-without-variant", "suite", "suite.name")
+    for task in tasks:
+        for key in keys:
+            resolve_keyed_by(
+                task,
+                key,
+                item_name=task["test-name"],
+                enforce_single_match=False,
+                **{
+                    "release-type": config.params["release_type"],
+                    "variant": task["attributes"].get("unittest_variant"),
+                },
+            )
+        yield task
+
+
+@transforms.add
+def run_remaining_transforms(config, tasks):
+    """Runs other transform files next to this module."""
+    # List of modules to load transforms from in order.
+    transform_modules = (
+        ("raptor", lambda t: t["suite"] == "raptor"),
+        ("other", None),
+        ("worker", None),
+        # These transforms should always run last as there is never any
+        # difference in configuration from one chunk to another (other than
+        # chunk number).
+        ("chunk", None),
+    )
+
+    for task in tasks:
+        xforms = TransformSequence()
+        for name, filterfn in transform_modules:
+            if filterfn and not filterfn(task):
+                continue
+
+            mod = import_module(f"gecko_taskgraph.transforms.test.{name}")
+            xforms.add(mod.transforms)
+
+        yield from xforms(config, [task])
+
+
+@transforms.add
+def make_job_description(config, tasks):
+    """Convert *test* descriptions to *job* descriptions (input to
+    gecko_taskgraph.transforms.job)"""
+
+    for task in tasks:
+        attributes = task.get("attributes", {})
+
+        mobile = get_mobile_project(task)
+        if mobile and (mobile not in task["test-name"]):
+            label = "{}-{}-{}-{}".format(
+                config.kind, task["test-platform"], mobile, task["test-name"]
+            )
+        else:
+            label = "{}-{}-{}".format(
+                config.kind, task["test-platform"], task["test-name"]
+            )
+
+        try_name = task["try-name"]
+        if attributes.get("unittest_variant"):
+            suffix = task.pop("variant-suffix")
+            label += suffix
+            try_name += suffix
+
+        if task["chunks"] > 1:
+            label += "-{}".format(task["this-chunk"])
+
+        build_label = task["build-label"]
+
+        if task["suite"] == "talos":
+            attr_try_name = "talos_try_name"
+        elif task["suite"] == "raptor":
+            attr_try_name = "raptor_try_name"
+        else:
+            attr_try_name = "unittest_try_name"
+
+        attr_build_platform, attr_build_type = task["build-platform"].split("/", 1)
+        attributes.update(
+            {
+                "build_platform": attr_build_platform,
+                "build_type": attr_build_type,
+                "test_platform": task["test-platform"],
+                "test_chunk": str(task["this-chunk"]),
+                "supports-artifact-builds": task["supports-artifact-builds"],
+                attr_try_name: try_name,
+            }
+        )
+
+        if "test-manifests" in task:
+            attributes["test_manifests"] = task["test-manifests"]
+
+        jobdesc = {}
+        name = "{}-{}".format(task["test-platform"], task["test-name"])
+        jobdesc["name"] = name
+        jobdesc["label"] = label
+        jobdesc["description"] = task["description"]
+        jobdesc["attributes"] = attributes
+        jobdesc["dependencies"] = {"build": build_label}
+        jobdesc["job-from"] = task["job-from"]
+
+        if task.get("fetches"):
+            jobdesc["fetches"] = task["fetches"]
+
+        if task["mozharness"]["requires-signed-builds"] is True:
+            jobdesc["dependencies"]["build-signing"] = task["build-signing-label"]
+
+        if "expires-after" in task:
+            jobdesc["expires-after"] = task["expires-after"]
+
+        jobdesc["routes"] = []
+        jobdesc["run-on-projects"] = sorted(task["run-on-projects"])
+        jobdesc["scopes"] = []
+        jobdesc["tags"] = task.get("tags", {})
+        jobdesc["extra"] = {
+            "chunks": {
+                "current": task["this-chunk"],
+                "total": task["chunks"],
+            },
+            "suite": attributes["unittest_suite"],
+            "test-setting": task.pop("test-setting"),
+        }
+        jobdesc["treeherder"] = {
+            "symbol": task["treeherder-symbol"],
+            "kind": "test",
+            "tier": task["tier"],
+            "platform": task.get("treeherder-machine-platform", task["build-platform"]),
+        }
+
+        schedules = task.get("schedules-component", [])
+        if task.get("when"):
+            # This may still be used by comm-central.
+            jobdesc["when"] = task["when"]
+        elif "optimization" in task:
+            jobdesc["optimization"] = task["optimization"]
+        elif set(schedules) & set(INCLUSIVE_COMPONENTS):
+            jobdesc["optimization"] = {"test-inclusive": schedules}
+        else:
+            jobdesc["optimization"] = {"test": schedules}
+
+        run = jobdesc["run"] = {}
+        run["using"] = "mozharness-test"
+        run["test"] = task
+
+        if "workdir" in task:
+            run["workdir"] = task.pop("workdir")
+
+        jobdesc["worker-type"] = task.pop("worker-type")
+
+        if "worker" in task:
+            jobdesc["worker"] = task.pop("worker")
+
+        if task.get("fetches"):
+            jobdesc["fetches"] = task.pop("fetches")
+
+        yield jobdesc
+
+
+def normpath(path):
+    return path.replace("/", "\\")
+
+
+def get_firefox_version():
+    with open("browser/config/version.txt") as f:
+        return f.readline().strip()
diff --git a/taskcluster/gecko_taskgraph/transforms/test/chunk.py b/taskcluster/gecko_taskgraph/transforms/test/chunk.py
new file mode 100644
index 0000000000..f6442e3755
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/chunk.py
@@ -0,0 +1,262 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import json
+
+import taskgraph
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.attributes import keymatch
+from taskgraph.util.treeherder import join_symbol, split_symbol
+
+from gecko_taskgraph.util.attributes import is_try
+from gecko_taskgraph.util.chunking import (
+    DefaultLoader,
+    chunk_manifests,
+    get_manifest_loader,
+    get_runtimes,
+    guess_mozinfo_from_task,
+)
+from gecko_taskgraph.util.copy_task import copy_task
+from gecko_taskgraph.util.perfile import perfile_number_of_chunks
+
+DYNAMIC_CHUNK_DURATION = 20 * 60  # seconds
+"""The approximate time each test chunk should take to run."""
+
+
+DYNAMIC_CHUNK_MULTIPLIER = {
+    # Desktop xpcshell tests run in parallel. Reduce the total runtime to
+    # compensate.
+    "^(?!android).*-xpcshell.*": 0.2,
+}
+"""A multiplication factor to tweak the total duration per platform / suite."""
+
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_test_verify_chunks(config, tasks):
+    """Set the number of chunks we use for test-verify."""
+    for task in tasks:
+        if any(task["suite"].startswith(s) for s in ("test-verify", "test-coverage")):
+            env = config.params.get("try_task_config", {}) or {}
+            env = env.get("templates", {}).get("env", {})
+            task["chunks"] = perfile_number_of_chunks(
+                is_try(config.params),
+                env.get("MOZHARNESS_TEST_PATHS", ""),
+                config.params.get("head_repository", ""),
+                config.params.get("head_rev", ""),
+                task["test-name"],
+            )
+
+            # limit the number of chunks we run for test-verify mode because
+            # test-verify is comprehensive and takes a lot of time, if we have
+            # >30 tests changed, this is probably an import of external tests,
+            # or a patch renaming/moving files in bulk
+            maximum_number_verify_chunks = 3
+            if task["chunks"] > maximum_number_verify_chunks:
+                task["chunks"] = maximum_number_verify_chunks
+
+        yield task
+
+
+@transforms.add
+def set_test_manifests(config, tasks):
+    """Determine the set of test manifests that should run in this task."""
+
+    for task in tasks:
+        # When a task explicitly requests no 'test_manifest_loader', test
+        # resolving will happen at test runtime rather than in the taskgraph.
+        if "test-manifest-loader" in task and task["test-manifest-loader"] is None:
+            yield task
+            continue
+
+        # Set 'tests_grouped' to "1", so we can differentiate between suites that are
+        # chunked at the test runtime and those that are chunked in the taskgraph.
+        task.setdefault("tags", {})["tests_grouped"] = "1"
+
+        if taskgraph.fast:
+            # We want to avoid evaluating manifests when taskgraph.fast is set. But
+            # manifests are required for dynamic chunking. Just set the number of
+            # chunks to one in this case.
+            if task["chunks"] == "dynamic":
+                task["chunks"] = 1
+            yield task
+            continue
+
+        manifests = task.get("test-manifests")
+        if manifests:
+            if isinstance(manifests, list):
+                task["test-manifests"] = {"active": manifests, "skipped": []}
+            yield task
+            continue
+
+        mozinfo = guess_mozinfo_from_task(
+            task, config.params.get("head_repository", "")
+        )
+
+        loader_name = task.pop(
+            "test-manifest-loader", config.params["test_manifest_loader"]
+        )
+        loader = get_manifest_loader(loader_name, config.params)
+
+        task["test-manifests"] = loader.get_manifests(
+            task["suite"],
+            frozenset(mozinfo.items()),
+        )
+
+        # When scheduling with test paths, we often find manifests scheduled but all tests
+        # are skipped on a given config.  This will remove the task from the task set if
+        # no manifests have active tests for the given task/config
+        mh_test_paths = {}
+        if "MOZHARNESS_TEST_PATHS" in config.params.get("try_task_config", {}).get(
+            "env", {}
+        ):
+            mh_test_paths = json.loads(
+                config.params["try_task_config"]["env"]["MOZHARNESS_TEST_PATHS"]
+            )
+
+        if task["attributes"]["unittest_suite"] in mh_test_paths.keys():
+            input_paths = mh_test_paths[task["attributes"]["unittest_suite"]]
+            remaining_manifests = []
+
+            # if we have web-platform tests incoming, just yield task
+            for m in input_paths:
+                if m.startswith("testing/web-platform/tests/"):
+                    if not isinstance(loader, DefaultLoader):
+                        task["chunks"] = "dynamic"
+                    yield task
+                    break
+
+            # input paths can exist in other directories (i.e. [../../dir/test.js])
+            # we need to look for all [active] manifests that include tests in the path
+            for m in input_paths:
+                if [tm for tm in task["test-manifests"]["active"] if tm.startswith(m)]:
+                    remaining_manifests.append(m)
+
+            # look in the 'other' manifests
+            for m in input_paths:
+                man = m
+                for tm in task["test-manifests"]["other_dirs"]:
+                    matched_dirs = [
+                        dp
+                        for dp in task["test-manifests"]["other_dirs"].get(tm)
+                        if dp.startswith(man)
+                    ]
+                    if matched_dirs:
+                        if tm not in task["test-manifests"]["active"]:
+                            continue
+                        if m not in remaining_manifests:
+                            remaining_manifests.append(m)
+
+            if remaining_manifests == []:
+                continue
+
+        # The default loader loads all manifests. If we use a non-default
+        # loader, we'll only run some subset of manifests and the hardcoded
+        # chunk numbers will no longer be valid. Dynamic chunking should yield
+        # better results.
+        if not isinstance(loader, DefaultLoader):
+            task["chunks"] = "dynamic"
+
+        yield task
+
+
+@transforms.add
+def resolve_dynamic_chunks(config, tasks):
+    """Determine how many chunks are needed to handle the given set of manifests."""
+
+    for task in tasks:
+        if task["chunks"] != "dynamic":
+            yield task
+            continue
+
+        if not task.get("test-manifests"):
+            raise Exception(
+                "{} must define 'test-manifests' to use dynamic chunking!".format(
+                    task["test-name"]
+                )
+            )
+
+        runtimes = {
+            m: r
+            for m, r in get_runtimes(task["test-platform"], task["suite"]).items()
+            if m in task["test-manifests"]["active"]
+        }
+
+        # Truncate runtimes that are above the desired chunk duration. They
+        # will be assigned to a chunk on their own and the excess duration
+        # shouldn't cause additional chunks to be needed.
+        times = [min(DYNAMIC_CHUNK_DURATION, r) for r in runtimes.values()]
+        avg = round(sum(times) / len(times), 2) if times else 0
+        total = sum(times)
+
+        # If there are manifests missing from the runtimes data, fill them in
+        # with the average of all present manifests.
+        missing = [m for m in task["test-manifests"]["active"] if m not in runtimes]
+        total += avg * len(missing)
+
+        # Apply any chunk multipliers if found.
+        key = "{}-{}".format(task["test-platform"], task["test-name"])
+        matches = keymatch(DYNAMIC_CHUNK_MULTIPLIER, key)
+        if len(matches) > 1:
+            raise Exception(
+                "Multiple matching values for {} found while "
+                "determining dynamic chunk multiplier!".format(key)
+            )
+        elif matches:
+            total = total * matches[0]
+
+        chunks = int(round(total / DYNAMIC_CHUNK_DURATION))
+
+        # Make sure we never exceed the number of manifests, nor have a chunk
+        # length of 0.
+        task["chunks"] = min(chunks, len(task["test-manifests"]["active"])) or 1
+        yield task
+
+
+@transforms.add
+def split_chunks(config, tasks):
+    """Based on the 'chunks' key, split tests up into chunks by duplicating
+    them and assigning 'this-chunk' appropriately and updating the treeherder
+    symbol.
+    """
+
+    for task in tasks:
+        # If test-manifests are set, chunk them ahead of time to avoid running
+        # the algorithm more than once.
+        chunked_manifests = None
+        if "test-manifests" in task:
+            manifests = task["test-manifests"]
+            chunked_manifests = chunk_manifests(
+                task["suite"],
+                task["test-platform"],
+                task["chunks"],
+                manifests["active"],
+            )
+
+            # Add all skipped manifests to the first chunk of backstop pushes
+            # so they still show up in the logs. They won't impact runtime much
+            # and this way tools like ActiveData are still aware that they
+            # exist.
+            if config.params["backstop"] and manifests["active"]:
+                chunked_manifests[0].extend(manifests["skipped"])
+
+        for i in range(task["chunks"]):
+            this_chunk = i + 1
+
+            # copy the test and update with the chunk number
+            chunked = copy_task(task)
+            chunked["this-chunk"] = this_chunk
+
+            if chunked_manifests is not None:
+                chunked["test-manifests"] = sorted(chunked_manifests[i])
+
+            group, symbol = split_symbol(chunked["treeherder-symbol"])
+            if task["chunks"] > 1 or not symbol:
+                # add the chunk number to the TH symbol
+                symbol += str(this_chunk)
+                chunked["treeherder-symbol"] = join_symbol(group, symbol)
+
+            yield chunked
diff --git a/taskcluster/gecko_taskgraph/transforms/test/other.py b/taskcluster/gecko_taskgraph/transforms/test/other.py
new file mode 100644
index 0000000000..1c08d290e4
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/other.py
@@ -0,0 +1,1081 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import hashlib
+import json
+import re
+
+from mozbuild.schedules import INCLUSIVE_COMPONENTS
+from mozbuild.util import ReadOnlyDict
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.attributes import keymatch
+from taskgraph.util.keyed_by import evaluate_keyed_by
+from taskgraph.util.schema import Schema, resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_path, get_index_url
+from voluptuous import Any, Optional, Required
+
+from gecko_taskgraph.transforms.test.variant import TEST_VARIANTS
+from gecko_taskgraph.util.platforms import platform_family
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def limit_platforms(config, tasks):
+    for task in tasks:
+        if not task["limit-platforms"]:
+            yield task
+            continue
+
+        limited_platforms = {key: key for key in task["limit-platforms"]}
+        if keymatch(limited_platforms, task["test-platform"]):
+            yield task
+
+
+@transforms.add
+def handle_suite_category(config, tasks):
+    for task in tasks:
+        task.setdefault("suite", {})
+
+        if isinstance(task["suite"], str):
+            task["suite"] = {"name": task["suite"]}
+
+        suite = task["suite"].setdefault("name", task["test-name"])
+        category = task["suite"].setdefault("category", suite)
+
+        task.setdefault("attributes", {})
+        task["attributes"]["unittest_suite"] = suite
+        task["attributes"]["unittest_category"] = category
+
+        script = task["mozharness"]["script"]
+        category_arg = None
+        if suite.startswith("test-verify") or suite.startswith("test-coverage"):
+            pass
+        elif script in ("android_emulator_unittest.py", "android_hardware_unittest.py"):
+            category_arg = "--test-suite"
+        elif script == "desktop_unittest.py":
+            category_arg = f"--{category}-suite"
+
+        if category_arg:
+            task["mozharness"].setdefault("extra-options", [])
+            extra = task["mozharness"]["extra-options"]
+            if not any(arg.startswith(category_arg) for arg in extra):
+                extra.append(f"{category_arg}={suite}")
+
+        # From here on out we only use the suite name.
+        task["suite"] = suite
+        yield task
+
+
+@transforms.add
+def setup_talos(config, tasks):
+    """Add options that are specific to talos jobs (identified by suite=talos)"""
+    for task in tasks:
+        if task["suite"] != "talos":
+            yield task
+            continue
+
+        extra_options = task.setdefault("mozharness", {}).setdefault(
+            "extra-options", []
+        )
+        extra_options.append("--use-talos-json")
+
+        # win7 needs to test skip
+        if task["build-platform"].startswith("win32"):
+            extra_options.append("--add-option")
+            extra_options.append("--setpref,gfx.direct2d.disabled=true")
+
+        if config.params.get("project", None):
+            extra_options.append("--project=%s" % config.params["project"])
+
+        yield task
+
+
+@transforms.add
+def setup_browsertime_flag(config, tasks):
+    """Optionally add `--browsertime` flag to Raptor pageload tests."""
+
+    browsertime_flag = config.params["try_task_config"].get("browsertime", False)
+
+    for task in tasks:
+        if not browsertime_flag or task["suite"] != "raptor":
+            yield task
+            continue
+
+        if task["treeherder-symbol"].startswith("Rap"):
+            # The Rap group is subdivided as Rap{-fenix,-refbrow(...),
+            # so `taskgraph.util.treeherder.replace_group` isn't appropriate.
+            task["treeherder-symbol"] = task["treeherder-symbol"].replace(
+                "Rap", "Btime", 1
+            )
+
+        extra_options = task.setdefault("mozharness", {}).setdefault(
+            "extra-options", []
+        )
+        extra_options.append("--browsertime")
+
+        yield task
+
+
+@transforms.add
+def handle_artifact_prefix(config, tasks):
+    """Handle translating `artifact_prefix` appropriately"""
+    for task in tasks:
+        if task["build-attributes"].get("artifact_prefix"):
+            task.setdefault("attributes", {}).setdefault(
+                "artifact_prefix", task["build-attributes"]["artifact_prefix"]
+            )
+        yield task
+
+
+@transforms.add
+def set_treeherder_machine_platform(config, tasks):
+    """Set the appropriate task.extra.treeherder.machine.platform"""
+    translation = {
+        # Linux64 build platform for asan is specified differently to
+        # treeherder.
+        "macosx1100-64/opt": "osx-1100/opt",
+        "macosx1100-64-shippable/opt": "osx-1100-shippable/opt",
+        "win64-asan/opt": "windows10-64/asan",
+        "win64-aarch64/opt": "windows10-aarch64/opt",
+    }
+    for task in tasks:
+        # For most desktop platforms, the above table is not used for "regular"
+        # builds, so we'll always pick the test platform here.
+        # On macOS though, the regular builds are in the table.  This causes a
+        # conflict in `verify_task_graph_symbol` once you add a new test
+        # platform based on regular macOS builds, such as for QR.
+        # Since it's unclear if the regular macOS builds can be removed from
+        # the table, workaround the issue for QR.
+        if "android" in task["test-platform"] and "pgo/opt" in task["test-platform"]:
+            platform_new = task["test-platform"].replace("-pgo/opt", "/pgo")
+            task["treeherder-machine-platform"] = platform_new
+        elif "android-em-7.0-x86_64-qr" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        elif "android-em-7.0-x86_64-shippable-qr" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        elif "android-em-7.0-x86_64-lite-qr" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        elif "android-em-7.0-x86_64-shippable-lite-qr" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        elif "-qr" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"]
+        elif "android-hw" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"]
+        elif "android-em-7.0-x86_64" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        elif "android-em-7.0-x86" in task["test-platform"]:
+            task["treeherder-machine-platform"] = task["test-platform"].replace(
+                ".", "-"
+            )
+        # Bug 1602863 - must separately define linux64/asan and linux1804-64/asan
+        # otherwise causes an exception during taskgraph generation about
+        # duplicate treeherder platform/symbol.
+        elif "linux64-asan/opt" in task["test-platform"]:
+            task["treeherder-machine-platform"] = "linux64/asan"
+        elif "linux1804-asan/opt" in task["test-platform"]:
+            task["treeherder-machine-platform"] = "linux1804-64/asan"
+        else:
+            task["treeherder-machine-platform"] = translation.get(
+                task["build-platform"], task["test-platform"]
+            )
+        yield task
+
+
+@transforms.add
+def set_download_symbols(config, tasks):
+    """In general, we download symbols immediately for debug builds, but only
+    on demand for everything else. ASAN builds shouldn't download
+    symbols since they don't product symbol zips see bug 1283879"""
+    for task in tasks:
+        if task["test-platform"].split("/")[-1] == "debug":
+            task["mozharness"]["download-symbols"] = True
+        elif "asan" in task["build-platform"] or "tsan" in task["build-platform"]:
+            if "download-symbols" in task["mozharness"]:
+                del task["mozharness"]["download-symbols"]
+        else:
+            task["mozharness"]["download-symbols"] = "ondemand"
+        yield task
+
+
+@transforms.add
+def handle_keyed_by(config, tasks):
+    """Resolve fields that can be keyed by platform, etc."""
+    fields = [
+        "instance-size",
+        "docker-image",
+        "max-run-time",
+        "chunks",
+        "suite",
+        "run-on-projects",
+        "os-groups",
+        "run-as-administrator",
+        "workdir",
+        "worker-type",
+        "virtualization",
+        "fetches.fetch",
+        "fetches.toolchain",
+        "target",
+        "webrender-run-on-projects",
+        "mozharness.requires-signed-builds",
+        "build-signing-label",
+    ]
+    for task in tasks:
+        for field in fields:
+            resolve_keyed_by(
+                task,
+                field,
+                item_name=task["test-name"],
+                enforce_single_match=False,
+                project=config.params["project"],
+                variant=task["attributes"].get("unittest_variant"),
+            )
+        yield task
+
+
+@transforms.add
+def set_target(config, tasks):
+    for task in tasks:
+        build_platform = task["build-platform"]
+        target = None
+        if "target" in task:
+            target = task["target"]
+        if not target:
+            if build_platform.startswith("macosx"):
+                target = "target.dmg"
+            elif build_platform.startswith("android"):
+                target = "target.apk"
+            elif build_platform.startswith("win"):
+                target = "target.zip"
+            else:
+                target = "target.tar.bz2"
+
+        if isinstance(target, dict):
+            # TODO Remove hardcoded mobile artifact prefix
+            index_url = get_index_url(target["index"])
+            installer_url = "{}/artifacts/public/{}".format(index_url, target["name"])
+            task["mozharness"]["installer-url"] = installer_url
+        else:
+            task["mozharness"]["build-artifact-name"] = get_artifact_path(task, target)
+
+        yield task
+
+
+@transforms.add
+def setup_browsertime(config, tasks):
+    """Configure browsertime dependencies for Raptor pageload tests that have
+    `--browsertime` extra option."""
+
+    for task in tasks:
+        # We need to make non-trivial changes to various fetches, and our
+        # `by-test-platform` may not be "compatible" with existing
+        # `by-test-platform` filters.  Therefore we do everything after
+        # `handle_keyed_by` so that existing fields have been resolved down to
+        # simple lists.  But we use the `by-test-platform` machinery to express
+        # filters so that when the time comes to move browsertime into YAML
+        # files, the transition is straight-forward.
+        extra_options = task.get("mozharness", {}).get("extra-options", [])
+
+        if task["suite"] != "raptor" or "--webext" in extra_options:
+            yield task
+            continue
+
+        ts = {
+            "by-test-platform": {
+                "android.*": ["browsertime", "linux64-geckodriver", "linux64-node-16"],
+                "linux.*": ["browsertime", "linux64-geckodriver", "linux64-node-16"],
+                "macosx.*": ["browsertime", "macosx64-geckodriver", "macosx64-node-16"],
+                "windows.*aarch64.*": [
+                    "browsertime",
+                    "win32-geckodriver",
+                    "win32-node-16",
+                ],
+                "windows.*-32.*": ["browsertime", "win32-geckodriver", "win32-node-16"],
+                "windows.*-64.*": ["browsertime", "win64-geckodriver", "win64-node-16"],
+            },
+        }
+
+        task.setdefault("fetches", {}).setdefault("toolchain", []).extend(
+            evaluate_keyed_by(ts, "fetches.toolchain", task)
+        )
+
+        fs = {
+            "by-test-platform": {
+                "android.*": ["linux64-ffmpeg-4.4.1"],
+                "linux.*": ["linux64-ffmpeg-4.4.1"],
+                "macosx.*": ["mac64-ffmpeg-4.4.1"],
+                "windows.*aarch64.*": ["win64-ffmpeg-4.4.1"],
+                "windows.*-32.*": ["win64-ffmpeg-4.4.1"],
+                "windows.*-64.*": ["win64-ffmpeg-4.4.1"],
+            },
+        }
+
+        cd_fetches = {
+            "android.*": [
+                "linux64-chromedriver-109",
+                "linux64-chromedriver-110",
+                "linux64-chromedriver-111",
+                "linux64-chromedriver-112",
+                "linux64-chromedriver-113",
+                "linux64-chromedriver-114",
+            ],
+            "linux.*": [
+                "linux64-chromedriver-112",
+                "linux64-chromedriver-113",
+                "linux64-chromedriver-114",
+            ],
+            "macosx.*": [
+                "mac64-chromedriver-109",
+                "mac64-chromedriver-110",
+                "mac64-chromedriver-111",
+                "mac64-chromedriver-112",
+                "mac64-chromedriver-113",
+                "mac64-chromedriver-114",
+            ],
+            "windows.*aarch64.*": [
+                "win32-chromedriver-112",
+                "win32-chromedriver-113",
+                "win32-chromedriver-114",
+            ],
+            "windows.*-32.*": [
+                "win32-chromedriver-112",
+                "win32-chromedriver-113",
+                "win32-chromedriver-114",
+            ],
+            "windows.*-64.*": [
+                "win32-chromedriver-112",
+                "win32-chromedriver-113",
+                "win32-chromedriver-114",
+            ],
+        }
+
+        chromium_fetches = {
+            "linux.*": ["linux64-chromium"],
+            "macosx.*": ["mac-chromium"],
+            "windows.*aarch64.*": ["win32-chromium"],
+            "windows.*-32.*": ["win32-chromium"],
+            "windows.*-64.*": ["win64-chromium"],
+        }
+
+        cd_extracted_name = {
+            "windows": "{}chromedriver.exe",
+            "mac": "{}chromedriver",
+            "default": "{}chromedriver",
+        }
+
+        if "--app=chrome" in extra_options or "--app=chrome-m" in extra_options:
+            # Only add the chromedriver fetches when chrome is running
+            for platform in cd_fetches:
+                fs["by-test-platform"][platform].extend(cd_fetches[platform])
+        if "--app=chromium" in extra_options or "--app=custom-car" in extra_options:
+            for platform in chromium_fetches:
+                fs["by-test-platform"][platform].extend(chromium_fetches[platform])
+
+            # The chromedrivers for chromium are repackaged into the archives
+            # that we get the chromium binary from so we always have a compatible
+            # version.
+            cd_extracted_name = {
+                "windows": "chrome-win/chromedriver.exe",
+                "mac": "chrome-mac/chromedriver",
+                "default": "chrome-linux/chromedriver",
+            }
+
+        # Disable the Raptor install step
+        if "--app=chrome-m" in extra_options:
+            extra_options.append("--noinstall")
+
+        task.setdefault("fetches", {}).setdefault("fetch", []).extend(
+            evaluate_keyed_by(fs, "fetches.fetch", task)
+        )
+
+        extra_options.extend(
+            (
+                "--browsertime-browsertimejs",
+                "$MOZ_FETCHES_DIR/browsertime/node_modules/browsertime/bin/browsertime.js",
+            )
+        )  # noqa: E501
+
+        eos = {
+            "by-test-platform": {
+                "windows.*": [
+                    "--browsertime-node",
+                    "$MOZ_FETCHES_DIR/node/node.exe",
+                    "--browsertime-geckodriver",
+                    "$MOZ_FETCHES_DIR/geckodriver.exe",
+                    "--browsertime-chromedriver",
+                    "$MOZ_FETCHES_DIR/" + cd_extracted_name["windows"],
+                    "--browsertime-ffmpeg",
+                    "$MOZ_FETCHES_DIR/ffmpeg-4.4.1-full_build/bin/ffmpeg.exe",
+                ],
+                "macosx.*": [
+                    "--browsertime-node",
+                    "$MOZ_FETCHES_DIR/node/bin/node",
+                    "--browsertime-geckodriver",
+                    "$MOZ_FETCHES_DIR/geckodriver",
+                    "--browsertime-chromedriver",
+                    "$MOZ_FETCHES_DIR/" + cd_extracted_name["mac"],
+                    "--browsertime-ffmpeg",
+                    "$MOZ_FETCHES_DIR/ffmpeg-macos/ffmpeg",
+                ],
+                "default": [
+                    "--browsertime-node",
+                    "$MOZ_FETCHES_DIR/node/bin/node",
+                    "--browsertime-geckodriver",
+                    "$MOZ_FETCHES_DIR/geckodriver",
+                    "--browsertime-chromedriver",
+                    "$MOZ_FETCHES_DIR/" + cd_extracted_name["default"],
+                    "--browsertime-ffmpeg",
+                    "$MOZ_FETCHES_DIR/ffmpeg-4.4.1-i686-static/ffmpeg",
+                ],
+            }
+        }
+
+        extra_options.extend(evaluate_keyed_by(eos, "mozharness.extra-options", task))
+
+        yield task
+
+
+def get_mobile_project(task):
+    """Returns the mobile project of the specified task or None."""
+
+    if not task["build-platform"].startswith("android"):
+        return
+
+    mobile_projects = ("fenix", "geckoview", "refbrow", "chrome-m")
+
+    for name in mobile_projects:
+        if name in task["test-name"]:
+            return name
+
+    target = None
+    if "target" in task:
+        resolve_keyed_by(
+            task, "target", item_name=task["test-name"], enforce_single_match=False
+        )
+        target = task["target"]
+    if target:
+        if isinstance(target, dict):
+            target = target["name"]
+
+        for name in mobile_projects:
+            if name in target:
+                return name
+
+    return None
+
+
+@transforms.add
+def disable_wpt_timeouts_on_autoland(config, tasks):
+    """do not run web-platform-tests that are expected TIMEOUT on autoland"""
+    for task in tasks:
+        if (
+            "web-platform-tests" in task["test-name"]
+            and config.params["project"] == "autoland"
+        ):
+            task["mozharness"].setdefault("extra-options", []).append("--skip-timeout")
+        yield task
+
+
+@transforms.add
+def enable_code_coverage(config, tasks):
+    """Enable code coverage for the ccov build-platforms"""
+    for task in tasks:
+        if "ccov" in task["build-platform"]:
+            # Do not run tests on fuzzing builds
+            if "fuzzing" in task["build-platform"]:
+                task["run-on-projects"] = []
+                continue
+
+            # Skip this transform for android code coverage builds.
+            if "android" in task["build-platform"]:
+                task.setdefault("fetches", {}).setdefault("toolchain", []).append(
+                    "linux64-grcov"
+                )
+                task["mozharness"].setdefault("extra-options", []).append(
+                    "--java-code-coverage"
+                )
+                yield task
+                continue
+            task["mozharness"].setdefault("extra-options", []).append("--code-coverage")
+            task["instance-size"] = "xlarge"
+
+            # Temporarily disable Mac tests on mozilla-central
+            if "mac" in task["build-platform"]:
+                task["run-on-projects"] = []
+
+            # Ensure we always run on the projects defined by the build, unless the test
+            # is try only or shouldn't run at all.
+            if task["run-on-projects"] not in [[]]:
+                task["run-on-projects"] = "built-projects"
+
+            # Ensure we don't optimize test suites out.
+            # We always want to run all test suites for coverage purposes.
+            task.pop("schedules-component", None)
+            task.pop("when", None)
+            task["optimization"] = None
+
+            # Add a toolchain and a fetch task for the grcov binary.
+            if any(p in task["build-platform"] for p in ("linux", "osx", "win")):
+                task.setdefault("fetches", {})
+                task["fetches"].setdefault("fetch", [])
+                task["fetches"].setdefault("toolchain", [])
+                task["fetches"].setdefault("build", [])
+
+            if "linux" in task["build-platform"]:
+                task["fetches"]["toolchain"].append("linux64-grcov")
+            elif "osx" in task["build-platform"]:
+                task["fetches"]["toolchain"].append("macosx64-grcov")
+            elif "win" in task["build-platform"]:
+                task["fetches"]["toolchain"].append("win64-grcov")
+
+            task["fetches"]["build"].append({"artifact": "target.mozinfo.json"})
+
+            if "talos" in task["test-name"]:
+                task["max-run-time"] = 7200
+                if "linux" in task["build-platform"]:
+                    task["docker-image"] = {"in-tree": "ubuntu1804-test"}
+                task["mozharness"]["extra-options"].append("--add-option")
+                task["mozharness"]["extra-options"].append("--cycles,1")
+                task["mozharness"]["extra-options"].append("--add-option")
+                task["mozharness"]["extra-options"].append("--tppagecycles,1")
+                task["mozharness"]["extra-options"].append("--add-option")
+                task["mozharness"]["extra-options"].append("--no-upload-results")
+                task["mozharness"]["extra-options"].append("--add-option")
+                task["mozharness"]["extra-options"].append("--tptimeout,15000")
+            if "raptor" in task["test-name"]:
+                task["max-run-time"] = 1800
+        yield task
+
+
+@transforms.add
+def handle_run_on_projects(config, tasks):
+    """Handle translating `built-projects` appropriately"""
+    for task in tasks:
+        if task["run-on-projects"] == "built-projects":
+            task["run-on-projects"] = task["build-attributes"].get(
+                "run_on_projects", ["all"]
+            )
+
+        if task.pop("built-projects-only", False):
+            built_projects = set(
+                task["build-attributes"].get("run_on_projects", {"all"})
+            )
+            run_on_projects = set(task.get("run-on-projects", set()))
+
+            # If 'all' exists in run-on-projects, then the intersection of both
+            # is built-projects. Similarly if 'all' exists in built-projects,
+            # the intersection is run-on-projects (so do nothing). When neither
+            # contains 'all', take the actual set intersection.
+            if "all" in run_on_projects:
+                task["run-on-projects"] = sorted(built_projects)
+            elif "all" not in built_projects:
+                task["run-on-projects"] = sorted(run_on_projects & built_projects)
+        yield task
+
+
+@transforms.add
+def handle_tier(config, tasks):
+    """Set the tier based on policy for all test descriptions that do not
+    specify a tier otherwise."""
+    for task in tasks:
+        if "tier" in task:
+            resolve_keyed_by(
+                task,
+                "tier",
+                item_name=task["test-name"],
+                variant=task["attributes"].get("unittest_variant"),
+                enforce_single_match=False,
+            )
+
+        # only override if not set for the test
+        if "tier" not in task or task["tier"] == "default":
+            if task["test-platform"] in [
+                "linux64/opt",
+                "linux64/debug",
+                "linux64-shippable/opt",
+                "linux64-devedition/opt",
+                "linux64-asan/opt",
+                "linux64-qr/opt",
+                "linux64-qr/debug",
+                "linux64-shippable-qr/opt",
+                "linux1804-64/opt",
+                "linux1804-64/debug",
+                "linux1804-64-shippable/opt",
+                "linux1804-64-devedition/opt",
+                "linux1804-64-qr/opt",
+                "linux1804-64-qr/debug",
+                "linux1804-64-shippable-qr/opt",
+                "linux1804-64-asan-qr/opt",
+                "linux1804-64-tsan-qr/opt",
+                "windows7-32-qr/debug",
+                "windows7-32-qr/opt",
+                "windows7-32-devedition-qr/opt",
+                "windows7-32-shippable-qr/opt",
+                "windows10-32-qr/debug",
+                "windows10-32-qr/opt",
+                "windows10-32-shippable-qr/opt",
+                "windows10-32-2004-qr/debug",
+                "windows10-32-2004-qr/opt",
+                "windows10-32-2004-shippable-qr/opt",
+                "windows10-aarch64-qr/opt",
+                "windows10-64/debug",
+                "windows10-64/opt",
+                "windows10-64-shippable/opt",
+                "windows10-64-devedition/opt",
+                "windows10-64-qr/opt",
+                "windows10-64-qr/debug",
+                "windows10-64-shippable-qr/opt",
+                "windows10-64-devedition-qr/opt",
+                "windows10-64-asan-qr/opt",
+                "windows10-64-2004-qr/opt",
+                "windows10-64-2004-qr/debug",
+                "windows10-64-2004-shippable-qr/opt",
+                "windows10-64-2004-devedition-qr/opt",
+                "windows10-64-2004-asan-qr/opt",
+                "windows11-32-2009-qr/debug",
+                "windows11-32-2009-qr/opt",
+                "windows11-32-2009-shippable-qr/opt",
+                "windows11-64-2009-qr/opt",
+                "windows11-64-2009-qr/debug",
+                "windows11-64-2009-shippable-qr/opt",
+                "windows11-64-2009-devedition-qr/opt",
+                "windows11-64-2009-asan-qr/opt",
+                "macosx1015-64/opt",
+                "macosx1015-64/debug",
+                "macosx1015-64-shippable/opt",
+                "macosx1015-64-devedition/opt",
+                "macosx1015-64-devedition-qr/opt",
+                "macosx1015-64-qr/opt",
+                "macosx1015-64-shippable-qr/opt",
+                "macosx1015-64-qr/debug",
+                "macosx1100-64-shippable-qr/opt",
+                "macosx1100-64-qr/debug",
+                "android-em-7.0-x86_64-shippable/opt",
+                "android-em-7.0-x86_64-shippable-lite/opt",
+                "android-em-7.0-x86_64/debug",
+                "android-em-7.0-x86_64/debug-isolated-process",
+                "android-em-7.0-x86_64/opt",
+                "android-em-7.0-x86_64-lite/opt",
+                "android-em-7.0-x86-shippable/opt",
+                "android-em-7.0-x86-shippable-lite/opt",
+                "android-em-7.0-x86_64-shippable-qr/opt",
+                "android-em-7.0-x86_64-qr/debug",
+                "android-em-7.0-x86_64-qr/debug-isolated-process",
+                "android-em-7.0-x86_64-qr/opt",
+                "android-em-7.0-x86_64-shippable-lite-qr/opt",
+                "android-em-7.0-x86_64-lite-qr/debug",
+                "android-em-7.0-x86_64-lite-qr/opt",
+            ]:
+                task["tier"] = 1
+            else:
+                task["tier"] = 2
+
+        yield task
+
+
+@transforms.add
+def apply_raptor_tier_optimization(config, tasks):
+    for task in tasks:
+        if task["suite"] != "raptor":
+            yield task
+            continue
+
+        if "regression-tests" in task["test-name"]:
+            # Don't optimize the regression tests
+            yield task
+            continue
+
+        if not task["test-platform"].startswith("android-hw"):
+            task["optimization"] = {"skip-unless-expanded": None}
+            if task["tier"] > 1:
+                task["optimization"] = {"skip-unless-backstop": None}
+
+        if task["attributes"].get("unittest_variant"):
+            task["tier"] = max(task["tier"], 2)
+        yield task
+
+
+@transforms.add
+def disable_try_only_platforms(config, tasks):
+    """Turns off platforms that should only run on try."""
+    try_only_platforms = ()
+    for task in tasks:
+        if any(re.match(k + "$", task["test-platform"]) for k in try_only_platforms):
+            task["run-on-projects"] = []
+        yield task
+
+
+@transforms.add
+def ensure_spi_disabled_on_all_but_spi(config, tasks):
+    for task in tasks:
+        variant = task["attributes"].get("unittest_variant", "")
+        has_no_setpref = ("gtest", "cppunit", "jittest", "junit", "raptor")
+
+        if (
+            all(s not in task["suite"] for s in has_no_setpref)
+            and "socketprocess" not in variant
+        ):
+            task["mozharness"]["extra-options"].append(
+                "--setpref=media.peerconnection.mtransport_process=false"
+            )
+            task["mozharness"]["extra-options"].append(
+                "--setpref=network.process.enabled=false"
+            )
+
+        yield task
+
+
+test_setting_description_schema = Schema(
+    {
+        Required("_hash"): str,
+        "platform": {
+            Required("arch"): Any("32", "64", "aarch64", "arm7", "x86_64"),
+            Required("os"): {
+                Required("name"): Any("android", "linux", "macosx", "windows"),
+                Required("version"): str,
+                Optional("build"): str,
+            },
+            Optional("device"): str,
+            Optional("display"): "wayland",
+            Optional("machine"): Any("ref-hw-2017"),
+        },
+        "build": {
+            Required("type"): Any("opt", "debug", "debug-isolated-process"),
+            Any(
+                "asan",
+                "ccov",
+                "clang-trunk",
+                "devedition",
+                "domstreams",
+                "lite",
+                "mingwclang",
+                "nightlyasrelease",
+                "shippable",
+                "tsan",
+            ): bool,
+        },
+        "runtime": {Any(*list(TEST_VARIANTS.keys()) + ["1proc"]): bool},
+    },
+    check=False,
+)
+"""Schema test settings must conform to. Validated by
+:py:func:`~test.test_mozilla_central.test_test_setting`"""
+
+
+@transforms.add
+def set_test_setting(config, tasks):
+    """A test ``setting`` is the set of configuration that uniquely
+    distinguishes a test task from other tasks that run the same suite
+    (ignoring chunks).
+
+    There are three different types of information that make up a setting:
+
+    1. Platform - Information describing the underlying platform tests run on,
+    e.g, OS, CPU architecture, etc.
+
+    2. Build - Information describing the build being tested, e.g build type,
+    ccov, asan/tsan, etc.
+
+    3. Runtime - Information describing which runtime parameters are enabled,
+    e.g, prefs, environment variables, etc.
+
+    This transform adds a ``test-setting`` object to the ``extra`` portion of
+    all test tasks, of the form:
+
+    .. code-block::
+
+        {
+            "platform": { ... },
+            "build": { ... },
+            "runtime": { ... }
+        }
+
+    This information could be derived from the label, but consuming this
+    object is less brittle.
+    """
+    # Some attributes have a dash in them which complicates parsing. Ensure we
+    # don't split them up.
+    # TODO Rename these so they don't have a dash.
+    dash_attrs = [
+        "clang-trunk",
+        "ref-hw-2017",
+    ]
+    dash_token = "%D%"
+    platform_re = re.compile(r"(\D+)(\d*)")
+
+    for task in tasks:
+        setting = {
+            "platform": {
+                "os": {},
+            },
+            "build": {},
+            "runtime": {},
+        }
+
+        # parse platform and build information out of 'test-platform'
+        platform, build_type = task["test-platform"].split("/", 1)
+
+        # ensure dashed attributes don't get split up
+        for attr in dash_attrs:
+            if attr in platform:
+                platform = platform.replace(attr, attr.replace("-", dash_token))
+
+        parts = platform.split("-")
+
+        # restore dashes now that split is finished
+        for i, part in enumerate(parts):
+            if dash_token in part:
+                parts[i] = part.replace(dash_token, "-")
+
+        match = platform_re.match(parts.pop(0))
+        assert match
+        os_name, os_version = match.groups()
+
+        device = machine = os_build = display = None
+        if os_name == "android":
+            device = parts.pop(0)
+            if device == "hw":
+                device = parts.pop(0)
+            else:
+                device = "emulator"
+
+            os_version = parts.pop(0)
+            if parts[0].isdigit():
+                os_version = f"{os_version}.{parts.pop(0)}"
+
+            if parts[0] == "android":
+                parts.pop(0)
+
+            arch = parts.pop(0)
+
+        else:
+            arch = parts.pop(0)
+            if parts[0].isdigit():
+                os_build = parts.pop(0)
+
+            if parts[0] == "ref-hw-2017":
+                machine = parts.pop(0)
+
+            if parts[0] == "wayland":
+                display = parts.pop(0)
+
+        # It's not always possible to glean the exact architecture used from
+        # the task, so sometimes this will just be set to "32" or "64".
+        setting["platform"]["arch"] = arch
+        setting["platform"]["os"] = {
+            "name": os_name,
+            "version": os_version,
+        }
+
+        if os_build:
+            setting["platform"]["os"]["build"] = os_build
+
+        if device:
+            setting["platform"]["device"] = device
+
+        if machine:
+            setting["platform"]["machine"] = machine
+
+        if display:
+            setting["platform"]["display"] = display
+
+        # parse remaining parts as build attributes
+        setting["build"]["type"] = build_type
+        while parts:
+            attr = parts.pop(0)
+            if attr == "qr":
+                # all tasks are webrender now, no need to store it
+                continue
+
+            setting["build"][attr] = True
+
+        unittest_variant = task["attributes"].get("unittest_variant")
+        if unittest_variant:
+            for variant in unittest_variant.split("+"):
+                setting["runtime"][variant] = True
+
+        # add a hash of the setting object for easy comparisons
+        setting["_hash"] = hashlib.sha256(
+            json.dumps(setting, sort_keys=True).encode("utf-8")
+        ).hexdigest()[:12]
+
+        task["test-setting"] = ReadOnlyDict(**setting)
+        yield task
+
+
+@transforms.add
+def allow_software_gl_layers(config, tasks):
+    """
+    Handle the "allow-software-gl-layers" property for platforms where it
+    applies.
+    """
+    for task in tasks:
+        if task.get("allow-software-gl-layers"):
+            # This should be set always once bug 1296086 is resolved.
+            task["mozharness"].setdefault("extra-options", []).append(
+                "--allow-software-gl-layers"
+            )
+
+        yield task
+
+
+@transforms.add
+def enable_webrender(config, tasks):
+    """
+    Handle the "webrender" property by passing a flag to mozharness if it is
+    enabled.
+    """
+    for task in tasks:
+        # TODO: this was all conditionally in enable_webrender- do we still need this?
+        extra_options = task["mozharness"].setdefault("extra-options", [])
+        # We only want to 'setpref' on tests that have a profile
+        if not task["attributes"]["unittest_category"] in [
+            "cppunittest",
+            "geckoview-junit",
+            "gtest",
+            "jittest",
+            "raptor",
+        ]:
+            extra_options.append("--setpref=layers.d3d11.enable-blacklist=false")
+
+        yield task
+
+
+@transforms.add
+def set_schedules_for_webrender_android(config, tasks):
+    """android-hw has limited resources, we need webrender on phones"""
+    for task in tasks:
+        if task["suite"] in ["crashtest", "reftest"] and task[
+            "test-platform"
+        ].startswith("android-hw"):
+            task["schedules-component"] = "android-hw-gfx"
+        yield task
+
+
+@transforms.add
+def set_retry_exit_status(config, tasks):
+    """Set the retry exit status to TBPL_RETRY, the value returned by mozharness
+    scripts to indicate a transient failure that should be retried."""
+    for task in tasks:
+        # add in 137 as it is an error with GCP workers
+        task["retry-exit-status"] = [4, 137]
+        yield task
+
+
+@transforms.add
+def set_profile(config, tasks):
+    """Set profiling mode for tests."""
+    ttconfig = config.params["try_task_config"]
+    profile = ttconfig.get("gecko-profile", False)
+    settings = (
+        "gecko-profile-interval",
+        "gecko-profile-entries",
+        "gecko-profile-threads",
+        "gecko-profile-features",
+    )
+
+    for task in tasks:
+        if profile and task["suite"] in ["talos", "raptor"]:
+            extras = task["mozharness"]["extra-options"]
+            extras.append("--gecko-profile")
+            for setting in settings:
+                value = ttconfig.get(setting)
+                if value is not None:
+                    # These values can contain spaces (eg the "DOM Worker"
+                    # thread) and the command is constructed in different,
+                    # incompatible ways on different platforms.
+
+                    if task["test-platform"].startswith("win"):
+                        # Double quotes for Windows (single won't work).
+                        extras.append("--" + setting + '="' + str(value) + '"')
+                    else:
+                        # Other platforms keep things as separate values,
+                        # rather than joining with spaces.
+                        extras.append("--" + setting + "=" + str(value))
+
+        yield task
+
+
+@transforms.add
+def set_tag(config, tasks):
+    """Set test for a specific tag."""
+    tag = None
+    if config.params["try_mode"] == "try_option_syntax":
+        tag = config.params["try_options"]["tag"]
+    for task in tasks:
+        if tag:
+            task["mozharness"]["extra-options"].extend(["--tag", tag])
+        yield task
+
+
+@transforms.add
+def set_test_type(config, tasks):
+    types = ["mochitest", "reftest", "talos", "raptor", "geckoview-junit", "gtest"]
+    for task in tasks:
+        for test_type in types:
+            if test_type in task["suite"] and "web-platform" not in task["suite"]:
+                task.setdefault("tags", {})["test-type"] = test_type
+        yield task
+
+
+@transforms.add
+def set_schedules_components(config, tasks):
+    for task in tasks:
+        if "optimization" in task or "when" in task:
+            yield task
+            continue
+
+        category = task["attributes"]["unittest_category"]
+        schedules = task.get("schedules-component", category)
+        if isinstance(schedules, str):
+            schedules = [schedules]
+
+        schedules = set(schedules)
+        if schedules & set(INCLUSIVE_COMPONENTS):
+            # if this is an "inclusive" test, then all files which might
+            # cause it to run are annotated with SCHEDULES in moz.build,
+            # so do not include the platform or any other components here
+            task["schedules-component"] = sorted(schedules)
+            yield task
+            continue
+
+        schedules.add(category)
+        schedules.add(platform_family(task["build-platform"]))
+
+        task["schedules-component"] = sorted(schedules)
+        yield task
+
+
+@transforms.add
+def enable_parallel_marking_in_tsan_tests(config, tasks):
+    """Enable parallel marking in TSAN tests"""
+    skip_list = ["cppunittest", "gtest"]
+    for task in tasks:
+        if "-tsan-" in task["test-platform"]:
+            if task["suite"] not in skip_list:
+                extra_options = task["mozharness"].setdefault("extra-options", [])
+                extra_options.append(
+                    "--setpref=javascript.options.mem.gc_parallel_marking=true"
+                )
+
+        yield task
+
+
+@transforms.add
+def apply_windows7_optimization(config, tasks):
+    for task in tasks:
+        if task["test-platform"].startswith("windows7"):
+            task["optimization"] = {"skip-unless-backstop": None}
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/test/raptor.py b/taskcluster/gecko_taskgraph/transforms/test/raptor.py
new file mode 100644
index 0000000000..3eac5dd9ef
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/raptor.py
@@ -0,0 +1,317 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by
+from taskgraph.util.treeherder import join_symbol, split_symbol
+from voluptuous import Extra, Optional, Required
+
+from gecko_taskgraph.transforms.test import test_description_schema
+from gecko_taskgraph.util.copy_task import copy_task
+
+transforms = TransformSequence()
+task_transforms = TransformSequence()
+
+raptor_description_schema = Schema(
+    {
+        # Raptor specific configs.
+        Optional("raptor"): {
+            Optional("activity"): optionally_keyed_by("app", str),
+            Optional("apps"): optionally_keyed_by("test-platform", "subtest", [str]),
+            Optional("binary-path"): optionally_keyed_by("app", str),
+            Optional("run-visual-metrics"): optionally_keyed_by("app", bool),
+            Optional("subtests"): optionally_keyed_by("app", "test-platform", list),
+            Optional("test"): str,
+            Optional("test-url-param"): optionally_keyed_by(
+                "subtest", "test-platform", str
+            ),
+        },
+        # Configs defined in the 'test_description_schema'.
+        Optional("max-run-time"): optionally_keyed_by(
+            "app", "subtest", "test-platform", test_description_schema["max-run-time"]
+        ),
+        Optional("run-on-projects"): optionally_keyed_by(
+            "app",
+            "test-name",
+            "raptor.test",
+            "subtest",
+            "variant",
+            test_description_schema["run-on-projects"],
+        ),
+        Optional("variants"): test_description_schema["variants"],
+        Optional("target"): optionally_keyed_by(
+            "app", test_description_schema["target"]
+        ),
+        Optional("tier"): optionally_keyed_by(
+            "app", "raptor.test", "subtest", "variant", test_description_schema["tier"]
+        ),
+        Required("test-name"): test_description_schema["test-name"],
+        Required("test-platform"): test_description_schema["test-platform"],
+        Required("require-signed-extensions"): test_description_schema[
+            "require-signed-extensions"
+        ],
+        Required("treeherder-symbol"): test_description_schema["treeherder-symbol"],
+        # Any unrecognized keys will be validated against the test_description_schema.
+        Extra: object,
+    }
+)
+
+transforms.add_validate(raptor_description_schema)
+
+
+@transforms.add
+def set_defaults(config, tests):
+    for test in tests:
+        test.setdefault("raptor", {}).setdefault("run-visual-metrics", False)
+        yield test
+
+
+@transforms.add
+def split_apps(config, tests):
+    app_symbols = {
+        "chrome": "ChR",
+        "chrome-m": "ChR",
+        "chromium": "Cr",
+        "fenix": "fenix",
+        "refbrow": "refbrow",
+        "safari": "Saf",
+        "custom-car": "CaR",
+    }
+
+    for test in tests:
+        apps = test["raptor"].pop("apps", None)
+        if not apps:
+            yield test
+            continue
+
+        for app in apps:
+            # Ignore variants for non-Firefox or non-mobile applications.
+            if app not in ["firefox", "geckoview", "fenix", "chrome-m"] and test[
+                "attributes"
+            ].get("unittest_variant"):
+                continue
+
+            atest = copy_task(test)
+            suffix = f"-{app}"
+            atest["app"] = app
+            atest["description"] += f" on {app.capitalize()}"
+
+            name = atest["test-name"] + suffix
+            atest["test-name"] = name
+            atest["try-name"] = name
+
+            if app in app_symbols:
+                group, symbol = split_symbol(atest["treeherder-symbol"])
+                group += f"-{app_symbols[app]}"
+                atest["treeherder-symbol"] = join_symbol(group, symbol)
+
+            yield atest
+
+
+@transforms.add
+def handle_keyed_by_prereqs(config, tests):
+    """
+    Only resolve keys for prerequisite fields here since the
+    these keyed-by options might have keyed-by fields
+    as well.
+    """
+    for test in tests:
+        resolve_keyed_by(test, "raptor.subtests", item_name=test["test-name"])
+        yield test
+
+
+@transforms.add
+def split_raptor_subtests(config, tests):
+    for test in tests:
+        # For tests that have 'subtests' listed, we want to create a separate
+        # test job for every subtest (i.e. split out each page-load URL into its own job)
+        subtests = test["raptor"].pop("subtests", None)
+        if not subtests:
+            yield test
+            continue
+
+        for chunk_number, subtest in enumerate(subtests):
+
+            # Create new test job
+            chunked = copy_task(test)
+            chunked["chunk-number"] = 1 + chunk_number
+            chunked["subtest"] = subtest
+            chunked["subtest-symbol"] = subtest
+            if isinstance(chunked["subtest"], list):
+                chunked["subtest"] = subtest[0]
+                chunked["subtest-symbol"] = subtest[1]
+            chunked = resolve_keyed_by(
+                chunked, "tier", chunked["subtest"], defer=["variant"]
+            )
+            yield chunked
+
+
+@transforms.add
+def handle_keyed_by(config, tests):
+    fields = [
+        "raptor.test-url-param",
+        "raptor.run-visual-metrics",
+        "raptor.activity",
+        "raptor.binary-path",
+        "limit-platforms",
+        "fetches.fetch",
+        "max-run-time",
+        "run-on-projects",
+        "target",
+        "tier",
+    ]
+    for test in tests:
+        for field in fields:
+            resolve_keyed_by(
+                test, field, item_name=test["test-name"], defer=["variant"]
+            )
+        yield test
+
+
+@transforms.add
+def split_page_load_by_url(config, tests):
+    for test in tests:
+        # `chunk-number` and 'subtest' only exists when the task had a
+        # definition for `subtests`
+        chunk_number = test.pop("chunk-number", None)
+        subtest = test.get(
+            "subtest"
+        )  # don't pop as some tasks need this value after splitting variants
+        subtest_symbol = test.pop("subtest-symbol", None)
+
+        if not chunk_number or not subtest:
+            yield test
+            continue
+
+        if len(subtest_symbol) > 10 and "ytp" not in subtest_symbol:
+            raise Exception(
+                "Treeherder symbol %s is larger than 10 char! Please use a different symbol."
+                % subtest_symbol
+            )
+
+        if test["test-name"].startswith("browsertime-"):
+            test["raptor"]["test"] = subtest
+
+            # Remove youtube-playback in the test name to avoid duplication
+            test["test-name"] = test["test-name"].replace("youtube-playback-", "")
+        else:
+            # Use full test name if running on webextension
+            test["raptor"]["test"] = "raptor-tp6-" + subtest + "-{}".format(test["app"])
+
+        # Only run the subtest/single URL
+        test["test-name"] += f"-{subtest}"
+        test["try-name"] += f"-{subtest}"
+
+        # Set treeherder symbol and description
+        group, _ = split_symbol(test["treeherder-symbol"])
+        test["treeherder-symbol"] = join_symbol(group, subtest_symbol)
+        test["description"] += f" on {subtest}"
+
+        yield test
+
+
+@transforms.add
+def modify_extra_options(config, tests):
+    for test in tests:
+        test_name = test.get("test-name", None)
+
+        if "first-install" in test_name:
+            # First-install tests should never use conditioned profiles
+            extra_options = test.setdefault("mozharness", {}).setdefault(
+                "extra-options", []
+            )
+
+            for i, opt in enumerate(extra_options):
+                if "conditioned-profile" in opt:
+                    if i:
+                        extra_options.pop(i)
+                    break
+
+        if "-widevine" in test_name:
+            extra_options = test.setdefault("mozharness", {}).setdefault(
+                "extra-options", []
+            )
+            for i, opt in enumerate(extra_options):
+                if "--conditioned-profile=settled" in opt:
+                    if i:
+                        extra_options[i] += "-youtube"
+                    break
+
+        if "unity-webgl" in test_name:
+            # Disable the extra-profiler-run for unity-webgl tests.
+            extra_options = test.setdefault("mozharness", {}).setdefault(
+                "extra-options", []
+            )
+            for i, opt in enumerate(extra_options):
+                if "extra-profiler-run" in opt:
+                    if i:
+                        extra_options.pop(i)
+                    break
+
+        yield test
+
+
+@transforms.add
+def add_extra_options(config, tests):
+    for test in tests:
+        mozharness = test.setdefault("mozharness", {})
+        if test.get("app", "") == "chrome-m":
+            mozharness["tooltool-downloads"] = "internal"
+
+        extra_options = mozharness.setdefault("extra-options", [])
+
+        # Adding device name if we're on android
+        test_platform = test["test-platform"]
+        if test_platform.startswith("android-hw-g5"):
+            extra_options.append("--device-name=g5")
+        elif test_platform.startswith("android-hw-a51"):
+            extra_options.append("--device-name=a51")
+        elif test_platform.startswith("android-hw-p5"):
+            extra_options.append("--device-name=p5_aarch64")
+
+        if test["raptor"].pop("run-visual-metrics", False):
+            extra_options.append("--browsertime-video")
+            extra_options.append("--browsertime-visualmetrics")
+            test["attributes"]["run-visual-metrics"] = True
+
+        if "app" in test:
+            extra_options.append(
+                "--app={}".format(test["app"])
+            )  # don't pop as some tasks need this value after splitting variants
+
+        if "activity" in test["raptor"]:
+            extra_options.append("--activity={}".format(test["raptor"].pop("activity")))
+
+        if "binary-path" in test["raptor"]:
+            extra_options.append(
+                "--binary-path={}".format(test["raptor"].pop("binary-path"))
+            )
+
+        if "test" in test["raptor"]:
+            extra_options.append("--test={}".format(test["raptor"].pop("test")))
+
+        if test["require-signed-extensions"]:
+            extra_options.append("--is-release-build")
+
+        if "test-url-param" in test["raptor"]:
+            param = test["raptor"].pop("test-url-param")
+            if not param == []:
+                extra_options.append(
+                    "--test-url-params={}".format(param.replace(" ", ""))
+                )
+
+        extra_options.append("--project={}".format(config.params.get("project")))
+
+        yield test
+
+
+@task_transforms.add
+def add_scopes_and_proxy(config, tasks):
+    for task in tasks:
+        task.setdefault("worker", {})["taskcluster-proxy"] = True
+        task.setdefault("scopes", []).append(
+            "secrets:get:project/perftest/gecko/level-{level}/perftest-login"
+        )
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/test/variant.py b/taskcluster/gecko_taskgraph/transforms/test/variant.py
new file mode 100644
index 0000000000..e2fd9764e1
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/variant.py
@@ -0,0 +1,128 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+import datetime
+
+import jsone
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import Schema, validate_schema
+from taskgraph.util.treeherder import join_symbol, split_symbol
+from taskgraph.util.yaml import load_yaml
+from voluptuous import Any, Optional, Required
+
+import gecko_taskgraph
+from gecko_taskgraph.util.copy_task import copy_task
+from gecko_taskgraph.util.templates import merge
+
+transforms = TransformSequence()
+
+TEST_VARIANTS = load_yaml(
+    gecko_taskgraph.GECKO, "taskcluster", "ci", "test", "variants.yml"
+)
+"""List of available test variants defined."""
+
+
+variant_description_schema = Schema(
+    {
+        str: {
+            Required("description"): str,
+            Required("suffix"): str,
+            Required("component"): str,
+            Required("expiration"): str,
+            Optional("when"): {Any("$eval", "$if"): str},
+            Optional("replace"): {str: object},
+            Optional("merge"): {str: object},
+        }
+    }
+)
+"""variant description schema"""
+
+
+@transforms.add
+def split_variants(config, tasks):
+    """Splits test definitions into multiple tasks based on the `variants` key.
+
+    If `variants` are defined, the original task will be yielded along with a
+    copy of the original task for each variant defined in the list. The copies
+    will have the 'unittest_variant' attribute set.
+    """
+    validate_schema(variant_description_schema, TEST_VARIANTS, "In variants.yml:")
+
+    def find_expired_variants(variants):
+        expired = []
+
+        # do not expire on esr/beta/release
+        if config.params.get("release_type", "") in [
+            "release",
+            "beta",
+        ]:
+            return []
+
+        if "esr" in config.params.get("release_type", ""):
+            return []
+
+        today = datetime.datetime.today()
+        for variant in variants:
+
+            expiration = variants[variant]["expiration"]
+            if len(expiration.split("-")) == 1:
+                continue
+            expires_at = datetime.datetime.strptime(expiration, "%Y-%m-%d")
+            if expires_at < today:
+                expired.append(variant)
+        return expired
+
+    def remove_expired(variants, expired):
+        remaining_variants = []
+        for name in variants:
+            parts = [p for p in name.split("+") if p not in expired]
+            if len(parts) == 0:
+                continue
+
+            remaining_variants.append(name)
+        return remaining_variants
+
+    def apply_variant(variant, task):
+        task["description"] = variant["description"].format(**task)
+
+        suffix = f"-{variant['suffix']}"
+        group, symbol = split_symbol(task["treeherder-symbol"])
+        if group != "?":
+            group += suffix
+        else:
+            symbol += suffix
+        task["treeherder-symbol"] = join_symbol(group, symbol)
+
+        # This will be used to set the label and try-name in 'make_job_description'.
+        task.setdefault("variant-suffix", "")
+        task["variant-suffix"] += suffix
+
+        # Replace and/or merge the configuration.
+        task.update(variant.get("replace", {}))
+        return merge(task, variant.get("merge", {}))
+
+    expired_variants = find_expired_variants(TEST_VARIANTS)
+    for task in tasks:
+        variants = task.pop("variants", [])
+        variants = remove_expired(variants, expired_variants)
+
+        if task.pop("run-without-variant"):
+            yield copy_task(task)
+
+        for name in variants:
+            # Apply composite variants (joined by '+') in order.
+            parts = name.split("+")
+            taskv = copy_task(task)
+            for part in parts:
+                variant = TEST_VARIANTS[part]
+
+                # If any variant in a composite fails this check we skip it.
+                if "when" in variant:
+                    context = {"task": task}
+                    if not jsone.render(variant["when"], context):
+                        break
+
+                taskv = apply_variant(variant, taskv)
+            else:
+                taskv["attributes"]["unittest_variant"] = name
+                yield taskv
diff --git a/taskcluster/gecko_taskgraph/transforms/test/worker.py b/taskcluster/gecko_taskgraph/transforms/test/worker.py
new file mode 100644
index 0000000000..0d8d72162d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/test/worker.py
@@ -0,0 +1,201 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+# default worker types keyed by instance-size
+LINUX_WORKER_TYPES = {
+    "large": "t-linux-large",
+    "xlarge": "t-linux-xlarge",
+    "default": "t-linux-large",
+}
+
+# windows worker types keyed by test-platform and virtualization
+WINDOWS_WORKER_TYPES = {
+    "windows7-32-qr": {
+        "virtual": "t-win7-32",
+        "virtual-with-gpu": "t-win7-32-gpu",
+        "hardware": "t-win10-64-1803-hw",
+    },
+    "windows7-32-shippable-qr": {
+        "virtual": "t-win7-32",
+        "virtual-with-gpu": "t-win7-32-gpu",
+        "hardware": "t-win10-64-1803-hw",
+    },
+    "windows7-32-devedition-qr": {  # build only, tests have no value
+        "virtual": "t-win7-32",
+        "virtual-with-gpu": "t-win7-32-gpu",
+        "hardware": "t-win10-64-1803-hw",
+    },
+    "windows10-64": {  # source-test
+        "virtual": "t-win10-64",
+        "virtual-with-gpu": "t-win10-64-gpu-s",
+        "hardware": "t-win10-64-1803-hw",
+    },
+    "windows10-64-shippable-qr": {
+        "virtual": "t-win10-64",
+        "virtual-with-gpu": "t-win10-64-gpu-s",
+        "hardware": "t-win10-64-1803-hw",
+    },
+    "windows10-64-ref-hw-2017": {
+        "virtual": "t-win10-64",
+        "virtual-with-gpu": "t-win10-64-gpu-s",
+        "hardware": "t-win10-64-ref-hw",
+    },
+    "windows10-64-2009-qr": {
+        "virtual": "win10-64-2009",
+        "virtual-with-gpu": "win10-64-2009-gpu",
+    },
+    "windows10-64-2009-shippable-qr": {
+        "virtual": "win10-64-2009",
+        "virtual-with-gpu": "win10-64-2009-gpu",
+    },
+    "windows11-32-2009-mingwclang-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-32-2009-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-32-2009-shippable-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-ccov": {
+        "virtual": "win11-64-2009-ssd",
+        "virtual-with-gpu": "win11-64-2009-ssd-gpu",
+    },
+    "windows11-64-2009-ccov-qr": {
+        "virtual": "win11-64-2009-ssd",
+        "virtual-with-gpu": "win11-64-2009-ssd-gpu",
+    },
+    "windows11-64-2009-devedition": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-shippable": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-shippable-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-devedition-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-asan-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+    "windows11-64-2009-mingwclang-qr": {
+        "virtual": "win11-64-2009",
+        "virtual-with-gpu": "win11-64-2009-gpu",
+    },
+}
+
+# os x worker types keyed by test-platform
+MACOSX_WORKER_TYPES = {
+    "macosx1015-64-power": "t-osx-1015-power",
+    "macosx1015-64": "t-osx-1015-r8",
+    "macosx1100-64": "t-osx-1100-m1",
+}
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_worker_type(config, tasks):
+    """Set the worker type based on the test platform."""
+    for task in tasks:
+        # during the taskcluster migration, this is a bit tortured, but it
+        # will get simpler eventually!
+        test_platform = task["test-platform"]
+        if task.get("worker-type", "default") != "default":
+            # This test already has its worker type defined, so just use that (yields below)
+            # Unless the value is set to "default", in that case ignore it.
+            pass
+        elif test_platform.startswith("macosx1015-64"):
+            if "--power-test" in task["mozharness"]["extra-options"]:
+                task["worker-type"] = MACOSX_WORKER_TYPES["macosx1015-64-power"]
+            else:
+                task["worker-type"] = MACOSX_WORKER_TYPES["macosx1015-64"]
+        elif test_platform.startswith("macosx1100-64"):
+            task["worker-type"] = MACOSX_WORKER_TYPES["macosx1100-64"]
+        elif test_platform.startswith("win"):
+            # figure out what platform the job needs to run on
+            if task["virtualization"] == "hardware":
+                # some jobs like talos and reftest run on real h/w - those are all win10
+                if test_platform.startswith("windows10-64-ref-hw-2017"):
+                    win_worker_type_platform = WINDOWS_WORKER_TYPES[
+                        "windows10-64-ref-hw-2017"
+                    ]
+                else:
+                    win_worker_type_platform = WINDOWS_WORKER_TYPES["windows10-64"]
+            else:
+                # the other jobs run on a vm which may or may not be a win10 vm
+                win_worker_type_platform = WINDOWS_WORKER_TYPES[
+                    test_platform.split("/")[0]
+                ]
+                if task[
+                    "virtualization"
+                ] == "virtual-with-gpu" and test_platform.startswith("windows1"):
+                    # add in `--requires-gpu` to the mozharness options
+                    task["mozharness"]["extra-options"].append("--requires-gpu")
+
+            # now we have the right platform set the worker type accordingly
+            task["worker-type"] = win_worker_type_platform[task["virtualization"]]
+        elif test_platform.startswith("android-hw-g5"):
+            if task["suite"] != "raptor":
+                task["worker-type"] = "t-bitbar-gw-unit-g5"
+            else:
+                task["worker-type"] = "t-bitbar-gw-perf-g5"
+        elif test_platform.startswith("android-hw-p5"):
+            if task["suite"] != "raptor":
+                task["worker-type"] = "t-bitbar-gw-unit-p5"
+            else:
+                task["worker-type"] = "t-bitbar-gw-perf-p5"
+        elif test_platform.startswith("android-hw-a51"):
+            if task["suite"] != "raptor":
+                task["worker-type"] = "t-bitbar-gw-unit-a51"
+            else:
+                task["worker-type"] = "t-bitbar-gw-perf-a51"
+        elif test_platform.startswith("android-em-7.0-x86"):
+            task["worker-type"] = "t-linux-kvm"
+        elif test_platform.startswith("linux") or test_platform.startswith("android"):
+            if "wayland" in test_platform:
+                task["worker-type"] = "t-linux-wayland"
+            elif task.get("suite", "") in ["talos", "raptor"] and not task[
+                "build-platform"
+            ].startswith("linux64-ccov"):
+                task["worker-type"] = "t-linux-talos-1804"
+            else:
+                task["worker-type"] = LINUX_WORKER_TYPES[task["instance-size"]]
+        else:
+            raise Exception(f"unknown test_platform {test_platform}")
+
+        yield task
+
+
+@transforms.add
+def set_wayland_env(config, tasks):
+    for task in tasks:
+        if task["worker-type"] != "t-linux-wayland":
+            yield task
+            continue
+
+        env = task.setdefault("worker", {}).setdefault("env", {})
+        env["MOZ_ENABLE_WAYLAND"] = "1"
+        env["WAYLAND_DISPLAY"] = "wayland-0"
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/try_job.py b/taskcluster/gecko_taskgraph/transforms/try_job.py
new file mode 100644
index 0000000000..4b3281f5c5
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/try_job.py
@@ -0,0 +1,18 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def set_job_try_name(config, jobs):
+    """
+    For a task which is governed by `-j` in try syntax, set the `job_try_name`
+    attribute based on the job name.
+    """
+    for job in jobs:
+        job.setdefault("attributes", {}).setdefault("job_try_name", job["name"])
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/update_verify.py b/taskcluster/gecko_taskgraph/transforms/update_verify.py
new file mode 100644
index 0000000000..19c932c746
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/update_verify.py
@@ -0,0 +1,58 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+
+from copy import deepcopy
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import add_suffix, inherit_treeherder_from_dep
+
+from gecko_taskgraph.util.attributes import task_name
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_command(config, tasks):
+    config_tasks = {}
+    for dep in config.kind_dependencies_tasks.values():
+        if (
+            "update-verify-config" in dep.kind
+            or "update-verify-next-config" in dep.kind
+        ):
+            config_tasks[task_name(dep)] = dep
+
+    for task in tasks:
+        config_task = config_tasks[task["name"]]
+        total_chunks = task["extra"]["chunks"]
+        task["worker"].setdefault("env", {})["CHANNEL"] = config_task.task["extra"][
+            "channel"
+        ]
+        task.setdefault("fetches", {})[config_task.label] = [
+            "update-verify.cfg",
+        ]
+        task["treeherder"] = inherit_treeherder_from_dep(task, config_task)
+
+        for this_chunk in range(1, total_chunks + 1):
+            chunked = deepcopy(task)
+            chunked["treeherder"]["symbol"] = add_suffix(
+                chunked["treeherder"]["symbol"], this_chunk
+            )
+            chunked["label"] = "release-update-verify-{}-{}/{}".format(
+                chunked["name"], this_chunk, total_chunks
+            )
+            if not chunked["worker"].get("env"):
+                chunked["worker"]["env"] = {}
+            chunked["run"] = {
+                "using": "run-task",
+                "cwd": "{checkout}",
+                "command": "tools/update-verify/scripts/chunked-verify.sh "
+                f"--total-chunks={total_chunks} --this-chunk={this_chunk}",
+                "sparse-profile": "update-verify",
+            }
+
+            yield chunked
diff --git a/taskcluster/gecko_taskgraph/transforms/update_verify_config.py b/taskcluster/gecko_taskgraph/transforms/update_verify_config.py
new file mode 100644
index 0000000000..1de808f82b
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/update_verify_config.py
@@ -0,0 +1,148 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the beetmover task into an actual task description.
+"""
+
+from urllib.parse import urlsplit
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.transforms.task import get_branch_repo, get_branch_rev
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.scriptworker import get_release_config
+
+transforms = TransformSequence()
+
+
+# The beta regexes do not match point releases.
+# In the rare event that we do ship a point
+# release to beta, we need to either:
+# 1) update these regexes to match that specific version
+# 2) pass a second include version that matches that specific version
+INCLUDE_VERSION_REGEXES = {
+    "beta": r"'^(\d+\.\d+(b\d+)?)$'",
+    "nonbeta": r"'^\d+\.\d+(\.\d+)?$'",
+    # Same as nonbeta, except for the esr suffix
+    "esr": r"'^\d+\.\d+(\.\d+)?esr$'",
+    # Previous esr versions, for update testing before we update users to esr102
+    "esr115-next": r"'^(52|60|68|78|91|102)+\.\d+(\.\d+)?esr$'",
+}
+
+MAR_CHANNEL_ID_OVERRIDE_REGEXES = {
+    "beta": r"'^\d+\.\d+(\.\d+)?$$,firefox-mozilla-beta,firefox-mozilla-release'",
+}
+
+
+def ensure_wrapped_singlequote(regexes):
+    """Ensure that a regex (from INCLUDE_VERSION_REGEXES or MAR_CHANNEL_ID_OVERRIDE_REGEXES)
+    is wrapper in single quotes.
+    """
+    for name, regex in regexes.items():
+        if regex[0] != "'" or regex[-1] != "'":
+            raise Exception(
+                "Regex {} is invalid: not wrapped with single quotes.\n{}".format(
+                    name, regex
+                )
+            )
+
+
+ensure_wrapped_singlequote(INCLUDE_VERSION_REGEXES)
+ensure_wrapped_singlequote(MAR_CHANNEL_ID_OVERRIDE_REGEXES)
+
+
+@transforms.add
+def add_command(config, tasks):
+    keyed_by_args = [
+        "channel",
+        "archive-prefix",
+        "previous-archive-prefix",
+        "aus-server",
+        "override-certs",
+        "include-version",
+        "mar-channel-id-override",
+        "last-watershed",
+    ]
+    optional_args = [
+        "updater-platform",
+    ]
+
+    release_config = get_release_config(config)
+
+    for task in tasks:
+        task["description"] = "generate update verify config for {}".format(
+            task["attributes"]["build_platform"]
+        )
+
+        command = [
+            "python",
+            "testing/mozharness/scripts/release/update-verify-config-creator.py",
+            "--product",
+            task["extra"]["product"],
+            "--stage-product",
+            task["shipping-product"],
+            "--app-name",
+            task["extra"]["app-name"],
+            "--branch-prefix",
+            task["extra"]["branch-prefix"],
+            "--platform",
+            task["extra"]["platform"],
+            "--to-version",
+            release_config["version"],
+            "--to-app-version",
+            release_config["appVersion"],
+            "--to-build-number",
+            str(release_config["build_number"]),
+            "--to-buildid",
+            config.params["moz_build_date"],
+            "--to-revision",
+            get_branch_rev(config),
+            "--output-file",
+            "update-verify.cfg",
+        ]
+
+        repo_path = urlsplit(get_branch_repo(config)).path.lstrip("/")
+        command.extend(["--repo-path", repo_path])
+
+        if release_config.get("partial_versions"):
+            for partial in release_config["partial_versions"].split(","):
+                command.extend(["--partial-version", partial.split("build")[0]])
+
+        for arg in optional_args:
+            if task["extra"].get(arg):
+                command.append(f"--{arg}")
+                command.append(task["extra"][arg])
+
+        for arg in keyed_by_args:
+            thing = f"extra.{arg}"
+            resolve_keyed_by(
+                task,
+                thing,
+                item_name=task["name"],
+                platform=task["attributes"]["build_platform"],
+                **{
+                    "release-type": config.params["release_type"],
+                    "release-level": release_level(config.params["project"]),
+                },
+            )
+            # ignore things that resolved to null
+            if not task["extra"].get(arg):
+                continue
+            if arg == "include-version":
+                task["extra"][arg] = INCLUDE_VERSION_REGEXES[task["extra"][arg]]
+            if arg == "mar-channel-id-override":
+                task["extra"][arg] = MAR_CHANNEL_ID_OVERRIDE_REGEXES[task["extra"][arg]]
+
+            command.append(f"--{arg}")
+            command.append(task["extra"][arg])
+
+        task["run"].update(
+            {
+                "using": "mach",
+                "mach": " ".join(command),
+            }
+        )
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/upload_generated_sources.py b/taskcluster/gecko_taskgraph/transforms/upload_generated_sources.py
new file mode 100644
index 0000000000..b862645eed
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/upload_generated_sources.py
@@ -0,0 +1,40 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the upload-generated-files task description template,
+taskcluster/ci/upload-generated-sources/kind.yml, into an actual task description.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def add_task_info(config, jobs):
+    for job in jobs:
+        dep_task = job["primary-dependency"]
+        del job["primary-dependency"]
+
+        # Add a dependency on the build task.
+        job["dependencies"] = {"build": dep_task.label}
+        # Label the job to match the build task it's uploading from.
+        job["label"] = dep_task.label.replace("build-", "upload-generated-sources-")
+        # Copy over some bits of metdata from the build task.
+        dep_th = dep_task.task["extra"]["treeherder"]
+        job.setdefault("attributes", {})
+        job["attributes"]["build_platform"] = dep_task.attributes.get("build_platform")
+        if dep_task.attributes.get("shippable"):
+            job["attributes"]["shippable"] = True
+        plat = "{}/{}".format(
+            dep_th["machine"]["platform"], dep_task.attributes.get("build_type")
+        )
+        job["treeherder"]["platform"] = plat
+        job["treeherder"]["tier"] = dep_th["tier"]
+        if dep_th["symbol"] != "N":
+            job["treeherder"]["symbol"] = "Ugs{}".format(dep_th["symbol"])
+        job["run-on-projects"] = dep_task.attributes.get("run_on_projects")
+        job["optimization"] = dep_task.optimization
+
+        yield job
diff --git a/taskcluster/gecko_taskgraph/transforms/upload_symbols.py b/taskcluster/gecko_taskgraph/transforms/upload_symbols.py
new file mode 100644
index 0000000000..f6d40e9a45
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/upload_symbols.py
@@ -0,0 +1,95 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Transform the upload-symbols task description template,
+taskcluster/ci/upload-symbols/job-template.yml into an actual task description.
+"""
+
+
+import logging
+
+from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.treeherder import inherit_treeherder_from_dep, join_symbol
+
+from gecko_taskgraph.util.attributes import (
+    RELEASE_PROJECTS,
+    copy_attributes_from_dependent_job,
+)
+
+logger = logging.getLogger(__name__)
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def check_nightlies(config, tasks):
+    """Ensure that we upload symbols for all shippable builds, so that crash-stats can
+    resolve any reports sent to it. Try may enable full symbols but not upload them.
+
+    Putting this check here (instead of the transforms for the build kind) lets us
+    leverage the any not-for-build-platforms set in the update-symbols kind."""
+    for task in tasks:
+        dep = task["primary-dependency"]
+        if (
+            config.params["project"] in RELEASE_PROJECTS
+            and dep.attributes.get("shippable")
+            and not dep.attributes.get("enable-full-crashsymbols")
+            and not dep.attributes.get("skip-upload-crashsymbols")
+        ):
+            raise Exception(
+                "Shippable job %s should have enable-full-crashsymbols attribute "
+                "set to true to enable symbol upload to crash-stats" % dep.label
+            )
+        yield task
+
+
+@transforms.add
+def fill_template(config, tasks):
+    for task in tasks:
+        dep = task["primary-dependency"]
+        task.pop("dependent-tasks", None)
+
+        # Fill out the dynamic fields in the task description
+        task["label"] = dep.label + "-upload-symbols"
+
+        # Skip tasks where we don't have the full crashsymbols enabled
+        if not dep.attributes.get("enable-full-crashsymbols") or dep.attributes.get(
+            "skip-upload-crashsymbols"
+        ):
+            logger.debug("Skipping upload symbols task for %s", task["label"])
+            continue
+
+        task["dependencies"] = {"build": dep.label}
+        task["worker"]["env"]["GECKO_HEAD_REPOSITORY"] = config.params[
+            "head_repository"
+        ]
+        task["worker"]["env"]["GECKO_HEAD_REV"] = config.params["head_rev"]
+        task["worker"]["env"]["SYMBOL_SECRET"] = task["worker"]["env"][
+            "SYMBOL_SECRET"
+        ].format(level=config.params["level"])
+
+        attributes = copy_attributes_from_dependent_job(dep)
+        attributes.update(task.get("attributes", {}))
+        task["attributes"] = attributes
+
+        treeherder = inherit_treeherder_from_dep(task, dep)
+        th = dep.task.get("extra")["treeherder"]
+        th_symbol = th.get("symbol")
+        th_groupsymbol = th.get("groupSymbol", "?")
+
+        # Disambiguate the treeherder symbol.
+        sym = "Sym" + (th_symbol[1:] if th_symbol.startswith("B") else th_symbol)
+        treeherder.setdefault("symbol", join_symbol(th_groupsymbol, sym))
+        task["treeherder"] = treeherder
+
+        # We only want to run these tasks if the build is run.
+        # XXX Better to run this on promote phase instead?
+        task["run-on-projects"] = dep.attributes.get("run_on_projects")
+        task["optimization"] = {"upload-symbols": None}
+        task["if-dependencies"] = ["build"]
+
+        # clear out the stuff that's not part of a task description
+        del task["primary-dependency"]
+
+        yield task
diff --git a/taskcluster/gecko_taskgraph/transforms/upstream_artifact_task.py b/taskcluster/gecko_taskgraph/transforms/upstream_artifact_task.py
new file mode 100644
index 0000000000..62f94a8238
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/transforms/upstream_artifact_task.py
@@ -0,0 +1,29 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Find upstream artifact task.
+"""
+
+from taskgraph.transforms.base import TransformSequence
+
+transforms = TransformSequence()
+
+
+@transforms.add
+def find_upstream_artifact_task(config, jobs):
+    for job in jobs:
+        dep_job = None
+        if job.get("dependent-tasks"):
+            dep_labels = [l for l in job["dependent-tasks"].keys()]
+            for label in dep_labels:
+                if label.endswith("-mac-signing"):
+                    assert (
+                        dep_job is None
+                    ), "Can't determine whether " "{} or {} is dep_job!".format(
+                        dep_job.label, label
+                    )
+                    dep_job = job["dependent-tasks"][label]
+            if dep_job is not None:
+                job["upstream-artifact-task"] = dep_job
+        yield job
diff --git a/taskcluster/gecko_taskgraph/try_option_syntax.py b/taskcluster/gecko_taskgraph/try_option_syntax.py
new file mode 100644
index 0000000000..3e054d63f9
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/try_option_syntax.py
@@ -0,0 +1,755 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import argparse
+import copy
+import logging
+import re
+import shlex
+from collections import defaultdict
+
+logger = logging.getLogger(__name__)
+
+# The build type aliases are very cryptic and only used in try flags these are
+# mappings from the single char alias to a longer more recognizable form.
+BUILD_TYPE_ALIASES = {"o": "opt", "d": "debug"}
+
+# consider anything in this whitelist of kinds to be governed by -b/-p
+BUILD_KINDS = {
+    "build",
+    "artifact-build",
+    "hazard",
+    "l10n",
+    "valgrind",
+    "spidermonkey",
+}
+
+
+# mapping from shortcut name (usable with -u) to a boolean function identifying
+# matching test names
+def alias_prefix(prefix):
+    return lambda name: name.startswith(prefix)
+
+
+def alias_contains(infix):
+    return lambda name: infix in name
+
+
+def alias_matches(pattern):
+    pattern = re.compile(pattern)
+    return lambda name: pattern.match(name)
+
+
+UNITTEST_ALIASES = {
+    # Aliases specify shorthands that can be used in try syntax.  The shorthand
+    # is the dictionary key, with the value representing a pattern for matching
+    # unittest_try_names.
+    #
+    # Note that alias expansion is performed in the absence of any chunk
+    # prefixes.  For example, the first example above would replace "foo-7"
+    # with "foobar-7".  Note that a few aliases allowed chunks to be specified
+    # without a leading `-`, for example 'mochitest-dt1'. That's no longer
+    # supported.
+    "cppunit": alias_prefix("cppunit"),
+    "crashtest": alias_prefix("crashtest"),
+    "crashtest-e10s": alias_prefix("crashtest-e10s"),
+    "e10s": alias_contains("e10s"),
+    "firefox-ui-functional": alias_prefix("firefox-ui-functional"),
+    "gaia-js-integration": alias_contains("gaia-js-integration"),
+    "gtest": alias_prefix("gtest"),
+    "jittest": alias_prefix("jittest"),
+    "jittests": alias_prefix("jittest"),
+    "jsreftest": alias_prefix("jsreftest"),
+    "jsreftest-e10s": alias_prefix("jsreftest-e10s"),
+    "marionette": alias_prefix("marionette"),
+    "mochitest": alias_prefix("mochitest"),
+    "mochitests": alias_prefix("mochitest"),
+    "mochitest-e10s": alias_prefix("mochitest-e10s"),
+    "mochitests-e10s": alias_prefix("mochitest-e10s"),
+    "mochitest-debug": alias_prefix("mochitest-debug-"),
+    "mochitest-a11y": alias_contains("mochitest-a11y"),
+    "mochitest-bc": alias_prefix("mochitest-browser-chrome"),
+    "mochitest-e10s-bc": alias_prefix("mochitest-browser-chrome-e10s"),
+    "mochitest-browser-chrome": alias_prefix("mochitest-browser-chrome"),
+    "mochitest-e10s-browser-chrome": alias_prefix("mochitest-browser-chrome-e10s"),
+    "mochitest-chrome": alias_contains("mochitest-chrome"),
+    "mochitest-dt": alias_prefix("mochitest-devtools-chrome"),
+    "mochitest-e10s-dt": alias_prefix("mochitest-devtools-chrome-e10s"),
+    "mochitest-gl": alias_prefix("mochitest-webgl"),
+    "mochitest-gl-e10s": alias_prefix("mochitest-webgl-e10s"),
+    "mochitest-gpu": alias_prefix("mochitest-gpu"),
+    "mochitest-gpu-e10s": alias_prefix("mochitest-gpu-e10s"),
+    "mochitest-media": alias_prefix("mochitest-media"),
+    "mochitest-media-e10s": alias_prefix("mochitest-media-e10s"),
+    "mochitest-vg": alias_prefix("mochitest-valgrind"),
+    "reftest": alias_matches(r"^(plain-)?reftest.*$"),
+    "reftest-no-accel": alias_matches(r"^(plain-)?reftest-no-accel.*$"),
+    "reftests": alias_matches(r"^(plain-)?reftest.*$"),
+    "reftests-e10s": alias_matches(r"^(plain-)?reftest-e10s.*$"),
+    "robocop": alias_prefix("robocop"),
+    "web-platform-test": alias_prefix("web-platform-tests"),
+    "web-platform-tests": alias_prefix("web-platform-tests"),
+    "web-platform-tests-e10s": alias_prefix("web-platform-tests-e10s"),
+    "web-platform-tests-crashtests": alias_prefix("web-platform-tests-crashtest"),
+    "web-platform-tests-print-reftest": alias_prefix(
+        "web-platform-tests-print-reftest"
+    ),
+    "web-platform-tests-reftests": alias_prefix("web-platform-tests-reftest"),
+    "web-platform-tests-reftests-e10s": alias_prefix("web-platform-tests-reftest-e10s"),
+    "web-platform-tests-wdspec": alias_prefix("web-platform-tests-wdspec"),
+    "web-platform-tests-wdspec-e10s": alias_prefix("web-platform-tests-wdspec-e10s"),
+    "xpcshell": alias_prefix("xpcshell"),
+}
+
+# unittest platforms can be specified by substring of the "pretty name", which
+# is basically the old Buildbot builder name.  This dict has {pretty name,
+# [test_platforms]} translations, This includes only the most commonly-used
+# substrings.  It is OK to add new test platforms to various shorthands here;
+# if you add a new Linux64 test platform for instance, people will expect that
+# their previous methods of requesting "all linux64 tests" will include this
+# new platform, and they shouldn't have to explicitly spell out the new platform
+# every time for such cases.
+#
+# Note that the test platforms here are only the prefix up to the `/`.
+UNITTEST_PLATFORM_PRETTY_NAMES = {
+    "Ubuntu": [
+        "linux32",
+        "linux64",
+        "linux64-asan",
+        "linux1804-64",
+        "linux1804-64-asan",
+    ],
+    "x64": ["linux64", "linux64-asan", "linux1804-64", "linux1804-64-asan"],
+    "Android 7.0 Moto G5 32bit": ["android-hw-g5-7.0-arm7"],
+    "Android 7.0 Samsung A51 32bit": ["android-hw-a51-11.0-arm7"],
+    "Android 7.0 Samsung A51 64bit": ["android-hw-a51-11.0-aarch64"],
+    "Android 8.0 Google Pixel 2 32bit": ["android-hw-p2-8.0-arm7"],
+    "Android 8.0 Google Pixel 2 64bit": ["android-hw-p2-8.0-android-aarch64"],
+    "Android 13.0 Google Pixel 5 32bit": ["android-hw-p5-13.0-arm7"],
+    "Android 13.0 Google Pixel 5 64bit": ["android-hw-p5-13.0-android-aarch64"],
+    "Windows 7": ["windows7-32"],
+    "Windows 7 VM": ["windows7-32-vm"],
+    "Windows 10": ["windows10-64"],
+}
+
+TEST_CHUNK_SUFFIX = re.compile("(.*)-([0-9]+)$")
+
+
+def escape_whitespace_in_brackets(input_str):
+    """
+    In tests you may restrict them by platform [] inside of the brackets
+    whitespace may occur this is typically invalid shell syntax so we escape it
+    with backslash sequences    .
+    """
+    result = ""
+    in_brackets = False
+    for char in input_str:
+        if char == "[":
+            in_brackets = True
+            result += char
+            continue
+
+        if char == "]":
+            in_brackets = False
+            result += char
+            continue
+
+        if char == " " and in_brackets:
+            result += r"\ "
+            continue
+
+        result += char
+
+    return result
+
+
+def split_try_msg(message):
+    try:
+        try_idx = message.index("try:")
+    except ValueError:
+        return []
+    message = message[try_idx:].split("\n")[0]
+    # shlex used to ensure we split correctly when giving values to argparse.
+    return shlex.split(escape_whitespace_in_brackets(message))
+
+
+def parse_message(message):
+    parts = split_try_msg(message)
+
+    # Argument parser based on try flag flags
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-b", "--build", dest="build_types")
+    parser.add_argument(
+        "-p", "--platform", nargs="?", dest="platforms", const="all", default="all"
+    )
+    parser.add_argument(
+        "-u", "--unittests", nargs="?", dest="unittests", const="all", default="all"
+    )
+    parser.add_argument(
+        "-t", "--talos", nargs="?", dest="talos", const="all", default="none"
+    )
+    parser.add_argument(
+        "-r", "--raptor", nargs="?", dest="raptor", const="all", default="none"
+    )
+    parser.add_argument(
+        "-i", "--interactive", dest="interactive", action="store_true", default=False
+    )
+    parser.add_argument(
+        "-e", "--all-emails", dest="notifications", action="store_const", const="all"
+    )
+    parser.add_argument(
+        "-f",
+        "--failure-emails",
+        dest="notifications",
+        action="store_const",
+        const="failure",
+    )
+    parser.add_argument("-j", "--job", dest="jobs", action="append")
+    parser.add_argument(
+        "--rebuild-talos",
+        dest="talos_trigger_tests",
+        action="store",
+        type=int,
+        default=1,
+    )
+    parser.add_argument(
+        "--rebuild-raptor",
+        dest="raptor_trigger_tests",
+        action="store",
+        type=int,
+        default=1,
+    )
+    parser.add_argument("--setenv", dest="env", action="append")
+    parser.add_argument("--gecko-profile", dest="profile", action="store_true")
+    parser.add_argument("--tag", dest="tag", action="store", default=None)
+    parser.add_argument("--no-retry", dest="no_retry", action="store_true")
+    parser.add_argument(
+        "--include-nightly", dest="include_nightly", action="store_true"
+    )
+    parser.add_argument("--artifact", dest="artifact", action="store_true")
+
+    # While we are transitioning from BB to TC, we want to push jobs to tc-worker
+    # machines but not overload machines with every try push. Therefore, we add
+    # this temporary option to be able to push jobs to tc-worker.
+    parser.add_argument(
+        "-w",
+        "--taskcluster-worker",
+        dest="taskcluster_worker",
+        action="store_true",
+        default=False,
+    )
+
+    # In order to run test jobs multiple times
+    parser.add_argument("--rebuild", dest="trigger_tests", type=int, default=1)
+    args, _ = parser.parse_known_args(parts)
+
+    try_options = vars(args)
+    try_task_config = {
+        "use-artifact-builds": try_options.pop("artifact"),
+        "gecko-profile": try_options.pop("profile"),
+        "env": dict(arg.split("=") for arg in try_options.pop("env") or []),
+    }
+    return {
+        "try_options": try_options,
+        "try_task_config": try_task_config,
+    }
+
+
+class TryOptionSyntax:
+    def __init__(self, parameters, full_task_graph, graph_config):
+        """
+        Apply the try options in parameters.
+
+        The resulting object has attributes:
+
+        - build_types: a list containing zero or more of 'opt' and 'debug'
+        - platforms: a list of selected platform names, or None for all
+        - unittests: a list of tests, of the form given below, or None for all
+        - jobs: a list of requested job names, or None for all
+        - trigger_tests: the number of times tests should be triggered (--rebuild)
+        - interactive: true if --interactive
+        - notifications: either None if no notifications or one of 'all' or 'failure'
+        - talos_trigger_tests: the number of time talos tests should be triggered (--rebuild-talos)
+        - tag: restrict tests to the specified tag
+        - no_retry: do not retry failed jobs
+
+        The unittests and talos lists contain dictionaries of the form:
+
+        {
+            'test': '<suite name>',
+            'platforms': [..platform names..], # to limit to only certain platforms
+            'only_chunks': set([..chunk numbers..]), # to limit only to certain chunks
+        }
+        """
+        self.full_task_graph = full_task_graph
+        self.graph_config = graph_config
+        self.jobs = []
+        self.build_types = []
+        self.platforms = []
+        self.unittests = []
+        self.talos = []
+        self.raptor = []
+        self.trigger_tests = 0
+        self.interactive = False
+        self.notifications = None
+        self.talos_trigger_tests = 0
+        self.raptor_trigger_tests = 0
+        self.tag = None
+        self.no_retry = False
+
+        options = parameters["try_options"]
+        if not options:
+            return None
+        self.jobs = self.parse_jobs(options["jobs"])
+        self.build_types = self.parse_build_types(
+            options["build_types"], full_task_graph
+        )
+        self.platforms = self.parse_platforms(options, full_task_graph)
+        self.unittests = self.parse_test_option(
+            "unittest_try_name", options["unittests"], full_task_graph
+        )
+        self.talos = self.parse_test_option(
+            "talos_try_name", options["talos"], full_task_graph
+        )
+        self.raptor = self.parse_test_option(
+            "raptor_try_name", options["raptor"], full_task_graph
+        )
+        self.trigger_tests = options["trigger_tests"]
+        self.interactive = options["interactive"]
+        self.notifications = options["notifications"]
+        self.talos_trigger_tests = options["talos_trigger_tests"]
+        self.raptor_trigger_tests = options["raptor_trigger_tests"]
+        self.tag = options["tag"]
+        self.no_retry = options["no_retry"]
+        self.include_nightly = options["include_nightly"]
+
+        self.test_tiers = self.generate_test_tiers(full_task_graph)
+
+    def generate_test_tiers(self, full_task_graph):
+        retval = defaultdict(set)
+        for t in full_task_graph.tasks.values():
+            if t.attributes.get("kind") == "test":
+                try:
+                    tier = t.task["extra"]["treeherder"]["tier"]
+                    name = t.attributes.get("unittest_try_name")
+                    retval[name].add(tier)
+                except KeyError:
+                    pass
+
+        return retval
+
+    def parse_jobs(self, jobs_arg):
+        if not jobs_arg or jobs_arg == ["none"]:
+            return []  # default is `-j none`
+        if jobs_arg == ["all"]:
+            return None
+        expanded = []
+        for job in jobs_arg:
+            expanded.extend(j.strip() for j in job.split(","))
+        return expanded
+
+    def parse_build_types(self, build_types_arg, full_task_graph):
+        if build_types_arg is None:
+            build_types_arg = []
+
+        build_types = [
+            _f
+            for _f in (
+                BUILD_TYPE_ALIASES.get(build_type) for build_type in build_types_arg
+            )
+            if _f
+        ]
+
+        all_types = {
+            t.attributes["build_type"]
+            for t in full_task_graph.tasks.values()
+            if "build_type" in t.attributes
+        }
+        bad_types = set(build_types) - all_types
+        if bad_types:
+            raise Exception(
+                "Unknown build type(s) [%s] specified for try" % ",".join(bad_types)
+            )
+
+        return build_types
+
+    def parse_platforms(self, options, full_task_graph):
+        platform_arg = options["platforms"]
+        if platform_arg == "all":
+            return None
+
+        RIDEALONG_BUILDS = self.graph_config["try"]["ridealong-builds"]
+        results = []
+        for build in platform_arg.split(","):
+            if build in ("macosx64",):
+                # Regular opt builds are faster than shippable ones, but we don't run
+                # tests against them.
+                # We want to choose them (and only them) if no tests were requested.
+                if (
+                    options["unittests"] == "none"
+                    and options["talos"] == "none"
+                    and options["raptor"] == "none"
+                ):
+                    results.append("macosx64")
+                    logger.info("adding macosx64 for try syntax using macosx64.")
+                # Otherwise, use _just_ the shippable builds.
+                else:
+                    results.append("macosx64-shippable")
+                    logger.info(
+                        "adding macosx64-shippable for try syntax using macosx64."
+                    )
+            else:
+                results.append(build)
+            if build in RIDEALONG_BUILDS:
+                results.extend(RIDEALONG_BUILDS[build])
+                logger.info(
+                    "platform %s triggers ridealong builds %s"
+                    % (build, ", ".join(RIDEALONG_BUILDS[build]))
+                )
+
+        test_platforms = {
+            t.attributes["test_platform"]
+            for t in full_task_graph.tasks.values()
+            if "test_platform" in t.attributes
+        }
+        build_platforms = {
+            t.attributes["build_platform"]
+            for t in full_task_graph.tasks.values()
+            if "build_platform" in t.attributes
+        }
+        all_platforms = test_platforms | build_platforms
+        bad_platforms = set(results) - all_platforms
+        if bad_platforms:
+            raise Exception(
+                "Unknown platform(s) [%s] specified for try" % ",".join(bad_platforms)
+            )
+
+        return results
+
+    def parse_test_option(self, attr_name, test_arg, full_task_graph):
+        """
+
+        Parse a unittest (-u) or talos (-t) option, in the context of a full
+        task graph containing available `unittest_try_name` or `talos_try_name`
+        attributes.  There are three cases:
+
+            - test_arg is == 'none' (meaning an empty list)
+            - test_arg is == 'all' (meaning use the list of jobs for that job type)
+            - test_arg is comma string which needs to be parsed
+        """
+
+        # Empty job list case...
+        if test_arg is None or test_arg == "none":
+            return []
+
+        all_platforms = {
+            t.attributes["test_platform"].split("/")[0]
+            for t in full_task_graph.tasks.values()
+            if "test_platform" in t.attributes
+        }
+
+        tests = self.parse_test_opts(test_arg, all_platforms)
+
+        if not tests:
+            return []
+
+        all_tests = {
+            t.attributes[attr_name]
+            for t in full_task_graph.tasks.values()
+            if attr_name in t.attributes
+        }
+
+        # Special case where tests is 'all' and must be expanded
+        if tests[0]["test"] == "all":
+            results = []
+            all_entry = tests[0]
+            for test in all_tests:
+                entry = {"test": test}
+                # If there are platform restrictions copy them across the list.
+                if "platforms" in all_entry:
+                    entry["platforms"] = list(all_entry["platforms"])
+                results.append(entry)
+            return self.parse_test_chunks(all_tests, results)
+        return self.parse_test_chunks(all_tests, tests)
+
+    def parse_test_opts(self, input_str, all_platforms):
+        """
+        Parse `testspec,testspec,..`, where each testspec is a test name
+        optionally followed by a list of test platforms or negated platforms in
+        `[]`.
+
+        No brackets indicates that tests should run on all platforms for which
+        builds are available.  If testspecs are provided, then each is treated,
+        from left to right, as an instruction to include or (if negated)
+        exclude a set of test platforms.  A single spec may expand to multiple
+        test platforms via UNITTEST_PLATFORM_PRETTY_NAMES.  If the first test
+        spec is negated, processing begins with the full set of available test
+        platforms; otherwise, processing begins with an empty set of test
+        platforms.
+        """
+
+        # Final results which we will return.
+        tests = []
+
+        cur_test = {}
+        token = ""
+        in_platforms = False
+
+        def normalize_platforms():
+            if "platforms" not in cur_test:
+                return
+            # if the first spec is a negation, start with all platforms
+            if cur_test["platforms"][0][0] == "-":
+                platforms = all_platforms.copy()
+            else:
+                platforms = []
+            for platform in cur_test["platforms"]:
+                if platform[0] == "-":
+                    platforms = [p for p in platforms if p != platform[1:]]
+                else:
+                    platforms.append(platform)
+            cur_test["platforms"] = platforms
+
+        def add_test(value):
+            normalize_platforms()
+            cur_test["test"] = value.strip()
+            tests.insert(0, cur_test)
+
+        def add_platform(value):
+            platform = value.strip()
+            if platform[0] == "-":
+                negated = True
+                platform = platform[1:]
+            else:
+                negated = False
+            platforms = UNITTEST_PLATFORM_PRETTY_NAMES.get(platform, [platform])
+            if negated:
+                platforms = ["-" + p for p in platforms]
+            cur_test["platforms"] = platforms + cur_test.get("platforms", [])
+
+        # This might be somewhat confusing but we parse the string _backwards_ so
+        # there is no ambiguity over what state we are in.
+        for char in reversed(input_str):
+
+            # , indicates exiting a state
+            if char == ",":
+
+                # Exit a particular platform.
+                if in_platforms:
+                    add_platform(token)
+
+                # Exit a particular test.
+                else:
+                    add_test(token)
+                    cur_test = {}
+
+                # Token must always be reset after we exit a state
+                token = ""
+            elif char == "[":
+                # Exiting platform state entering test state.
+                add_platform(token)
+                token = ""
+                in_platforms = False
+            elif char == "]":
+                # Entering platform state.
+                in_platforms = True
+            else:
+                # Accumulator.
+                token = char + token
+
+        # Handle any left over tokens.
+        if token:
+            add_test(token)
+
+        return tests
+
+    def handle_alias(self, test, all_tests):
+        """
+        Expand a test if its name refers to an alias, returning a list of test
+        dictionaries cloned from the first (to maintain any metadata).
+        """
+        if test["test"] not in UNITTEST_ALIASES:
+            return [test]
+
+        alias = UNITTEST_ALIASES[test["test"]]
+
+        def mktest(name):
+            newtest = copy.deepcopy(test)
+            newtest["test"] = name
+            return newtest
+
+        def exprmatch(alias):
+            return [t for t in all_tests if alias(t)]
+
+        return [mktest(t) for t in exprmatch(alias)]
+
+    def parse_test_chunks(self, all_tests, tests):
+        """
+        Test flags may include parameters to narrow down the number of chunks in a
+        given push. We don't model 1 chunk = 1 job in taskcluster so we must check
+        each test flag to see if it is actually specifying a chunk.
+        """
+        results = []
+        seen_chunks = {}
+        for test in tests:
+            matches = TEST_CHUNK_SUFFIX.match(test["test"])
+            if matches:
+                name = matches.group(1)
+                chunk = matches.group(2)
+                if name in seen_chunks:
+                    seen_chunks[name].add(chunk)
+                else:
+                    seen_chunks[name] = {chunk}
+                    test["test"] = name
+                    test["only_chunks"] = seen_chunks[name]
+                    results.append(test)
+            else:
+                results.extend(self.handle_alias(test, all_tests))
+
+        # uniquify the results over the test names
+        results = sorted(
+            {test["test"]: test for test in results}.values(),
+            key=lambda test: test["test"],
+        )
+        return results
+
+    def find_all_attribute_suffixes(self, graph, prefix):
+        rv = set()
+        for t in graph.tasks.values():
+            for a in t.attributes:
+                if a.startswith(prefix):
+                    rv.add(a[len(prefix) :])
+        return sorted(rv)
+
+    def task_matches(self, task):
+        attr = task.attributes.get
+
+        def check_run_on_projects():
+            return {"all"} & set(attr("run_on_projects", []))
+
+        def match_test(try_spec, attr_name):
+            run_by_default = True
+            if attr("build_type") not in self.build_types:
+                return False
+
+            if (
+                self.platforms is not None
+                and attr("build_platform") not in self.platforms
+            ):
+                return False
+            if not check_run_on_projects():
+                run_by_default = False
+
+            if try_spec is None:
+                return run_by_default
+
+            # TODO: optimize this search a bit
+            for test in try_spec:
+                if attr(attr_name) == test["test"]:
+                    break
+            else:
+                return False
+
+            if "only_chunks" in test and attr("test_chunk") not in test["only_chunks"]:
+                return False
+
+            tier = task.task["extra"]["treeherder"]["tier"]
+            if "platforms" in test:
+                if "all" in test["platforms"]:
+                    return True
+                platform = attr("test_platform", "").split("/")[0]
+                # Platforms can be forced by syntax like "-u xpcshell[Windows 8]"
+                return platform in test["platforms"]
+            if tier != 1:
+                # Run Tier 2/3 tests if their build task is Tier 2/3 OR if there is
+                # no tier 1 test of that name.
+                build_task = self.full_task_graph.tasks[task.dependencies["build"]]
+                build_task_tier = build_task.task["extra"]["treeherder"]["tier"]
+
+                name = attr("unittest_try_name")
+                test_tiers = self.test_tiers.get(name)
+
+                if tier <= build_task_tier:
+                    logger.debug(
+                        "not skipping tier {} test {} because build task {} "
+                        "is tier {}".format(
+                            tier, task.label, build_task.label, build_task_tier
+                        )
+                    )
+                    return True
+                if 1 not in test_tiers:
+                    logger.debug(
+                        "not skipping tier {} test {} without explicit inclusion; "
+                        "it is configured to run on tiers {}".format(
+                            tier, task.label, test_tiers
+                        )
+                    )
+                    return True
+                logger.debug(
+                    "skipping tier {} test {} because build task {} is "
+                    "tier {} and there is a higher-tier test of the same name".format(
+                        tier, task.label, build_task.label, build_task_tier
+                    )
+                )
+                return False
+            if run_by_default:
+                return check_run_on_projects()
+            return False
+
+        if attr("job_try_name"):
+            # Beware the subtle distinction between [] and None for self.jobs and self.platforms.
+            # They will be [] if there was no try syntax, and None if try syntax was detected but
+            # they remained unspecified.
+            if self.jobs is not None:
+                return attr("job_try_name") in self.jobs
+
+            # User specified `-j all`
+            if (
+                self.platforms is not None
+                and attr("build_platform") not in self.platforms
+            ):
+                return False  # honor -p for jobs governed by a platform
+            # "all" means "everything with `try` in run_on_projects"
+            return check_run_on_projects()
+        if attr("kind") == "test":
+            return (
+                match_test(self.unittests, "unittest_try_name")
+                or match_test(self.talos, "talos_try_name")
+                or match_test(self.raptor, "raptor_try_name")
+            )
+        if attr("kind") in BUILD_KINDS:
+            if attr("build_type") not in self.build_types:
+                return False
+            if self.platforms is None:
+                # for "-p all", look for try in the 'run_on_projects' attribute
+                return check_run_on_projects()
+            if attr("build_platform") not in self.platforms:
+                return False
+            return True
+        return False
+
+    def __str__(self):
+        def none_for_all(list):
+            if list is None:
+                return "<all>"
+            return ", ".join(str(e) for e in list)
+
+        return "\n".join(
+            [
+                "build_types: " + ", ".join(self.build_types),
+                "platforms: " + none_for_all(self.platforms),
+                "unittests: " + none_for_all(self.unittests),
+                "talos: " + none_for_all(self.talos),
+                "raptor" + none_for_all(self.raptor),
+                "jobs: " + none_for_all(self.jobs),
+                "trigger_tests: " + str(self.trigger_tests),
+                "interactive: " + str(self.interactive),
+                "notifications: " + str(self.notifications),
+                "talos_trigger_tests: " + str(self.talos_trigger_tests),
+                "raptor_trigger_tests: " + str(self.raptor_trigger_tests),
+                "tag: " + str(self.tag),
+                "no_retry: " + str(self.no_retry),
+            ]
+        )
diff --git a/taskcluster/gecko_taskgraph/util/__init__.py b/taskcluster/gecko_taskgraph/util/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/__init__.py
diff --git a/taskcluster/gecko_taskgraph/util/attributes.py b/taskcluster/gecko_taskgraph/util/attributes.py
new file mode 100644
index 0000000000..0ed0be5a8d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/attributes.py
@@ -0,0 +1,143 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import re
+
+INTEGRATION_PROJECTS = {
+    "autoland",
+}
+
+TRUNK_PROJECTS = INTEGRATION_PROJECTS | {"mozilla-central", "comm-central"}
+
+RELEASE_PROJECTS = {
+    "mozilla-central",
+    "mozilla-beta",
+    "mozilla-release",
+    "mozilla-esr102",
+    "mozilla-esr115",
+    "comm-central",
+    "comm-beta",
+    "comm-esr102",
+    "comm-esr115",
+}
+
+RELEASE_PROMOTION_PROJECTS = {
+    "jamun",
+    "maple",
+    "try",
+    "try-comm-central",
+} | RELEASE_PROJECTS
+
+TEMPORARY_PROJECTS = set(
+    {
+        # When using a "Disposable Project Branch" you can specify your branch here. e.g.:
+        "oak",
+    }
+)
+
+TRY_PROJECTS = {
+    "try",
+    "try-comm-central",
+}
+
+ALL_PROJECTS = RELEASE_PROMOTION_PROJECTS | TRUNK_PROJECTS | TEMPORARY_PROJECTS
+
+RUN_ON_PROJECT_ALIASES = {
+    # key is alias, value is lambda to test it against
+    "all": lambda project: True,
+    "integration": lambda project: (
+        project in INTEGRATION_PROJECTS or project == "toolchains"
+    ),
+    "release": lambda project: (project in RELEASE_PROJECTS or project == "toolchains"),
+    "trunk": lambda project: (project in TRUNK_PROJECTS or project == "toolchains"),
+    "trunk-only": lambda project: project in TRUNK_PROJECTS,
+    "autoland": lambda project: project in ("autoland", "toolchains"),
+    "autoland-only": lambda project: project == "autoland",
+    "mozilla-central": lambda project: project in ("mozilla-central", "toolchains"),
+    "mozilla-central-only": lambda project: project == "mozilla-central",
+}
+
+_COPYABLE_ATTRIBUTES = (
+    "accepted-mar-channel-ids",
+    "artifact_map",
+    "artifact_prefix",
+    "build_platform",
+    "build_type",
+    "l10n_chunk",
+    "locale",
+    "mar-channel-id",
+    "maven_packages",
+    "nightly",
+    "required_signoffs",
+    "shippable",
+    "shipping_phase",
+    "shipping_product",
+    "signed",
+    "stub-installer",
+    "update-channel",
+)
+
+
+def match_run_on_projects(project, run_on_projects):
+    """Determine whether the given project is included in the `run-on-projects`
+    parameter, applying expansions for things like "integration" mentioned in
+    the attribute documentation."""
+    aliases = RUN_ON_PROJECT_ALIASES.keys()
+    run_aliases = set(aliases) & set(run_on_projects)
+    if run_aliases:
+        if any(RUN_ON_PROJECT_ALIASES[alias](project) for alias in run_aliases):
+            return True
+
+    return project in run_on_projects
+
+
+def match_run_on_hg_branches(hg_branch, run_on_hg_branches):
+    """Determine whether the given project is included in the `run-on-hg-branches`
+    parameter. Allows 'all'."""
+    if "all" in run_on_hg_branches:
+        return True
+
+    for expected_hg_branch_pattern in run_on_hg_branches:
+        if re.match(expected_hg_branch_pattern, hg_branch):
+            return True
+
+    return False
+
+
+def copy_attributes_from_dependent_job(dep_job, denylist=()):
+    return {
+        attr: dep_job.attributes[attr]
+        for attr in _COPYABLE_ATTRIBUTES
+        if attr in dep_job.attributes and attr not in denylist
+    }
+
+
+def sorted_unique_list(*args):
+    """Join one or more lists, and return a sorted list of unique members"""
+    combined = set().union(*args)
+    return sorted(combined)
+
+
+def release_level(project):
+    """
+    Whether this is a staging release or not.
+
+    :return str: One of "production" or "staging".
+    """
+    return "production" if project in RELEASE_PROJECTS else "staging"
+
+
+def is_try(params):
+    """
+    Determine whether this graph is being built on a try project or for
+    `mach try fuzzy`.
+    """
+    return "try" in params["project"] or params["try_mode"] == "try_select"
+
+
+def task_name(task):
+    if task.label.startswith(task.kind + "-"):
+        return task.label[len(task.kind) + 1 :]
+    raise AttributeError(f"Task {task.label} does not have a name.")
diff --git a/taskcluster/gecko_taskgraph/util/backstop.py b/taskcluster/gecko_taskgraph/util/backstop.py
new file mode 100644
index 0000000000..26c9a4fb91
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/backstop.py
@@ -0,0 +1,84 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from requests import HTTPError
+from taskgraph.util.taskcluster import find_task_id, get_artifact
+
+from gecko_taskgraph.util.attributes import INTEGRATION_PROJECTS, TRY_PROJECTS
+from gecko_taskgraph.util.taskcluster import state_task
+
+BACKSTOP_PUSH_INTERVAL = 20
+BACKSTOP_TIME_INTERVAL = 60 * 4  # minutes
+BACKSTOP_INDEX = "{trust-domain}.v2.{project}.latest.taskgraph.backstop"
+
+
+def is_backstop(
+    params,
+    push_interval=BACKSTOP_PUSH_INTERVAL,
+    time_interval=BACKSTOP_TIME_INTERVAL,
+    trust_domain="gecko",
+    integration_projects=INTEGRATION_PROJECTS,
+):
+    """Determines whether the given parameters represent a backstop push.
+
+    Args:
+        push_interval (int): Number of pushes
+        time_interval (int): Minutes between forced schedules.
+                             Use 0 to disable.
+        trust_domain (str): "gecko" for Firefox, "comm" for Thunderbird
+        integration_projects (set): project that uses backstop optimization
+    Returns:
+        bool: True if this is a backstop, otherwise False.
+    """
+    # In case this is being faked on try.
+    if params.get("backstop", False):
+        return True
+
+    project = params["project"]
+    pushid = int(params["pushlog_id"])
+    pushdate = int(params["pushdate"])
+
+    if project in TRY_PROJECTS:
+        return False
+    if project not in integration_projects:
+        return True
+
+    # On every Nth push, want to run all tasks.
+    if pushid % push_interval == 0:
+        return True
+
+    if time_interval <= 0:
+        return False
+
+    # We also want to ensure we run all tasks at least once per N minutes.
+    subs = {"trust-domain": trust_domain, "project": project}
+    index = BACKSTOP_INDEX.format(**subs)
+
+    try:
+        last_backstop_id = find_task_id(index)
+    except KeyError:
+        # Index wasn't found, implying there hasn't been a backstop push yet.
+        return True
+
+    if state_task(last_backstop_id) in ("failed", "exception"):
+        # If the last backstop failed its decision task, make this a backstop.
+        return True
+
+    try:
+        last_pushdate = get_artifact(last_backstop_id, "public/parameters.yml")[
+            "pushdate"
+        ]
+    except HTTPError as e:
+        # If the last backstop decision task exists in the index, but
+        # parameters.yml isn't available yet, it means the decision task is
+        # still running. If that's the case, we can be pretty sure the time
+        # component will not cause a backstop, so just return False.
+        if e.response.status_code == 404:
+            return False
+        raise
+
+    if (pushdate - last_pushdate) / 60 >= time_interval:
+        return True
+    return False
diff --git a/taskcluster/gecko_taskgraph/util/bugbug.py b/taskcluster/gecko_taskgraph/util/bugbug.py
new file mode 100644
index 0000000000..50e02d69c6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/bugbug.py
@@ -0,0 +1,125 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import os
+import sys
+import time
+
+import requests
+from mozbuild.util import memoize
+from taskgraph import create
+from taskgraph.util.taskcluster import requests_retry_session
+
+try:
+    # TODO(py3): use time.monotonic()
+    from time import monotonic
+except ImportError:
+    from time import time as monotonic
+
+BUGBUG_BASE_URL = "https://bugbug.herokuapp.com"
+RETRY_TIMEOUT = 9 * 60  # seconds
+RETRY_INTERVAL = 10  # seconds
+
+# Preset confidence thresholds.
+CT_LOW = 0.7
+CT_MEDIUM = 0.8
+CT_HIGH = 0.9
+
+GROUP_TRANSLATIONS = {
+    "testing/web-platform/tests": "",
+    "testing/web-platform/mozilla/tests": "/_mozilla",
+}
+
+
+def translate_group(group):
+    for prefix, value in GROUP_TRANSLATIONS.items():
+        if group.startswith(prefix):
+            return group.replace(prefix, value)
+
+    return group
+
+
+class BugbugTimeoutException(Exception):
+    pass
+
+
+@memoize
+def get_session():
+    s = requests.Session()
+    s.headers.update({"X-API-KEY": "gecko-taskgraph"})
+    return requests_retry_session(retries=5, session=s)
+
+
+def _write_perfherder_data(lower_is_better):
+    if os.environ.get("MOZ_AUTOMATION", "0") == "1":
+        perfherder_data = {
+            "framework": {"name": "build_metrics"},
+            "suites": [
+                {
+                    "name": suite,
+                    "value": value,
+                    "lowerIsBetter": True,
+                    "shouldAlert": False,
+                    "subtests": [],
+                }
+                for suite, value in lower_is_better.items()
+            ],
+        }
+        print(f"PERFHERDER_DATA: {json.dumps(perfherder_data)}", file=sys.stderr)
+
+
+@memoize
+def push_schedules(branch, rev):
+    # Noop if we're in test-action-callback
+    if create.testing:
+        return
+
+    url = BUGBUG_BASE_URL + "/push/{branch}/{rev}/schedules".format(
+        branch=branch, rev=rev
+    )
+    start = monotonic()
+    session = get_session()
+
+    # On try there is no fallback and pulling is slower, so we allow bugbug more
+    # time to compute the results.
+    # See https://github.com/mozilla/bugbug/issues/1673.
+    timeout = RETRY_TIMEOUT
+    if branch == "try":
+        timeout += int(timeout / 3)
+
+    attempts = timeout / RETRY_INTERVAL
+    i = 0
+    while i < attempts:
+        r = session.get(url)
+        r.raise_for_status()
+
+        if r.status_code != 202:
+            break
+
+        time.sleep(RETRY_INTERVAL)
+        i += 1
+    end = monotonic()
+
+    _write_perfherder_data(
+        lower_is_better={
+            "bugbug_push_schedules_time": end - start,
+            "bugbug_push_schedules_retries": i,
+        }
+    )
+
+    data = r.json()
+    if r.status_code == 202:
+        raise BugbugTimeoutException(f"Timed out waiting for result from '{url}'")
+
+    if "groups" in data:
+        data["groups"] = {translate_group(k): v for k, v in data["groups"].items()}
+
+    if "config_groups" in data:
+        data["config_groups"] = {
+            translate_group(k): v for k, v in data["config_groups"].items()
+        }
+
+    return data
diff --git a/taskcluster/gecko_taskgraph/util/cached_tasks.py b/taskcluster/gecko_taskgraph/util/cached_tasks.py
new file mode 100644
index 0000000000..fff9bb9844
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/cached_tasks.py
@@ -0,0 +1,82 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import hashlib
+import time
+
+TARGET_CACHE_INDEX = "{trust_domain}.cache.level-{level}.{type}.{name}.hash.{digest}"
+EXTRA_CACHE_INDEXES = [
+    "{trust_domain}.cache.level-{level}.{type}.{name}.latest",
+    "{trust_domain}.cache.level-{level}.{type}.{name}.pushdate.{build_date_long}",
+]
+
+
+def add_optimization(
+    config, taskdesc, cache_type, cache_name, digest=None, digest_data=None
+):
+    """
+    Allow the results of this task to be cached. This adds index routes to the
+    task so it can be looked up for future runs, and optimization hints so that
+    cached artifacts can be found. Exactly one of `digest` and `digest_data`
+    must be passed.
+
+    :param TransformConfig config: The configuration for the kind being transformed.
+    :param dict taskdesc: The description of the current task.
+    :param str cache_type: The type of task result being cached.
+    :param str cache_name: The name of the object being cached.
+    :param digest: A unique string indentifying this version of the artifacts
+        being generated. Typically this will be the hash of inputs to the task.
+    :type digest: bytes or None
+    :param digest_data: A list of bytes representing the inputs of this task.
+        They will be concatenated and hashed to create the digest for this
+        task.
+    :type digest_data: list of bytes or None
+    """
+    cached_task = taskdesc.get("attributes", {}).get("cached_task")
+    if cached_task is False:
+        return
+
+    if (digest is None) == (digest_data is None):
+        raise Exception("Must pass exactly one of `digest` and `digest_data`.")
+    if digest is None:
+        digest = hashlib.sha256("\n".join(digest_data).encode("utf-8")).hexdigest()
+
+    subs = {
+        "trust_domain": config.graph_config["trust-domain"],
+        "type": cache_type,
+        "name": cache_name,
+        "digest": digest,
+    }
+
+    # We'll try to find a cached version of the toolchain at levels above
+    # and including the current level, starting at the highest level.
+    index_routes = []
+    for level in reversed(range(int(config.params["level"]), 4)):
+        subs["level"] = level
+        index_routes.append(TARGET_CACHE_INDEX.format(**subs))
+    taskdesc["optimization"] = {"index-search": index_routes}
+
+    # ... and cache at the lowest level.
+    taskdesc.setdefault("routes", []).append(
+        f"index.{TARGET_CACHE_INDEX.format(**subs)}"
+    )
+
+    # ... and add some extra routes for humans
+    subs["build_date_long"] = time.strftime(
+        "%Y.%m.%d.%Y%m%d%H%M%S", time.gmtime(config.params["build_date"])
+    )
+    taskdesc["routes"].extend(
+        [f"index.{route.format(**subs)}" for route in EXTRA_CACHE_INDEXES]
+    )
+
+    taskdesc["attributes"]["cached_task"] = {
+        "type": cache_type,
+        "name": cache_name,
+        "digest": digest,
+    }
+
+    # Allow future pushes to find this task before it completes
+    # Implementation in morphs
+    taskdesc["attributes"]["eager_indexes"] = [TARGET_CACHE_INDEX.format(**subs)]
diff --git a/taskcluster/gecko_taskgraph/util/chunking.py b/taskcluster/gecko_taskgraph/util/chunking.py
new file mode 100644
index 0000000000..2c6c429a2c
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/chunking.py
@@ -0,0 +1,315 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+"""Utility functions to handle test chunking."""
+
+import json
+import logging
+import os
+from abc import ABCMeta, abstractmethod
+
+from manifestparser import TestManifest
+from manifestparser.filters import chunk_by_runtime, tags
+from mozbuild.util import memoize
+from moztest.resolve import TEST_SUITES, TestManifestLoader, TestResolver
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.util.bugbug import CT_LOW, BugbugTimeoutException, push_schedules
+
+logger = logging.getLogger(__name__)
+here = os.path.abspath(os.path.dirname(__file__))
+resolver = TestResolver.from_environment(cwd=here, loader_cls=TestManifestLoader)
+
+
+def guess_mozinfo_from_task(task, repo=""):
+    """Attempt to build a mozinfo dict from a task definition.
+
+    This won't be perfect and many values used in the manifests will be missing. But
+    it should cover most of the major ones and be "good enough" for chunking in the
+    taskgraph.
+
+    Args:
+        task (dict): A task definition.
+
+    Returns:
+        A dict that can be used as a mozinfo replacement.
+    """
+    setting = task["test-setting"]
+    arch = setting["platform"]["arch"]
+    p_os = setting["platform"]["os"]
+
+    info = {
+        "asan": setting["build"].get("asan", False),
+        "bits": 32 if "32" in arch else 64,
+        "ccov": setting["build"].get("ccov", False),
+        "debug": setting["build"]["type"] in ("debug", "debug-isolated-process"),
+        "e10s": not setting["runtime"].get("1proc", False),
+        "no-fission": "no-fission" in setting["runtime"].keys(),
+        "fission": any(
+            "1proc" not in key or "no-fission" not in key
+            for key in setting["runtime"].keys()
+        ),
+        "headless": "-headless" in task["test-name"],
+        "condprof": "conditioned_profile" in setting["runtime"].keys(),
+        "tsan": setting["build"].get("tsan", False),
+        "xorigin": any("xorigin" in key for key in setting["runtime"].keys()),
+        "socketprocess_networking": "socketprocess_networking"
+        in setting["runtime"].keys(),
+        "nightly_build": repo in ["mozilla-central", "autoland", "try", ""],  # trunk
+        "http3": "http3" in setting["runtime"].keys(),
+    }
+    for platform in ("android", "linux", "mac", "win"):
+        if p_os["name"].startswith(platform):
+            info["os"] = platform
+            break
+    else:
+        raise ValueError("{} is not a known platform!".format(p_os["name"]))
+
+    # crashreporter is disabled for asan / tsan builds
+    if info["asan"] or info["tsan"]:
+        info["crashreporter"] = False
+    else:
+        info["crashreporter"] = True
+
+    info["appname"] = "fennec" if info["os"] == "android" else "firefox"
+
+    # guess processor
+    if arch == "aarch64":
+        info["processor"] = "aarch64"
+    elif info["os"] == "android" and "arm" in arch:
+        info["processor"] = "arm"
+    elif info["bits"] == 32:
+        info["processor"] = "x86"
+    else:
+        info["processor"] = "x86_64"
+
+    # guess toolkit
+    if info["os"] == "android":
+        info["toolkit"] = "android"
+    elif info["os"] == "win":
+        info["toolkit"] = "windows"
+    elif info["os"] == "mac":
+        info["toolkit"] = "cocoa"
+    else:
+        info["toolkit"] = "gtk"
+
+    # guess os_version
+    os_versions = {
+        ("linux", "1804"): "18.04",
+        ("macosx", "1015"): "10.15",
+        ("macosx", "1100"): "11.00",
+        ("windows", "7"): "6.1",
+        ("windows", "10"): "10.0",
+    }
+    for (name, old_ver), new_ver in os_versions.items():
+        if p_os["name"] == name and p_os["version"] == old_ver:
+            info["os_version"] = new_ver
+            break
+
+    return info
+
+
+@memoize
+def get_runtimes(platform, suite_name):
+    if not suite_name or not platform:
+        raise TypeError("suite_name and platform cannot be empty.")
+
+    base = os.path.join(GECKO, "testing", "runtimes", "manifest-runtimes-{}.json")
+    for key in ("android", "windows"):
+        if key in platform:
+            path = base.format(key)
+            break
+    else:
+        path = base.format("unix")
+
+    if not os.path.exists(path):
+        raise OSError(f"manifest runtime file at {path} not found.")
+
+    with open(path) as fh:
+        return json.load(fh)[suite_name]
+
+
+def chunk_manifests(suite, platform, chunks, manifests):
+    """Run the chunking algorithm.
+
+    Args:
+        platform (str): Platform used to find runtime info.
+        chunks (int): Number of chunks to split manifests into.
+        manifests(list): Manifests to chunk.
+
+    Returns:
+        A list of length `chunks` where each item contains a list of manifests
+        that run in that chunk.
+    """
+    manifests = set(manifests)
+
+    if "web-platform-tests" not in suite:
+        runtimes = {
+            k: v for k, v in get_runtimes(platform, suite).items() if k in manifests
+        }
+        return [
+            c[1]
+            for c in chunk_by_runtime(None, chunks, runtimes).get_chunked_manifests(
+                manifests
+            )
+        ]
+
+    # Keep track of test paths for each chunk, and the runtime information.
+    chunked_manifests = [[] for _ in range(chunks)]
+
+    # Spread out the test manifests evenly across all chunks.
+    for index, key in enumerate(sorted(manifests)):
+        chunked_manifests[index % chunks].append(key)
+
+    # One last sort by the number of manifests. Chunk size should be more or less
+    # equal in size.
+    chunked_manifests.sort(key=lambda x: len(x))
+
+    # Return just the chunked test paths.
+    return chunked_manifests
+
+
+class BaseManifestLoader(metaclass=ABCMeta):
+    def __init__(self, params):
+        self.params = params
+
+    @abstractmethod
+    def get_manifests(self, flavor, subsuite, mozinfo):
+        """Compute which manifests should run for the given flavor, subsuite and mozinfo.
+
+        This function returns skipped manifests separately so that more balanced
+        chunks can be achieved by only considering "active" manifests in the
+        chunking algorithm.
+
+        Args:
+            flavor (str): The suite to run. Values are defined by the 'build_flavor' key
+                in `moztest.resolve.TEST_SUITES`.
+            subsuite (str): The subsuite to run or 'undefined' to denote no subsuite.
+            mozinfo (frozenset): Set of data in the form of (<key>, <value>) used
+                                 for filtering.
+
+        Returns:
+            A tuple of two manifest lists. The first is the set of active manifests (will
+            run at least one test. The second is a list of skipped manifests (all tests are
+            skipped).
+        """
+
+
+class DefaultLoader(BaseManifestLoader):
+    """Load manifests using metadata from the TestResolver."""
+
+    @memoize
+    def get_tests(self, suite):
+        suite_definition = TEST_SUITES[suite]
+        return list(
+            resolver.resolve_tests(
+                flavor=suite_definition["build_flavor"],
+                subsuite=suite_definition.get("kwargs", {}).get(
+                    "subsuite", "undefined"
+                ),
+            )
+        )
+
+    @memoize
+    def get_manifests(self, suite, mozinfo):
+        mozinfo = dict(mozinfo)
+        # Compute all tests for the given suite/subsuite.
+        tests = self.get_tests(suite)
+
+        # TODO: the only exception here is we schedule webgpu as that is a --tag
+        if "web-platform-tests" in suite:
+            manifests = set()
+            for t in tests:
+                manifests.add(t["manifest"])
+            return {
+                "active": list(manifests),
+                "skipped": [],
+                "other_dirs": dict.fromkeys(manifests, ""),
+            }
+
+        manifests = {chunk_by_runtime.get_manifest(t) for t in tests}
+
+        filters = None
+        if mozinfo["condprof"]:
+            filters = [tags(["condprof"])]
+
+        # Compute  the active tests.
+        m = TestManifest()
+        m.tests = tests
+        tests = m.active_tests(disabled=False, exists=False, filters=filters, **mozinfo)
+        active = {}
+        # map manifests and 'other' directories included
+        for t in tests:
+            mp = chunk_by_runtime.get_manifest(t)
+            active.setdefault(mp, [])
+
+            if not mp.startswith(t["dir_relpath"]):
+                active[mp].append(t["dir_relpath"])
+
+        skipped = manifests - set(active.keys())
+        other = {}
+        for m in active:
+            if len(active[m]) > 0:
+                other[m] = list(set(active[m]))
+        return {
+            "active": list(active.keys()),
+            "skipped": list(skipped),
+            "other_dirs": other,
+        }
+
+
+class BugbugLoader(DefaultLoader):
+    """Load manifests using metadata from the TestResolver, and then
+    filter them based on a query to bugbug."""
+
+    CONFIDENCE_THRESHOLD = CT_LOW
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.timedout = False
+
+    @memoize
+    def get_manifests(self, suite, mozinfo):
+        manifests = super().get_manifests(suite, mozinfo)
+
+        # Don't prune any manifests if we're on a backstop push or there was a timeout.
+        if self.params["backstop"] or self.timedout:
+            return manifests
+
+        try:
+            data = push_schedules(self.params["project"], self.params["head_rev"])
+        except BugbugTimeoutException:
+            logger.warning("Timed out waiting for bugbug, loading all test manifests.")
+            self.timedout = True
+            return self.get_manifests(suite, mozinfo)
+
+        bugbug_manifests = {
+            m
+            for m, c in data.get("groups", {}).items()
+            if c >= self.CONFIDENCE_THRESHOLD
+        }
+
+        manifests["active"] = list(set(manifests["active"]) & bugbug_manifests)
+        manifests["skipped"] = list(set(manifests["skipped"]) & bugbug_manifests)
+        return manifests
+
+
+manifest_loaders = {
+    "bugbug": BugbugLoader,
+    "default": DefaultLoader,
+}
+
+_loader_cache = {}
+
+
+def get_manifest_loader(name, params):
+    # Ensure we never create more than one instance of the same loader type for
+    # performance reasons.
+    if name in _loader_cache:
+        return _loader_cache[name]
+
+    loader = manifest_loaders[name](dict(params))
+    _loader_cache[name] = loader
+    return loader
diff --git a/taskcluster/gecko_taskgraph/util/copy_task.py b/taskcluster/gecko_taskgraph/util/copy_task.py
new file mode 100644
index 0000000000..0aaf43361e
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/copy_task.py
@@ -0,0 +1,40 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from mozbuild.util import ReadOnlyDict
+from taskgraph.task import Task
+
+immutable_types = {int, float, bool, str, type(None), ReadOnlyDict}
+
+
+def copy_task(obj):
+    """
+    Perform a deep copy of a task that has a tree-like structure.
+
+    Unlike copy.deepcopy, this does *not* support copying graph-like structure,
+    but it does it more efficiently than deepcopy.
+    """
+    ty = type(obj)
+    if ty in immutable_types:
+        return obj
+    if ty is dict:
+        return {k: copy_task(v) for k, v in obj.items()}
+    if ty is list:
+        return [copy_task(elt) for elt in obj]
+    if ty is Task:
+        task = Task(
+            kind=copy_task(obj.kind),
+            label=copy_task(obj.label),
+            attributes=copy_task(obj.attributes),
+            task=copy_task(obj.task),
+            description=copy_task(obj.description),
+            optimization=copy_task(obj.optimization),
+            dependencies=copy_task(obj.dependencies),
+            soft_dependencies=copy_task(obj.soft_dependencies),
+            if_dependencies=copy_task(obj.if_dependencies),
+        )
+        if obj.task_id:
+            task.task_id = obj.task_id
+        return task
+    raise NotImplementedError(f"copying '{ty}' from '{obj}'")
diff --git a/taskcluster/gecko_taskgraph/util/declarative_artifacts.py b/taskcluster/gecko_taskgraph/util/declarative_artifacts.py
new file mode 100644
index 0000000000..545472dec3
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/declarative_artifacts.py
@@ -0,0 +1,92 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import re
+
+from gecko_taskgraph.util.scriptworker import (
+    generate_beetmover_artifact_map,
+    generate_beetmover_upstream_artifacts,
+)
+
+_ARTIFACT_ID_PER_PLATFORM = {
+    "android-aarch64-opt": "{package}-default-arm64-v8a",
+    "android-arm-opt": "{package}-default-armeabi-v7a",
+    "android-x86-opt": "{package}-default-x86",
+    "android-x86_64-opt": "{package}-default-x86_64",
+    "android-geckoview-fat-aar-opt": "{package}-default",
+    "android-aarch64-shippable": "{package}{update_channel}-omni-arm64-v8a",
+    "android-aarch64-shippable-lite": "{package}{update_channel}-arm64-v8a",
+    "android-arm-shippable": "{package}{update_channel}-omni-armeabi-v7a",
+    "android-arm-shippable-lite": "{package}{update_channel}-armeabi-v7a",
+    "android-x86-shippable": "{package}{update_channel}-omni-x86",
+    "android-x86-shippable-lite": "{package}{update_channel}-x86",
+    "android-x86_64-shippable": "{package}{update_channel}-omni-x86_64",
+    "android-x86_64-shippable-lite": "{package}{update_channel}-x86_64",
+    "android-geckoview-fat-aar-shippable": "{package}{update_channel}-omni",
+    "android-geckoview-fat-aar-shippable-lite": "{package}{update_channel}",
+}
+
+
+def get_geckoview_artifact_map(config, job):
+    return generate_beetmover_artifact_map(
+        config,
+        job,
+        **get_geckoview_template_vars(
+            config,
+            job["attributes"]["build_platform"],
+            job["maven-package"],
+            job["attributes"].get("update-channel"),
+        ),
+    )
+
+
+def get_geckoview_upstream_artifacts(config, job, package, platform=""):
+    if not platform:
+        platform = job["attributes"]["build_platform"]
+    upstream_artifacts = generate_beetmover_upstream_artifacts(
+        config,
+        job,
+        platform="",
+        **get_geckoview_template_vars(
+            config, platform, package, job["attributes"].get("update-channel")
+        ),
+    )
+    return [
+        {key: value for key, value in upstream_artifact.items() if key != "locale"}
+        for upstream_artifact in upstream_artifacts
+    ]
+
+
+def get_geckoview_template_vars(config, platform, package, update_channel):
+    version_groups = re.match(r"(\d+).(\d+).*", config.params["version"])
+    if version_groups:
+        major_version, minor_version = version_groups.groups()
+
+    return {
+        "artifact_id": get_geckoview_artifact_id(
+            config,
+            platform,
+            package,
+            update_channel,
+        ),
+        "build_date": config.params["moz_build_date"],
+        "major_version": major_version,
+        "minor_version": minor_version,
+    }
+
+
+def get_geckoview_artifact_id(config, platform, package, update_channel=None):
+    if update_channel == "release":
+        update_channel = ""
+    elif update_channel is not None:
+        update_channel = f"-{update_channel}"
+    else:
+        # For shippable builds, mozharness defaults to using
+        # "nightly-{project}" for the update channel.  For other builds, the
+        # update channel is not set, but the value is not substituted.
+        update_channel = "-nightly-{}".format(config.params["project"])
+    return _ARTIFACT_ID_PER_PLATFORM[platform].format(
+        update_channel=update_channel, package=package
+    )
diff --git a/taskcluster/gecko_taskgraph/util/docker.py b/taskcluster/gecko_taskgraph/util/docker.py
new file mode 100644
index 0000000000..e8de7d1fdb
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/docker.py
@@ -0,0 +1,333 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import hashlib
+import json
+import os
+import re
+import sys
+from collections.abc import Mapping
+from urllib.parse import quote, urlencode, urlunparse
+
+import requests
+import requests_unixsocket
+from mozbuild.util import memoize
+from mozpack.archive import create_tar_gz_from_files
+from mozpack.files import GeneratedFile
+from taskgraph.util.yaml import load_yaml
+
+from .. import GECKO
+
+IMAGE_DIR = os.path.join(GECKO, "taskcluster", "docker")
+
+
+def docker_url(path, **kwargs):
+    docker_socket = os.environ.get("DOCKER_SOCKET", "/var/run/docker.sock")
+    return urlunparse(
+        ("http+unix", quote(docker_socket, safe=""), path, "", urlencode(kwargs), "")
+    )
+
+
+def post_to_docker(tar, api_path, **kwargs):
+    """POSTs a tar file to a given docker API path.
+
+    The tar argument can be anything that can be passed to requests.post()
+    as data (e.g. iterator or file object).
+    The extra keyword arguments are passed as arguments to the docker API.
+    """
+    # requests-unixsocket doesn't honor requests timeouts
+    # See https://github.com/msabramo/requests-unixsocket/issues/44
+    # We have some large docker images that trigger the default timeout,
+    # so we increase the requests-unixsocket timeout here.
+    session = requests.Session()
+    session.mount(
+        requests_unixsocket.DEFAULT_SCHEME,
+        requests_unixsocket.UnixAdapter(timeout=120),
+    )
+    req = session.post(
+        docker_url(api_path, **kwargs),
+        data=tar,
+        stream=True,
+        headers={"Content-Type": "application/x-tar"},
+    )
+    if req.status_code != 200:
+        message = req.json().get("message")
+        if not message:
+            message = f"docker API returned HTTP code {req.status_code}"
+        raise Exception(message)
+    status_line = {}
+
+    buf = b""
+    for content in req.iter_content(chunk_size=None):
+        if not content:
+            continue
+        # Sometimes, a chunk of content is not a complete json, so we cumulate
+        # with leftovers from previous iterations.
+        buf += content
+        try:
+            data = json.loads(buf)
+        except Exception:
+            continue
+        buf = b""
+        # data is sometimes an empty dict.
+        if not data:
+            continue
+        # Mimick how docker itself presents the output. This code was tested
+        # with API version 1.18 and 1.26.
+        if "status" in data:
+            if "id" in data:
+                if sys.stderr.isatty():
+                    total_lines = len(status_line)
+                    line = status_line.setdefault(data["id"], total_lines)
+                    n = total_lines - line
+                    if n > 0:
+                        # Move the cursor up n lines.
+                        sys.stderr.write(f"\033[{n}A")
+                    # Clear line and move the cursor to the beginning of it.
+                    sys.stderr.write("\033[2K\r")
+                    sys.stderr.write(
+                        "{}: {} {}\n".format(
+                            data["id"], data["status"], data.get("progress", "")
+                        )
+                    )
+                    if n > 1:
+                        # Move the cursor down n - 1 lines, which, considering
+                        # the carriage return on the last write, gets us back
+                        # where we started.
+                        sys.stderr.write(f"\033[{n - 1}B")
+                else:
+                    status = status_line.get(data["id"])
+                    # Only print status changes.
+                    if status != data["status"]:
+                        sys.stderr.write("{}: {}\n".format(data["id"], data["status"]))
+                        status_line[data["id"]] = data["status"]
+            else:
+                status_line = {}
+                sys.stderr.write("{}\n".format(data["status"]))
+        elif "stream" in data:
+            sys.stderr.write(data["stream"])
+        elif "aux" in data:
+            sys.stderr.write(repr(data["aux"]))
+        elif "error" in data:
+            sys.stderr.write("{}\n".format(data["error"]))
+            # Sadly, docker doesn't give more than a plain string for errors,
+            # so the best we can do to propagate the error code from the command
+            # that failed is to parse the error message...
+            errcode = 1
+            m = re.search(r"returned a non-zero code: (\d+)", data["error"])
+            if m:
+                errcode = int(m.group(1))
+            sys.exit(errcode)
+        else:
+            raise NotImplementedError(repr(data))
+        sys.stderr.flush()
+
+
+def docker_image(name, by_tag=False):
+    """
+    Resolve in-tree prebuilt docker image to ``<registry>/<repository>@sha256:<digest>``,
+    or ``<registry>/<repository>:<tag>`` if `by_tag` is `True`.
+    """
+    try:
+        with open(os.path.join(IMAGE_DIR, name, "REGISTRY")) as f:
+            registry = f.read().strip()
+    except OSError:
+        with open(os.path.join(IMAGE_DIR, "REGISTRY")) as f:
+            registry = f.read().strip()
+
+    if not by_tag:
+        hashfile = os.path.join(IMAGE_DIR, name, "HASH")
+        try:
+            with open(hashfile) as f:
+                return f"{registry}/{name}@{f.read().strip()}"
+        except OSError:
+            raise Exception(f"Failed to read HASH file {hashfile}")
+
+    try:
+        with open(os.path.join(IMAGE_DIR, name, "VERSION")) as f:
+            tag = f.read().strip()
+    except OSError:
+        tag = "latest"
+    return f"{registry}/{name}:{tag}"
+
+
+class VoidWriter:
+    """A file object with write capabilities that does nothing with the written
+    data."""
+
+    def write(self, buf):
+        pass
+
+
+def generate_context_hash(topsrcdir, image_path, image_name, args):
+    """Generates a sha256 hash for context directory used to build an image."""
+
+    return stream_context_tar(
+        topsrcdir, image_path, VoidWriter(), image_name, args=args
+    )
+
+
+class HashingWriter:
+    """A file object with write capabilities that hashes the written data at
+    the same time it passes down to a real file object."""
+
+    def __init__(self, writer):
+        self._hash = hashlib.sha256()
+        self._writer = writer
+
+    def write(self, buf):
+        self._hash.update(buf)
+        self._writer.write(buf)
+
+    def hexdigest(self):
+        return self._hash.hexdigest()
+
+
+def create_context_tar(topsrcdir, context_dir, out_path, image_name, args):
+    """Create a context tarball.
+
+    A directory ``context_dir`` containing a Dockerfile will be assembled into
+    a gzipped tar file at ``out_path``.
+
+    We also scan the source Dockerfile for special syntax that influences
+    context generation.
+
+    If a line in the Dockerfile has the form ``# %include <path>``,
+    the relative path specified on that line will be matched against
+    files in the source repository and added to the context under the
+    path ``topsrcdir/``. If an entry is a directory, we add all files
+    under that directory.
+
+    Returns the SHA-256 hex digest of the created archive.
+    """
+    with open(out_path, "wb") as fh:
+        return stream_context_tar(
+            topsrcdir,
+            context_dir,
+            fh,
+            image_name=image_name,
+            args=args,
+        )
+
+
+def stream_context_tar(topsrcdir, context_dir, out_file, image_name, args):
+    """Like create_context_tar, but streams the tar file to the `out_file` file
+    object."""
+    archive_files = {}
+    content = []
+
+    context_dir = os.path.join(topsrcdir, context_dir)
+
+    for root, dirs, files in os.walk(context_dir):
+        for f in files:
+            source_path = os.path.join(root, f)
+            archive_path = source_path[len(context_dir) + 1 :]
+            archive_files[archive_path] = source_path
+
+    # Parse Dockerfile for special syntax of extra files to include.
+    with open(os.path.join(context_dir, "Dockerfile"), "r") as fh:
+        for line in fh:
+            content.append(line)
+
+            if not line.startswith("# %include"):
+                continue
+
+            p = line[len("# %include ") :].strip()
+            if os.path.isabs(p):
+                raise Exception("extra include path cannot be absolute: %s" % p)
+
+            fs_path = os.path.normpath(os.path.join(topsrcdir, p))
+            # Check for filesystem traversal exploits.
+            if not fs_path.startswith(topsrcdir):
+                raise Exception("extra include path outside topsrcdir: %s" % p)
+
+            if not os.path.exists(fs_path):
+                raise Exception("extra include path does not exist: %s" % p)
+
+            if os.path.isdir(fs_path):
+                for root, dirs, files in os.walk(fs_path):
+                    for f in files:
+                        source_path = os.path.join(root, f)
+                        rel = source_path[len(fs_path) + 1 :]
+                        archive_path = os.path.join("topsrcdir", p, rel)
+                        archive_files[archive_path] = source_path
+            else:
+                archive_path = os.path.join("topsrcdir", p)
+                archive_files[archive_path] = fs_path
+
+    archive_files["Dockerfile"] = GeneratedFile("".join(content).encode("utf-8"))
+
+    writer = HashingWriter(out_file)
+    create_tar_gz_from_files(writer, archive_files, f"{image_name}.tar")
+    return writer.hexdigest()
+
+
+class ImagePathsMap(Mapping):
+    """ImagePathsMap contains the mapping of Docker image names to their
+    context location in the filesystem. The register function allows Thunderbird
+    to define additional images under comm/taskcluster.
+    """
+
+    def __init__(self, config_path, image_dir=IMAGE_DIR):
+        config = load_yaml(GECKO, config_path)
+        self.__update_image_paths(config["jobs"], image_dir)
+
+    def __getitem__(self, key):
+        return self.__dict__[key]
+
+    def __iter__(self):
+        return iter(self.__dict__)
+
+    def __len__(self):
+        return len(self.__dict__)
+
+    def __update_image_paths(self, jobs, image_dir):
+        self.__dict__.update(
+            {
+                k: os.path.join(image_dir, v.get("definition", k))
+                for k, v in jobs.items()
+            }
+        )
+
+    def register(self, jobs_config_path, image_dir):
+        """Register additional image_paths. In this case, there is no 'jobs'
+        key in the loaded YAML as this file is loaded via jobs-from in kind.yml."""
+        jobs = load_yaml(GECKO, jobs_config_path)
+        self.__update_image_paths(jobs, image_dir)
+
+
+image_paths = ImagePathsMap("taskcluster/ci/docker-image/kind.yml")
+
+
+def image_path(name):
+    if name in image_paths:
+        return image_paths[name]
+    return os.path.join(IMAGE_DIR, name)
+
+
+@memoize
+def parse_volumes(image):
+    """Parse VOLUME entries from a Dockerfile for an image."""
+    volumes = set()
+
+    path = image_path(image)
+
+    with open(os.path.join(path, "Dockerfile"), "rb") as fh:
+        for line in fh:
+            line = line.strip()
+            # We assume VOLUME definitions don't use ARGS.
+            if not line.startswith(b"VOLUME "):
+                continue
+
+            v = line.split(None, 1)[1]
+            if v.startswith(b"["):
+                raise ValueError(
+                    "cannot parse array syntax for VOLUME; "
+                    "convert to multiple entries"
+                )
+
+            volumes |= {v.decode("utf-8") for v in v.split()}
+
+    return volumes
diff --git a/taskcluster/gecko_taskgraph/util/hash.py b/taskcluster/gecko_taskgraph/util/hash.py
new file mode 100644
index 0000000000..485c9a7c48
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/hash.py
@@ -0,0 +1,68 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import hashlib
+
+import mozpack.path as mozpath
+from mozbuild.util import memoize
+from mozversioncontrol import get_repository_object
+
+
+@memoize
+def hash_path(path):
+    """Hash a single file.
+
+    Returns the SHA-256 hash in hex form.
+    """
+    with open(path, mode="rb") as fh:
+        return hashlib.sha256(fh.read()).hexdigest()
+
+
+@memoize
+def get_file_finder(base_path):
+    from pathlib import Path
+
+    repo = get_repository_object(base_path)
+    if repo:
+        files = repo.get_tracked_files_finder(base_path)
+        if files:
+            return files
+        else:
+            return None
+    else:
+        return get_repository_object(Path(base_path)).get_tracked_files_finder(
+            base_path
+        )
+
+
+def hash_paths(base_path, patterns):
+    """
+    Give a list of path patterns, return a digest of the contents of all
+    the corresponding files, similarly to git tree objects or mercurial
+    manifests.
+
+    Each file is hashed. The list of all hashes and file paths is then
+    itself hashed to produce the result.
+    """
+    finder = get_file_finder(base_path)
+    h = hashlib.sha256()
+    files = {}
+    if finder:
+        for pattern in patterns:
+            found = list(finder.find(pattern))
+            if found:
+                files.update(found)
+            else:
+                raise Exception("%s did not match anything" % pattern)
+        for path in sorted(files.keys()):
+            if path.endswith((".pyc", ".pyd", ".pyo")):
+                continue
+            h.update(
+                "{} {}\n".format(
+                    hash_path(mozpath.abspath(mozpath.join(base_path, path))),
+                    mozpath.normsep(path),
+                ).encode("utf-8")
+            )
+
+    return h.hexdigest()
diff --git a/taskcluster/gecko_taskgraph/util/hg.py b/taskcluster/gecko_taskgraph/util/hg.py
new file mode 100644
index 0000000000..18a92fbd0d
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/hg.py
@@ -0,0 +1,139 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import subprocess
+
+import requests
+from mozbuild.util import memoize
+from redo import retry
+
+logger = logging.getLogger(__name__)
+
+PUSHLOG_CHANGESET_TMPL = (
+    "{repository}/json-pushes?version=2&changeset={revision}&tipsonly=1"
+)
+PUSHLOG_PUSHES_TMPL = (
+    "{repository}/json-pushes/?version=2&startID={push_id_start}&endID={push_id_end}"
+)
+
+
+def _query_pushlog(url):
+    response = retry(
+        requests.get,
+        attempts=5,
+        sleeptime=10,
+        args=(url,),
+        kwargs={"timeout": 60, "headers": {"User-Agent": "TaskCluster"}},
+    )
+
+    return response.json()["pushes"]
+
+
+def find_hg_revision_push_info(repository, revision):
+    """Given the parameters for this action and a revision, find the
+    pushlog_id of the revision."""
+    url = PUSHLOG_CHANGESET_TMPL.format(repository=repository, revision=revision)
+
+    pushes = _query_pushlog(url)
+
+    if len(pushes) != 1:
+        raise RuntimeError(
+            "Found {} pushlog_ids, expected 1, for {} revision {}: {}".format(
+                len(pushes), repository, revision, pushes
+            )
+        )
+
+    pushid = list(pushes.keys())[0]
+    return {
+        "pushdate": pushes[pushid]["date"],
+        "pushid": pushid,
+        "user": pushes[pushid]["user"],
+    }
+
+
+@memoize
+def get_push_data(repository, project, push_id_start, push_id_end):
+    url = PUSHLOG_PUSHES_TMPL.format(
+        repository=repository,
+        push_id_start=push_id_start - 1,
+        push_id_end=push_id_end,
+    )
+
+    try:
+        pushes = _query_pushlog(url)
+
+        return {
+            push_id: pushes[str(push_id)]
+            for push_id in range(push_id_start, push_id_end + 1)
+        }
+
+    # In the event of request times out, requests will raise a TimeoutError.
+    except requests.exceptions.Timeout:
+        logger.warning("json-pushes timeout")
+
+    # In the event of a network problem (e.g. DNS failure, refused connection, etc),
+    # requests will raise a ConnectionError.
+    except requests.exceptions.ConnectionError:
+        logger.warning("json-pushes connection error")
+
+    # In the event of the rare invalid HTTP response(e.g 404, 401),
+    # requests will raise an HTTPError exception
+    except requests.exceptions.HTTPError:
+        logger.warning("Bad Http response")
+
+    # When we get invalid JSON (i.e. 500 error), it results in a ValueError (bug 1313426)
+    except ValueError as error:
+        logger.warning(f"Invalid JSON, possible server error: {error}")
+
+    # We just print the error out as a debug message if we failed to catch the exception above
+    except requests.exceptions.RequestException as error:
+        logger.warning(error)
+
+    return None
+
+
+@memoize
+def get_json_automationrelevance(repository, revision):
+    url = "{}/json-automationrelevance/{}".format(repository.rstrip("/"), revision)
+    logger.debug("Querying version control for metadata: %s", url)
+
+    def get_automationrelevance():
+        response = requests.get(url, timeout=30)
+        return response.json()
+
+    return retry(get_automationrelevance, attempts=10, sleeptime=10)
+
+
+def get_hg_revision_branch(root, revision):
+    """Given the parameters for a revision, find the hg_branch (aka
+    relbranch) of the revision."""
+    return subprocess.check_output(
+        [
+            "hg",
+            "identify",
+            "-T",
+            "{branch}",
+            "--rev",
+            revision,
+        ],
+        cwd=root,
+        universal_newlines=True,
+    )
+
+
+# For these functions, we assume that run-task has correctly checked out the
+# revision indicated by GECKO_HEAD_REF, so all that remains is to see what the
+# current revision is.  Mercurial refers to that as `.`.
+def get_hg_commit_message(root, rev="."):
+    return subprocess.check_output(
+        ["hg", "log", "-r", rev, "-T", "{desc}"], cwd=root, universal_newlines=True
+    )
+
+
+def calculate_head_rev(root):
+    return subprocess.check_output(
+        ["hg", "log", "-r", ".", "-T", "{node}"], cwd=root, universal_newlines=True
+    )
diff --git a/taskcluster/gecko_taskgraph/util/partials.py b/taskcluster/gecko_taskgraph/util/partials.py
new file mode 100644
index 0000000000..1a3affcc42
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/partials.py
@@ -0,0 +1,297 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+
+import redo
+import requests
+
+from gecko_taskgraph.util.scriptworker import (
+    BALROG_SCOPE_ALIAS_TO_PROJECT,
+    BALROG_SERVER_SCOPES,
+)
+
+logger = logging.getLogger(__name__)
+
+PLATFORM_RENAMES = {
+    "windows2012-32": "win32",
+    "windows2012-64": "win64",
+    "windows2012-aarch64": "win64-aarch64",
+    "osx-cross": "macosx64",
+    "osx": "macosx64",
+}
+
+BALROG_PLATFORM_MAP = {
+    "linux": ["Linux_x86-gcc3"],
+    "linux32": ["Linux_x86-gcc3"],
+    "linux64": ["Linux_x86_64-gcc3"],
+    "linux64-asan-reporter": ["Linux_x86_64-gcc3-asan"],
+    "macosx64": [
+        "Darwin_x86_64-gcc3-u-i386-x86_64",
+        "Darwin_x86-gcc3-u-i386-x86_64",
+        "Darwin_aarch64-gcc3",
+        "Darwin_x86-gcc3",
+        "Darwin_x86_64-gcc3",
+    ],
+    "win32": ["WINNT_x86-msvc", "WINNT_x86-msvc-x86", "WINNT_x86-msvc-x64"],
+    "win64": ["WINNT_x86_64-msvc", "WINNT_x86_64-msvc-x64"],
+    "win64-asan-reporter": ["WINNT_x86_64-msvc-x64-asan"],
+    "win64-aarch64": [
+        "WINNT_aarch64-msvc-aarch64",
+    ],
+}
+
+FTP_PLATFORM_MAP = {
+    "Darwin_x86-gcc3": "mac",
+    "Darwin_x86-gcc3-u-i386-x86_64": "mac",
+    "Darwin_x86_64-gcc3": "mac",
+    "Darwin_x86_64-gcc3-u-i386-x86_64": "mac",
+    "Darwin_aarch64-gcc3": "mac",
+    "Linux_x86-gcc3": "linux-i686",
+    "Linux_x86_64-gcc3": "linux-x86_64",
+    "Linux_x86_64-gcc3-asan": "linux-x86_64-asan-reporter",
+    "WINNT_x86_64-msvc-x64-asan": "win64-asan-reporter",
+    "WINNT_x86-msvc": "win32",
+    "WINNT_x86-msvc-x64": "win32",
+    "WINNT_x86-msvc-x86": "win32",
+    "WINNT_x86_64-msvc": "win64",
+    "WINNT_x86_64-msvc-x64": "win64",
+    "WINNT_aarch64-msvc-aarch64": "win64-aarch64",
+}
+
+
+def get_balrog_platform_name(platform):
+    """Convert build platform names into balrog platform names.
+
+    Remove known values instead to catch aarch64 and other platforms
+    that may be added.
+    """
+    removals = ["-devedition", "-shippable"]
+    for remove in removals:
+        platform = platform.replace(remove, "")
+    return PLATFORM_RENAMES.get(platform, platform)
+
+
+def _sanitize_platform(platform):
+    platform = get_balrog_platform_name(platform)
+    if platform not in BALROG_PLATFORM_MAP:
+        return platform
+    return BALROG_PLATFORM_MAP[platform][0]
+
+
+def get_builds(release_history, platform, locale):
+    """Examine cached balrog release history and return the list of
+    builds we need to generate diffs from"""
+    platform = _sanitize_platform(platform)
+    return release_history.get(platform, {}).get(locale, {})
+
+
+def get_partials_artifacts_from_params(release_history, platform, locale):
+    platform = _sanitize_platform(platform)
+    return [
+        (artifact, details.get("previousVersion", None))
+        for artifact, details in release_history.get(platform, {})
+        .get(locale, {})
+        .items()
+    ]
+
+
+def get_partials_info_from_params(release_history, platform, locale):
+    platform = _sanitize_platform(platform)
+
+    artifact_map = {}
+    for k in release_history.get(platform, {}).get(locale, {}):
+        details = release_history[platform][locale][k]
+        attributes = ("buildid", "previousBuildNumber", "previousVersion")
+        artifact_map[k] = {
+            attr: details[attr] for attr in attributes if attr in details
+        }
+    return artifact_map
+
+
+def _retry_on_http_errors(url, verify, params, errors):
+    if params:
+        params_str = "&".join("=".join([k, str(v)]) for k, v in params.items())
+    else:
+        params_str = ""
+    logger.info("Connecting to %s?%s", url, params_str)
+    for _ in redo.retrier(sleeptime=5, max_sleeptime=30, attempts=10):
+        try:
+            req = requests.get(url, verify=verify, params=params, timeout=10)
+            req.raise_for_status()
+            return req
+        except requests.HTTPError as e:
+            if e.response.status_code in errors:
+                logger.exception(
+                    "Got HTTP %s trying to reach %s", e.response.status_code, url
+                )
+            else:
+                raise
+    else:
+        raise Exception(f"Cannot connect to {url}!")
+
+
+def get_sorted_releases(product, branch):
+    """Returns a list of release names from Balrog.
+    :param product: product name, AKA appName
+    :param branch: branch name, e.g. mozilla-central
+    :return: a sorted list of release names, most recent first.
+    """
+    url = f"{_get_balrog_api_root(branch)}/releases"
+    params = {
+        "product": product,
+        # Adding -nightly-2 (2 stands for the beginning of build ID
+        # based on date) should filter out release and latest blobs.
+        # This should be changed to -nightly-3 in 3000 ;)
+        "name_prefix": f"{product}-{branch}-nightly-2",
+        "names_only": True,
+    }
+    req = _retry_on_http_errors(url=url, verify=True, params=params, errors=[500])
+    releases = req.json()["names"]
+    releases = sorted(releases, reverse=True)
+    return releases
+
+
+def get_release_builds(release, branch):
+    url = f"{_get_balrog_api_root(branch)}/releases/{release}"
+    req = _retry_on_http_errors(url=url, verify=True, params=None, errors=[500])
+    return req.json()
+
+
+def _get_balrog_api_root(branch):
+    # Query into the scopes scriptworker uses to make sure we check against the same balrog server
+    # That our jobs would use.
+    scope = None
+    for alias, projects in BALROG_SCOPE_ALIAS_TO_PROJECT:
+        if branch in projects and alias in BALROG_SERVER_SCOPES:
+            scope = BALROG_SERVER_SCOPES[alias]
+            break
+    else:
+        scope = BALROG_SERVER_SCOPES["default"]
+
+    if scope == "balrog:server:dep":
+        return "https://stage.balrog.nonprod.cloudops.mozgcp.net/api/v1"
+    return "https://aus5.mozilla.org/api/v1"
+
+
+def find_localtest(fileUrls):
+    for channel in fileUrls:
+        if "-localtest" in channel:
+            return channel
+
+
+def populate_release_history(
+    product, branch, maxbuilds=4, maxsearch=10, partial_updates=None
+):
+    # Assuming we are using release branches when we know the list of previous
+    # releases in advance
+    if partial_updates is not None:
+        return _populate_release_history(
+            product, branch, partial_updates=partial_updates
+        )
+    return _populate_nightly_history(
+        product, branch, maxbuilds=maxbuilds, maxsearch=maxsearch
+    )
+
+
+def _populate_nightly_history(product, branch, maxbuilds=4, maxsearch=10):
+    """Find relevant releases in Balrog
+    Not all releases have all platforms and locales, due
+    to Taskcluster migration.
+
+        Args:
+            product (str): capitalized product name, AKA appName, e.g. Firefox
+            branch (str): branch name (mozilla-central)
+            maxbuilds (int): Maximum number of historical releases to populate
+            maxsearch(int): Traverse at most this many releases, to avoid
+                working through the entire history.
+        Returns:
+            json object based on data from balrog api
+
+            results = {
+                'platform1': {
+                    'locale1': {
+                        'buildid1': mar_url,
+                        'buildid2': mar_url,
+                        'buildid3': mar_url,
+                    },
+                    'locale2': {
+                        'target.partial-1.mar': {'buildid1': 'mar_url'},
+                    }
+                },
+                'platform2': {
+                }
+            }
+    """
+    last_releases = get_sorted_releases(product, branch)
+
+    partial_mar_tmpl = "target.partial-{}.mar"
+
+    builds = dict()
+    for release in last_releases[:maxsearch]:
+        # maxbuilds in all categories, don't make any more queries
+        full = len(builds) > 0 and all(
+            len(builds[platform][locale]) >= maxbuilds
+            for platform in builds
+            for locale in builds[platform]
+        )
+        if full:
+            break
+        history = get_release_builds(release, branch)
+
+        for platform in history["platforms"]:
+            if "alias" in history["platforms"][platform]:
+                continue
+            if platform not in builds:
+                builds[platform] = dict()
+            for locale in history["platforms"][platform]["locales"]:
+                if locale not in builds[platform]:
+                    builds[platform][locale] = dict()
+                if len(builds[platform][locale]) >= maxbuilds:
+                    continue
+                buildid = history["platforms"][platform]["locales"][locale]["buildID"]
+                url = history["platforms"][platform]["locales"][locale]["completes"][0][
+                    "fileUrl"
+                ]
+                nextkey = len(builds[platform][locale]) + 1
+                builds[platform][locale][partial_mar_tmpl.format(nextkey)] = {
+                    "buildid": buildid,
+                    "mar_url": url,
+                }
+    return builds
+
+
+def _populate_release_history(product, branch, partial_updates):
+    builds = dict()
+    for version, release in partial_updates.items():
+        prev_release_blob = "{product}-{version}-build{build_number}".format(
+            product=product, version=version, build_number=release["buildNumber"]
+        )
+        partial_mar_key = f"target-{version}.partial.mar"
+        history = get_release_builds(prev_release_blob, branch)
+        # use one of the localtest channels to avoid relying on bouncer
+        localtest = find_localtest(history["fileUrls"])
+        url_pattern = history["fileUrls"][localtest]["completes"]["*"]
+
+        for platform in history["platforms"]:
+            if "alias" in history["platforms"][platform]:
+                continue
+            if platform not in builds:
+                builds[platform] = dict()
+            for locale in history["platforms"][platform]["locales"]:
+                if locale not in builds[platform]:
+                    builds[platform][locale] = dict()
+                buildid = history["platforms"][platform]["locales"][locale]["buildID"]
+                url = url_pattern.replace(
+                    "%OS_FTP%", FTP_PLATFORM_MAP[platform]
+                ).replace("%LOCALE%", locale)
+                builds[platform][locale][partial_mar_key] = {
+                    "buildid": buildid,
+                    "mar_url": url,
+                    "previousVersion": version,
+                    "previousBuildNumber": release["buildNumber"],
+                    "product": product,
+                }
+    return builds
diff --git a/taskcluster/gecko_taskgraph/util/partners.py b/taskcluster/gecko_taskgraph/util/partners.py
new file mode 100644
index 0000000000..2546e1ae88
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/partners.py
@@ -0,0 +1,555 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import json
+import logging
+import os
+import xml.etree.ElementTree as ET
+from urllib.parse import urlencode
+
+import requests
+import yaml
+from redo import retry
+from taskgraph.util.schema import resolve_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level
+from gecko_taskgraph.util.copy_task import copy_task
+
+# Suppress chatty requests logging
+logging.getLogger("requests").setLevel(logging.WARNING)
+
+log = logging.getLogger(__name__)
+
+GITHUB_API_ENDPOINT = "https://api.github.com/graphql"
+
+"""
+LOGIN_QUERY, MANIFEST_QUERY, and REPACK_CFG_QUERY are all written to the Github v4 API,
+which users GraphQL. See https://developer.github.com/v4/
+"""
+
+LOGIN_QUERY = """query {
+  viewer {
+    login
+    name
+  }
+}
+"""
+
+# Returns the contents of default.xml from a manifest repository
+MANIFEST_QUERY = """query {
+  repository(owner:"%(owner)s", name:"%(repo)s") {
+    object(expression: "master:%(file)s") {
+      ... on Blob {
+        text
+      }
+    }
+  }
+}
+"""
+# Example response:
+# {
+#   "data": {
+#     "repository": {
+#       "object": {
+#         "text": "<?xml version=\"1.0\" ?>\n<manifest>\n  " +
+#           "<remote fetch=\"git@github.com:mozilla-partners/\" name=\"mozilla-partners\"/>\n  " +
+#           "<remote fetch=\"git@github.com:mozilla/\" name=\"mozilla\"/>\n\n  " +
+#           "<project name=\"repack-scripts\" path=\"scripts\" remote=\"mozilla-partners\" " +
+#           "revision=\"master\"/>\n  <project name=\"build-tools\" path=\"scripts/tools\" " +
+#           "remote=\"mozilla\" revision=\"master\"/>\n  <project name=\"mozilla-EME-free\" " +
+#           "path=\"partners/mozilla-EME-free\" remote=\"mozilla-partners\" " +
+#           "revision=\"master\"/>\n</manifest>\n"
+#       }
+#     }
+#   }
+# }
+
+# Returns the contents of desktop/*/repack.cfg for a partner repository
+REPACK_CFG_QUERY = """query{
+  repository(owner:"%(owner)s", name:"%(repo)s") {
+    object(expression: "%(revision)s:desktop/"){
+      ... on Tree {
+        entries {
+          name
+          object {
+            ... on Tree {
+              entries {
+                name
+                object {
+                  ... on Blob {
+                    text
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}
+"""
+# Example response:
+# {
+#   "data": {
+#     "repository": {
+#       "object": {
+#         "entries": [
+#           {
+#             "name": "mozilla-EME-free",
+#             "object": {
+#               "entries": [
+#                 {
+#                   "name": "distribution",
+#                   "object": {}
+#                 },
+#                 {
+#                   "name": "repack.cfg",
+#                   "object": {
+#                     "text": "aus=\"mozilla-EMEfree\"\ndist_id=\"mozilla-EMEfree\"\n" +
+#                             "dist_version=\"1.0\"\nlinux-i686=true\nlinux-x86_64=true\n" +
+#                             " locales=\"ach af de en-US\"\nmac=true\nwin32=true\nwin64=true\n" +
+#                             "output_dir=\"%(platform)s-EME-free/%(locale)s\"\n\n" +
+#                             "# Upload params\nbucket=\"net-mozaws-prod-delivery-firefox\"\n" +
+#                             "upload_to_candidates=true\n"
+#                   }
+#                 }
+#               ]
+#             }
+#           }
+#         ]
+#       }
+#     }
+#   }
+# }
+
+# Map platforms in repack.cfg into their equivalents in taskcluster
+TC_PLATFORM_PER_FTP = {
+    "linux-i686": "linux-shippable",
+    "linux-x86_64": "linux64-shippable",
+    "mac": "macosx64-shippable",
+    "win32": "win32-shippable",
+    "win64": "win64-shippable",
+    "win64-aarch64": "win64-aarch64-shippable",
+}
+
+TASKCLUSTER_PROXY_SECRET_ROOT = "http://taskcluster/secrets/v1/secret"
+
+LOCALES_FILE = os.path.join(
+    os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(__file__)))),
+    "browser",
+    "locales",
+    "l10n-changesets.json",
+)
+
+# cache data at the module level
+partner_configs = {}
+
+
+def get_token(params):
+    """We use a Personal Access Token from Github to lookup partner config. No extra scopes are
+    needed on the token to read public repositories, but need the 'repo' scope to see private
+    repositories. This is not fine grained and also grants r/w access, but is revoked at the repo
+    level.
+    """
+
+    # Allow for local taskgraph debugging
+    if os.environ.get("GITHUB_API_TOKEN"):
+        return os.environ["GITHUB_API_TOKEN"]
+
+    # The 'usual' method - via taskClusterProxy for decision tasks
+    url = "{secret_root}/project/releng/gecko/build/level-{level}/partner-github-api".format(
+        secret_root=TASKCLUSTER_PROXY_SECRET_ROOT, **params
+    )
+    try:
+        resp = retry(
+            requests.get,
+            attempts=2,
+            sleeptime=10,
+            args=(url,),
+            kwargs={"timeout": 60, "headers": ""},
+        )
+        j = resp.json()
+        return j["secret"]["key"]
+    except (requests.ConnectionError, ValueError, KeyError):
+        raise RuntimeError("Could not get Github API token to lookup partner data")
+
+
+def query_api(query, token):
+    """Make a query with a Github auth header, returning the json"""
+    headers = {"Authorization": "bearer %s" % token}
+    r = requests.post(GITHUB_API_ENDPOINT, json={"query": query}, headers=headers)
+    r.raise_for_status()
+
+    j = r.json()
+    if "errors" in j:
+        raise RuntimeError("Github query error - %s", j["errors"])
+    return j
+
+
+def check_login(token):
+    log.debug("Checking we have a valid login")
+    query_api(LOGIN_QUERY, token)
+
+
+def get_repo_params(repo):
+    """Parse the organisation and repo name from an https or git url for a repo"""
+    if repo.startswith("https"):
+        # eg https://github.com/mozilla-partners/mozilla-EME-free
+        return repo.rsplit("/", 2)[-2:]
+    if repo.startswith("git@"):
+        # eg git@github.com:mozilla-partners/mailru.git
+        repo = repo.replace(".git", "")
+        return repo.split(":")[-1].split("/")
+
+
+def get_partners(manifestRepo, token):
+    """Given the url to a manifest repository, retrieve the default.xml and parse it into a
+    list of partner repos.
+    """
+    log.debug("Querying for manifest default.xml in %s", manifestRepo)
+    owner, repo = get_repo_params(manifestRepo)
+    query = MANIFEST_QUERY % {"owner": owner, "repo": repo, "file": "default.xml"}
+    raw_manifest = query_api(query, token)
+    log.debug("Raw manifest: %s", raw_manifest)
+    if not raw_manifest["data"]["repository"]:
+        raise RuntimeError(
+            "Couldn't load partner manifest at %s, insufficient permissions ?"
+            % manifestRepo
+        )
+    e = ET.fromstring(raw_manifest["data"]["repository"]["object"]["text"])
+
+    remotes = {}
+    partners = {}
+    for child in e:
+        if child.tag == "remote":
+            name = child.attrib["name"]
+            url = child.attrib["fetch"]
+            remotes[name] = url
+            log.debug("Added remote %s at %s", name, url)
+        elif child.tag == "project":
+            # we don't need to check any code repos
+            if "scripts" in child.attrib["path"]:
+                continue
+            owner, _ = get_repo_params(remotes[child.attrib["remote"]] + "_")
+            partner_url = {
+                "owner": owner,
+                "repo": child.attrib["name"],
+                "revision": child.attrib["revision"],
+            }
+            partners[child.attrib["name"]] = partner_url
+            log.debug(
+                "Added partner %s at revision %s"
+                % (partner_url["repo"], partner_url["revision"])
+            )
+    return partners
+
+
+def parse_config(data):
+    """Parse a single repack.cfg file into a python dictionary.
+    data is contents of the file, in "foo=bar\nbaz=buzz" style. We do some translation on
+    locales and platforms data, otherwise passthrough
+    """
+    ALLOWED_KEYS = (
+        "locales",
+        "platforms",
+        "upload_to_candidates",
+        "repack_stub_installer",
+        "publish_to_releases",
+    )
+    config = {"platforms": []}
+    for l in data.splitlines():
+        if "=" in l:
+            l = str(l)
+            key, value = l.split("=", 1)
+            value = value.strip("'\"").rstrip("'\"")
+            if key in TC_PLATFORM_PER_FTP.keys():
+                if value.lower() == "true":
+                    config["platforms"].append(TC_PLATFORM_PER_FTP[key])
+                continue
+            if key not in ALLOWED_KEYS:
+                continue
+            if key == "locales":
+                # a list please
+                value = value.split(" ")
+            config[key] = value
+    return config
+
+
+def get_repack_configs(repackRepo, token):
+    """For a partner repository, retrieve all the repack.cfg files and parse them into a dict"""
+    log.debug("Querying for configs in %s", repackRepo)
+    query = REPACK_CFG_QUERY % repackRepo
+    raw_configs = query_api(query, token)
+    raw_configs = raw_configs["data"]["repository"]["object"]["entries"]
+
+    configs = {}
+    for sub_config in raw_configs:
+        name = sub_config["name"]
+        for file in sub_config["object"].get("entries", []):
+            if file["name"] != "repack.cfg":
+                continue
+            configs[name] = parse_config(file["object"]["text"])
+    return configs
+
+
+def get_attribution_config(manifestRepo, token):
+    log.debug("Querying for manifest attribution_config.yml in %s", manifestRepo)
+    owner, repo = get_repo_params(manifestRepo)
+    query = MANIFEST_QUERY % {
+        "owner": owner,
+        "repo": repo,
+        "file": "attribution_config.yml",
+    }
+    raw_manifest = query_api(query, token)
+    if not raw_manifest["data"]["repository"]:
+        raise RuntimeError(
+            "Couldn't load partner manifest at %s, insufficient permissions ?"
+            % manifestRepo
+        )
+    # no file has been set up, gracefully continue
+    if raw_manifest["data"]["repository"]["object"] is None:
+        log.debug("No attribution_config.yml file found")
+        return {}
+
+    return yaml.safe_load(raw_manifest["data"]["repository"]["object"]["text"])
+
+
+def get_partner_config_by_url(manifest_url, kind, token, partner_subset=None):
+    """Retrieve partner data starting from the manifest url, which points to a repository
+    containing a default.xml that is intended to be drive the Google tool 'repo'. It
+    descends into each partner repo to lookup and parse the repack.cfg file(s).
+
+    If partner_subset is a list of sub_config names only return data for those.
+
+    Supports caching data by kind to avoid repeated requests, relying on the related kinds for
+    partner repacking, signing, repackage, repackage signing all having the same kind prefix.
+    """
+    if not manifest_url:
+        raise RuntimeError(f"Manifest url for {kind} not defined")
+    if kind not in partner_configs:
+        log.info("Looking up data for %s from %s", kind, manifest_url)
+        check_login(token)
+        if kind == "release-partner-attribution":
+            partner_configs[kind] = get_attribution_config(manifest_url, token)
+        else:
+            partners = get_partners(manifest_url, token)
+
+            partner_configs[kind] = {}
+            for partner, partner_url in partners.items():
+                if partner_subset and partner not in partner_subset:
+                    continue
+                partner_configs[kind][partner] = get_repack_configs(partner_url, token)
+
+    return partner_configs[kind]
+
+
+def check_if_partners_enabled(config, tasks):
+    if (
+        (
+            config.params["release_enable_partner_repack"]
+            and config.kind.startswith("release-partner-repack")
+        )
+        or (
+            config.params["release_enable_partner_attribution"]
+            and config.kind.startswith("release-partner-attribution")
+        )
+        or (
+            config.params["release_enable_emefree"]
+            and config.kind.startswith("release-eme-free-")
+        )
+    ):
+        yield from tasks
+
+
+def get_partner_config_by_kind(config, kind):
+    """Retrieve partner data starting from the manifest url, which points to a repository
+    containing a default.xml that is intended to be drive the Google tool 'repo'. It
+    descends into each partner repo to lookup and parse the repack.cfg file(s).
+
+    Supports caching data by kind to avoid repeated requests, relying on the related kinds for
+    partner repacking, signing, repackage, repackage signing all having the same kind prefix.
+    """
+    partner_subset = config.params["release_partners"]
+    partner_configs = config.params["release_partner_config"] or {}
+
+    # TODO eme-free should be a partner; we shouldn't care about per-kind
+    for k in partner_configs:
+        if kind.startswith(k):
+            kind_config = partner_configs[k]
+            break
+    else:
+        return {}
+    # if we're only interested in a subset of partners we remove the rest
+    if partner_subset:
+        if kind.startswith("release-partner-repack"):
+            # TODO - should be fatal to have an unknown partner in partner_subset
+            for partner in [p for p in kind_config.keys() if p not in partner_subset]:
+                del kind_config[partner]
+        elif kind.startswith("release-partner-attribution") and isinstance(
+            kind_config, dict
+        ):
+            all_configs = copy_task(kind_config.get("configs", []))
+            kind_config["configs"] = []
+            for this_config in all_configs:
+                if this_config["campaign"] in partner_subset:
+                    kind_config["configs"].append(this_config)
+    return kind_config
+
+
+def _fix_subpartner_locales(orig_config, all_locales):
+    subpartner_config = copy_task(orig_config)
+    # Get an ordered list of subpartner locales that is a subset of all_locales
+    subpartner_config["locales"] = sorted(
+        list(set(orig_config["locales"]) & set(all_locales))
+    )
+    return subpartner_config
+
+
+def fix_partner_config(orig_config):
+    pc = {}
+    with open(LOCALES_FILE) as fh:
+        all_locales = list(json.load(fh).keys())
+    # l10n-changesets.json doesn't include en-US, but the repack list does
+    if "en-US" not in all_locales:
+        all_locales.append("en-US")
+    for kind, kind_config in orig_config.items():
+        if kind == "release-partner-attribution":
+            pc[kind] = {}
+            if kind_config:
+                pc[kind] = {"defaults": kind_config["defaults"]}
+                for config in kind_config["configs"]:
+                    # Make sure our locale list is a subset of all_locales
+                    pc[kind].setdefault("configs", []).append(
+                        _fix_subpartner_locales(config, all_locales)
+                    )
+        else:
+            for partner, partner_config in kind_config.items():
+                for subpartner, subpartner_config in partner_config.items():
+                    # get rid of empty subpartner configs
+                    if not subpartner_config:
+                        continue
+                    # Make sure our locale list is a subset of all_locales
+                    pc.setdefault(kind, {}).setdefault(partner, {})[
+                        subpartner
+                    ] = _fix_subpartner_locales(subpartner_config, all_locales)
+    return pc
+
+
+# seems likely this exists elsewhere already
+def get_ftp_platform(platform):
+    if platform.startswith("win32"):
+        return "win32"
+    if platform.startswith("win64-aarch64"):
+        return "win64-aarch64"
+    if platform.startswith("win64"):
+        return "win64"
+    if platform.startswith("macosx"):
+        return "mac"
+    if platform.startswith("linux-"):
+        return "linux-i686"
+    if platform.startswith("linux64"):
+        return "linux-x86_64"
+    raise ValueError(f"Unimplemented platform {platform}")
+
+
+# Ugh
+def locales_per_build_platform(build_platform, locales):
+    if build_platform.startswith("mac"):
+        exclude = ["ja"]
+    else:
+        exclude = ["ja-JP-mac"]
+    return [locale for locale in locales if locale not in exclude]
+
+
+def get_partner_url_config(parameters, graph_config):
+    partner_url_config = copy_task(graph_config["partner-urls"])
+    substitutions = {
+        "release-product": parameters["release_product"],
+        "release-level": release_level(parameters["project"]),
+        "release-type": parameters["release_type"],
+    }
+    resolve_keyed_by(
+        partner_url_config,
+        "release-eme-free-repack",
+        "eme-free manifest_url",
+        **substitutions,
+    )
+    resolve_keyed_by(
+        partner_url_config,
+        "release-partner-repack",
+        "partner manifest url",
+        **substitutions,
+    )
+    resolve_keyed_by(
+        partner_url_config,
+        "release-partner-attribution",
+        "partner attribution url",
+        **substitutions,
+    )
+    return partner_url_config
+
+
+def get_repack_ids_by_platform(config, build_platform):
+    partner_config = get_partner_config_by_kind(config, config.kind)
+    combinations = []
+    for partner, subconfigs in partner_config.items():
+        for sub_config_name, sub_config in subconfigs.items():
+            if build_platform not in sub_config.get("platforms", []):
+                continue
+            locales = locales_per_build_platform(
+                build_platform, sub_config.get("locales", [])
+            )
+            for locale in locales:
+                combinations.append(f"{partner}/{sub_config_name}/{locale}")
+    return sorted(combinations)
+
+
+def get_partners_to_be_published(config):
+    # hardcoded kind because release-bouncer-aliases doesn't match otherwise
+    partner_config = get_partner_config_by_kind(config, "release-partner-repack")
+    partners = []
+    for partner, subconfigs in partner_config.items():
+        for sub_config_name, sub_config in subconfigs.items():
+            if sub_config.get("publish_to_releases"):
+                partners.append((partner, sub_config_name, sub_config["platforms"]))
+    return partners
+
+
+def apply_partner_priority(config, jobs):
+    priority = None
+    # Reduce the priority of the partner repack jobs because they don't block QE. Meanwhile
+    # leave EME-free jobs alone because they do, and they'll get the branch priority like the rest
+    # of the release. Only bother with this in production, not on staging releases on try.
+    # medium is the same as mozilla-central, see taskcluster/ci/config.yml. ie higher than
+    # integration branches because we don't want to wait a lot for the graph to be done, but
+    # for multiple releases the partner tasks always wait for non-partner.
+    if (
+        config.kind.startswith(
+            ("release-partner-repack", "release-partner-attribution")
+        )
+        and release_level(config.params["project"]) == "production"
+    ):
+        priority = "medium"
+    for job in jobs:
+        if priority:
+            job["priority"] = priority
+        yield job
+
+
+def generate_attribution_code(defaults, partner):
+    params = {
+        "medium": defaults["medium"],
+        "source": defaults["source"],
+        "campaign": partner["campaign"],
+        "content": partner["content"],
+    }
+    if partner.get("variation"):
+        params["variation"] = partner["variation"]
+    if partner.get("experiment"):
+        params["experiment"] = partner["experiment"]
+
+    code = urlencode(params)
+    return code
diff --git a/taskcluster/gecko_taskgraph/util/perfile.py b/taskcluster/gecko_taskgraph/util/perfile.py
new file mode 100644
index 0000000000..4e82d87dad
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/perfile.py
@@ -0,0 +1,104 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import itertools
+import json
+import logging
+import math
+
+import taskgraph
+from mozbuild.util import memoize
+from mozpack.path import match as mozpackmatch
+
+from gecko_taskgraph import files_changed
+
+from .. import GECKO
+
+logger = logging.getLogger(__name__)
+
+
+@memoize
+def perfile_number_of_chunks(is_try, try_task_config, head_repository, head_rev, type):
+    if taskgraph.fast and not is_try:
+        # When iterating on taskgraph changes, the exact number of chunks that
+        # test-verify runs usually isn't important, so skip it when going fast.
+        return 3
+    tests_per_chunk = 10.0
+    if type.startswith("test-coverage"):
+        tests_per_chunk = 30.0
+
+    if type.startswith("test-verify-wpt") or type.startswith("test-coverage-wpt"):
+        file_patterns = [
+            "testing/web-platform/tests/**",
+            "testing/web-platform/mozilla/tests/**",
+        ]
+    elif type.startswith("test-verify-gpu") or type.startswith("test-coverage-gpu"):
+        file_patterns = [
+            "**/*webgl*/**/test_*",
+            "**/dom/canvas/**/test_*",
+            "**/gfx/tests/**/test_*",
+            "**/devtools/canvasdebugger/**/browser_*",
+            "**/reftest*/**",
+        ]
+    elif type.startswith("test-verify") or type.startswith("test-coverage"):
+        file_patterns = [
+            "**/test_*",
+            "**/browser_*",
+            "**/crashtest*/**",
+            "js/src/tests/test/**",
+            "js/src/tests/non262/**",
+            "js/src/tests/test262/**",
+        ]
+    else:
+        # Returning 0 means no tests to run, this captures non test-verify tasks
+        return 1
+
+    changed_files = set()
+    if try_task_config:
+        suite_to_paths = json.loads(try_task_config)
+        specified_files = itertools.chain.from_iterable(suite_to_paths.values())
+        changed_files.update(specified_files)
+
+    if is_try:
+        changed_files.update(files_changed.get_locally_changed_files(GECKO))
+    else:
+        changed_files.update(files_changed.get_changed_files(head_repository, head_rev))
+
+    test_count = 0
+    for pattern in file_patterns:
+        for path in changed_files:
+            # TODO: consider running tests if a manifest changes
+            if path.endswith(".list") or path.endswith(".ini"):
+                continue
+            if path.endswith("^headers^"):
+                continue
+
+            if mozpackmatch(path, pattern):
+                gpu = False
+                if type == "test-verify-e10s" or type == "test-coverage-e10s":
+                    # file_patterns for test-verify will pick up some gpu tests, lets ignore
+                    # in the case of reftest, we will not have any in the regular case
+                    gpu_dirs = [
+                        "dom/canvas",
+                        "gfx/tests",
+                        "devtools/canvasdebugger",
+                        "webgl",
+                    ]
+                    for gdir in gpu_dirs:
+                        if len(path.split(gdir)) > 1:
+                            gpu = True
+
+                if not gpu:
+                    test_count += 1
+
+    chunks = test_count / tests_per_chunk
+    chunks = int(math.ceil(chunks))
+
+    # Never return 0 chunks on try, so that per-file tests can be pushed to try with
+    # an explicit path, and also so "empty" runs can be checked on try.
+    if is_try and chunks == 0:
+        chunks = 1
+
+    return chunks
diff --git a/taskcluster/gecko_taskgraph/util/platforms.py b/taskcluster/gecko_taskgraph/util/platforms.py
new file mode 100644
index 0000000000..2c423223fe
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/platforms.py
@@ -0,0 +1,58 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import re
+
+from taskgraph.util.attributes import keymatch
+
+# platform family is extracted from build platform by taking the alphabetic prefix
+# and then translating win -> windows
+_platform_re = re.compile(r"^[a-z]*")
+_renames = {"win": "windows"}
+
+
+_archive_formats = {
+    "linux": ".tar.bz2",
+    "macosx": ".tar.gz",
+    "windows": ".zip",
+}
+
+_executable_extension = {
+    "linux": "",
+    "macosx": "",
+    "windows": ".exe",
+}
+
+_architectures = {
+    r"linux\b.*": "x86",
+    r"linux64\b.*": "x86_64",
+    r"macosx64\b.*": "macos-x86_64-aarch64",
+    r"win32\b.*": "x86",
+    r"win64\b(?!-aarch64).*": "x86_64",
+    r"win64-aarch64\b.*": "aarch64",
+}
+
+
+def platform_family(build_platform):
+    """Given a build platform, return the platform family (linux, macosx, etc.)"""
+    family = _platform_re.match(build_platform).group(0)
+    return _renames.get(family, family)
+
+
+def archive_format(build_platform):
+    """Given a build platform, return the archive format used on the platform."""
+    return _archive_formats[platform_family(build_platform)]
+
+
+def executable_extension(build_platform):
+    """Given a build platform, return the executable extension used on the platform."""
+    return _executable_extension[platform_family(build_platform)]
+
+
+def architecture(build_platform):
+    matches = keymatch(_architectures, build_platform)
+    if len(matches) == 1:
+        return matches[0]
+    raise Exception(f"Could not determine architecture of platform `{build_platform}`.")
diff --git a/taskcluster/gecko_taskgraph/util/scriptworker.py b/taskcluster/gecko_taskgraph/util/scriptworker.py
new file mode 100644
index 0000000000..3f1f64d9f8
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/scriptworker.py
@@ -0,0 +1,859 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""Make scriptworker.cot.verify more user friendly by making scopes dynamic.
+
+Scriptworker uses certain scopes to determine which sets of credentials to use.
+Certain scopes are restricted by branch in chain of trust verification, and are
+checked again at the script level.  This file provides functions to adjust
+these scopes automatically by project; this makes pushing to try, forking a
+project branch, and merge day uplifts more user friendly.
+
+In the future, we may adjust scopes by other settings as well, e.g. different
+scopes for `push-to-candidates` rather than `push-to-releases`, even if both
+happen on mozilla-beta and mozilla-release.
+
+Additional configuration is found in the :ref:`graph config <taskgraph-graph-config>`.
+"""
+import functools
+import itertools
+import json
+import os
+from datetime import datetime
+
+import jsone
+from mozbuild.util import memoize
+from taskgraph.util.schema import resolve_keyed_by
+from taskgraph.util.taskcluster import get_artifact_prefix
+from taskgraph.util.yaml import load_yaml
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+# constants {{{1
+"""Map signing scope aliases to sets of projects.
+
+Currently m-c and DevEdition on m-b use nightly signing; Beta on m-b and m-r
+use release signing. These data structures aren't set-up to handle different
+scopes on the same repo, so we use a different set of them for DevEdition, and
+callers are responsible for using the correct one (by calling the appropriate
+helper below). More context on this in https://bugzilla.mozilla.org/show_bug.cgi?id=1358601.
+
+We will need to add esr support at some point. Eventually we want to add
+nuance so certain m-b and m-r tasks use dep or nightly signing, and we only
+release sign when we have a signed-off set of candidate builds.  This current
+approach works for now, though.
+
+This is a list of list-pairs, for ordering.
+"""
+SIGNING_SCOPE_ALIAS_TO_PROJECT = [
+    [
+        "all-nightly-branches",
+        {
+            "mozilla-central",
+            "comm-central",
+        },
+    ],
+    [
+        "all-release-branches",
+        {
+            "mozilla-beta",
+            "mozilla-release",
+            "mozilla-esr102",
+            "mozilla-esr115",
+            "comm-beta",
+            "comm-esr102",
+            "comm-esr115",
+        },
+    ],
+]
+
+"""Map the signing scope aliases to the actual scopes.
+"""
+SIGNING_CERT_SCOPES = {
+    "all-release-branches": "signing:cert:release-signing",
+    "all-nightly-branches": "signing:cert:nightly-signing",
+    "default": "signing:cert:dep-signing",
+}
+
+DEVEDITION_SIGNING_SCOPE_ALIAS_TO_PROJECT = [
+    [
+        "beta",
+        {
+            "mozilla-beta",
+        },
+    ]
+]
+
+DEVEDITION_SIGNING_CERT_SCOPES = {
+    "beta": "signing:cert:nightly-signing",
+    "default": "signing:cert:dep-signing",
+}
+
+"""Map beetmover scope aliases to sets of projects.
+"""
+BEETMOVER_SCOPE_ALIAS_TO_PROJECT = [
+    [
+        "all-nightly-branches",
+        {
+            "mozilla-central",
+            "comm-central",
+            "oak",
+        },
+    ],
+    [
+        "all-release-branches",
+        {
+            "mozilla-beta",
+            "mozilla-release",
+            "mozilla-esr102",
+            "mozilla-esr115",
+            "comm-beta",
+            "comm-esr102",
+            "comm-esr115",
+        },
+    ],
+]
+
+"""Map the beetmover scope aliases to the actual scopes.
+"""
+BEETMOVER_BUCKET_SCOPES = {
+    "all-release-branches": "beetmover:bucket:release",
+    "all-nightly-branches": "beetmover:bucket:nightly",
+    "default": "beetmover:bucket:dep",
+}
+
+"""Map the beetmover scope aliases to the actual scopes.
+These are the scopes needed to import artifacts into the product delivery APT repos.
+"""
+BEETMOVER_APT_REPO_SCOPES = {
+    "all-release-branches": "beetmover:apt-repo:release",
+    "all-nightly-branches": "beetmover:apt-repo:nightly",
+    "default": "beetmover:apt-repo:dep",
+}
+
+"""Map the beetmover tasks aliases to the actual action scopes.
+"""
+BEETMOVER_ACTION_SCOPES = {
+    "nightly": "beetmover:action:push-to-nightly",
+    "nightly-oak": "beetmover:action:push-to-nightly",
+    "default": "beetmover:action:push-to-candidates",
+}
+
+"""Map the beetmover tasks aliases to the actual action scopes.
+The action scopes are generic across different repo types.
+"""
+BEETMOVER_REPO_ACTION_SCOPES = {
+    "default": "beetmover:action:import-from-gcs-to-artifact-registry",
+}
+
+"""Known balrog actions."""
+BALROG_ACTIONS = (
+    "submit-locale",
+    "submit-toplevel",
+    "schedule",
+    "v2-submit-locale",
+    "v2-submit-toplevel",
+)
+
+"""Map balrog scope aliases to sets of projects.
+
+This is a list of list-pairs, for ordering.
+"""
+BALROG_SCOPE_ALIAS_TO_PROJECT = [
+    [
+        "nightly",
+        {
+            "mozilla-central",
+            "comm-central",
+            "oak",
+        },
+    ],
+    [
+        "beta",
+        {
+            "mozilla-beta",
+            "comm-beta",
+        },
+    ],
+    [
+        "release",
+        {
+            "mozilla-release",
+            "comm-esr102",
+            "comm-esr115",
+        },
+    ],
+    [
+        "esr102",
+        {
+            "mozilla-esr102",
+        },
+    ],
+    [
+        "esr115",
+        {
+            "mozilla-esr115",
+        },
+    ],
+]
+
+"""Map the balrog scope aliases to the actual scopes.
+"""
+BALROG_SERVER_SCOPES = {
+    "nightly": "balrog:server:nightly",
+    "aurora": "balrog:server:aurora",
+    "beta": "balrog:server:beta",
+    "release": "balrog:server:release",
+    "esr102": "balrog:server:esr",
+    "esr115": "balrog:server:esr",
+    "default": "balrog:server:dep",
+}
+
+
+""" The list of the release promotion phases which we send notifications for
+"""
+RELEASE_NOTIFICATION_PHASES = ("promote", "push", "ship")
+
+
+def add_scope_prefix(config, scope):
+    """
+    Prepends the scriptworker scope prefix from the :ref:`graph config
+    <taskgraph-graph-config>`.
+
+    Args:
+        config (TransformConfig): The configuration for the kind being transformed.
+        scope (string): The suffix of the scope
+
+    Returns:
+        string: the scope to use.
+    """
+    return "{prefix}:{scope}".format(
+        prefix=config.graph_config["scriptworker"]["scope-prefix"],
+        scope=scope,
+    )
+
+
+def with_scope_prefix(f):
+    """
+    Wraps a function, calling :py:func:`add_scope_prefix` on the result of
+    calling the wrapped function.
+
+    Args:
+        f (callable): A function that takes a ``config`` and some keyword
+            arguments, and returns a scope suffix.
+
+    Returns:
+        callable: the wrapped function
+    """
+
+    @functools.wraps(f)
+    def wrapper(config, **kwargs):
+        scope_or_scopes = f(config, **kwargs)
+        if isinstance(scope_or_scopes, list):
+            return map(functools.partial(add_scope_prefix, config), scope_or_scopes)
+        return add_scope_prefix(config, scope_or_scopes)
+
+    return wrapper
+
+
+# scope functions {{{1
+@with_scope_prefix
+def get_scope_from_project(config, alias_to_project_map, alias_to_scope_map):
+    """Determine the restricted scope from `config.params['project']`.
+
+    Args:
+        config (TransformConfig): The configuration for the kind being transformed.
+        alias_to_project_map (list of lists): each list pair contains the
+            alias and the set of projects that match.  This is ordered.
+        alias_to_scope_map (dict): the alias alias to scope
+
+    Returns:
+        string: the scope to use.
+    """
+    for alias, projects in alias_to_project_map:
+        if config.params["project"] in projects and alias in alias_to_scope_map:
+            return alias_to_scope_map[alias]
+    return alias_to_scope_map["default"]
+
+
+@with_scope_prefix
+def get_scope_from_release_type(config, release_type_to_scope_map):
+    """Determine the restricted scope from `config.params['target_tasks_method']`.
+
+    Args:
+        config (TransformConfig): The configuration for the kind being transformed.
+        release_type_to_scope_map (dict): the maps release types to scopes
+
+    Returns:
+        string: the scope to use.
+    """
+    return release_type_to_scope_map.get(
+        config.params["release_type"], release_type_to_scope_map["default"]
+    )
+
+
+def get_phase_from_target_method(config, alias_to_tasks_map, alias_to_phase_map):
+    """Determine the phase from `config.params['target_tasks_method']`.
+
+    Args:
+        config (TransformConfig): The configuration for the kind being transformed.
+        alias_to_tasks_map (list of lists): each list pair contains the
+            alias and the set of target methods that match. This is ordered.
+        alias_to_phase_map (dict): the alias to phase map
+
+    Returns:
+        string: the phase to use.
+    """
+    for alias, tasks in alias_to_tasks_map:
+        if (
+            config.params["target_tasks_method"] in tasks
+            and alias in alias_to_phase_map
+        ):
+            return alias_to_phase_map[alias]
+    return alias_to_phase_map["default"]
+
+
+get_signing_cert_scope = functools.partial(
+    get_scope_from_project,
+    alias_to_project_map=SIGNING_SCOPE_ALIAS_TO_PROJECT,
+    alias_to_scope_map=SIGNING_CERT_SCOPES,
+)
+
+get_devedition_signing_cert_scope = functools.partial(
+    get_scope_from_project,
+    alias_to_project_map=DEVEDITION_SIGNING_SCOPE_ALIAS_TO_PROJECT,
+    alias_to_scope_map=DEVEDITION_SIGNING_CERT_SCOPES,
+)
+
+get_beetmover_bucket_scope = functools.partial(
+    get_scope_from_project,
+    alias_to_project_map=BEETMOVER_SCOPE_ALIAS_TO_PROJECT,
+    alias_to_scope_map=BEETMOVER_BUCKET_SCOPES,
+)
+
+get_beetmover_apt_repo_scope = functools.partial(
+    get_scope_from_project,
+    alias_to_project_map=BEETMOVER_SCOPE_ALIAS_TO_PROJECT,
+    alias_to_scope_map=BEETMOVER_APT_REPO_SCOPES,
+)
+
+get_beetmover_repo_action_scope = functools.partial(
+    get_scope_from_release_type,
+    release_type_to_scope_map=BEETMOVER_REPO_ACTION_SCOPES,
+)
+
+get_beetmover_action_scope = functools.partial(
+    get_scope_from_release_type,
+    release_type_to_scope_map=BEETMOVER_ACTION_SCOPES,
+)
+
+get_balrog_server_scope = functools.partial(
+    get_scope_from_project,
+    alias_to_project_map=BALROG_SCOPE_ALIAS_TO_PROJECT,
+    alias_to_scope_map=BALROG_SERVER_SCOPES,
+)
+
+cached_load_yaml = memoize(load_yaml)
+
+
+# release_config {{{1
+def get_release_config(config):
+    """Get the build number and version for a release task.
+
+    Currently only applies to beetmover tasks.
+
+    Args:
+        config (TransformConfig): The configuration for the kind being transformed.
+
+    Returns:
+        dict: containing both `build_number` and `version`.  This can be used to
+            update `task.payload`.
+    """
+    release_config = {}
+
+    partial_updates = os.environ.get("PARTIAL_UPDATES", "")
+    if partial_updates != "" and config.kind in (
+        "release-bouncer-sub",
+        "release-bouncer-check",
+        "release-update-verify-config",
+        "release-secondary-update-verify-config",
+        "release-balrog-submit-toplevel",
+        "release-secondary-balrog-submit-toplevel",
+    ):
+        partial_updates = json.loads(partial_updates)
+        release_config["partial_versions"] = ", ".join(
+            [
+                "{}build{}".format(v, info["buildNumber"])
+                for v, info in partial_updates.items()
+            ]
+        )
+        if release_config["partial_versions"] == "{}":
+            del release_config["partial_versions"]
+
+    release_config["version"] = config.params["version"]
+    release_config["appVersion"] = config.params["app_version"]
+
+    release_config["next_version"] = config.params["next_version"]
+    release_config["build_number"] = config.params["build_number"]
+    return release_config
+
+
+def get_signing_cert_scope_per_platform(build_platform, is_shippable, config):
+    if "devedition" in build_platform:
+        return get_devedition_signing_cert_scope(config)
+    if is_shippable:
+        return get_signing_cert_scope(config)
+    return add_scope_prefix(config, "signing:cert:dep-signing")
+
+
+# generate_beetmover_upstream_artifacts {{{1
+def generate_beetmover_upstream_artifacts(
+    config, job, platform, locale=None, dependencies=None, **kwargs
+):
+    """Generate the upstream artifacts for beetmover, using the artifact map.
+
+    Currently only applies to beetmover tasks.
+
+    Args:
+        job (dict): The current job being generated
+        dependencies (list): A list of the job's dependency labels.
+        platform (str): The current build platform
+        locale (str): The current locale being beetmoved.
+
+    Returns:
+        list: A list of dictionaries conforming to the upstream_artifacts spec.
+    """
+    base_artifact_prefix = get_artifact_prefix(job)
+    resolve_keyed_by(
+        job,
+        "attributes.artifact_map",
+        "artifact map",
+        **{
+            "release-type": config.params["release_type"],
+            "platform": platform,
+        },
+    )
+    map_config = copy_task(cached_load_yaml(job["attributes"]["artifact_map"]))
+    upstream_artifacts = list()
+
+    if not locale:
+        locales = map_config["default_locales"]
+    elif isinstance(locale, list):
+        locales = locale
+    else:
+        locales = [locale]
+
+    if not dependencies:
+        if job.get("dependencies"):
+            dependencies = job["dependencies"].keys()
+        elif job.get("primary-dependency"):
+            dependencies = [job["primary-dependency"].kind]
+        else:
+            raise Exception(f"Unsupported type of dependency. Got job: {job}")
+
+    for locale, dep in itertools.product(locales, dependencies):
+        paths = list()
+
+        for filename in map_config["mapping"]:
+            resolve_keyed_by(
+                map_config["mapping"][filename],
+                "from",
+                f"beetmover filename {filename}",
+                platform=platform,
+            )
+            if dep not in map_config["mapping"][filename]["from"]:
+                continue
+            if locale != "en-US" and not map_config["mapping"][filename]["all_locales"]:
+                continue
+            if (
+                "only_for_platforms" in map_config["mapping"][filename]
+                and platform
+                not in map_config["mapping"][filename]["only_for_platforms"]
+            ):
+                continue
+            if (
+                "not_for_platforms" in map_config["mapping"][filename]
+                and platform in map_config["mapping"][filename]["not_for_platforms"]
+            ):
+                continue
+            if "partials_only" in map_config["mapping"][filename]:
+                continue
+            # The next time we look at this file it might be a different locale.
+            file_config = copy_task(map_config["mapping"][filename])
+            resolve_keyed_by(
+                file_config,
+                "source_path_modifier",
+                "source path modifier",
+                locale=locale,
+            )
+
+            kwargs["locale"] = locale
+
+            paths.append(
+                os.path.join(
+                    base_artifact_prefix,
+                    jsone.render(file_config["source_path_modifier"], kwargs),
+                    jsone.render(filename, kwargs),
+                )
+            )
+
+        if (
+            job.get("dependencies")
+            and getattr(job["dependencies"][dep], "attributes", None)
+            and job["dependencies"][dep].attributes.get("release_artifacts")
+        ):
+            paths = [
+                path
+                for path in paths
+                if path in job["dependencies"][dep].attributes["release_artifacts"]
+            ]
+
+        if not paths:
+            continue
+
+        upstream_artifacts.append(
+            {
+                "taskId": {"task-reference": f"<{dep}>"},
+                "taskType": map_config["tasktype_map"].get(dep),
+                "paths": sorted(paths),
+                "locale": locale,
+            }
+        )
+
+    upstream_artifacts.sort(key=lambda u: u["paths"])
+    return upstream_artifacts
+
+
+def generate_artifact_registry_gcs_sources(dep):
+    gcs_sources = []
+    locale = dep.attributes.get("locale")
+    if not locale:
+        repackage_deb_reference = "<repackage-deb>"
+        repackage_deb_artifact = "public/build/target.deb"
+    else:
+        repackage_deb_reference = "<repackage-deb-l10n>"
+        repackage_deb_artifact = f"public/build/{locale}/target.langpack.deb"
+    for config in dep.task["payload"]["artifactMap"]:
+        if (
+            config["taskId"]["task-reference"] == repackage_deb_reference
+            and repackage_deb_artifact in config["paths"]
+        ):
+            gcs_sources.append(
+                config["paths"][repackage_deb_artifact]["destinations"][0]
+            )
+    return gcs_sources
+
+
+# generate_beetmover_artifact_map {{{1
+def generate_beetmover_artifact_map(config, job, **kwargs):
+    """Generate the beetmover artifact map.
+
+    Currently only applies to beetmover tasks.
+
+    Args:
+        config (): Current taskgraph configuration.
+        job (dict): The current job being generated
+    Common kwargs:
+        platform (str): The current build platform
+        locale (str): The current locale being beetmoved.
+
+    Returns:
+        list: A list of dictionaries containing source->destination
+            maps for beetmover.
+    """
+    platform = kwargs.get("platform", "")
+    resolve_keyed_by(
+        job,
+        "attributes.artifact_map",
+        job["label"],
+        **{
+            "release-type": config.params["release_type"],
+            "platform": platform,
+        },
+    )
+    map_config = copy_task(cached_load_yaml(job["attributes"]["artifact_map"]))
+    base_artifact_prefix = map_config.get(
+        "base_artifact_prefix", get_artifact_prefix(job)
+    )
+
+    artifacts = list()
+
+    dependencies = job["dependencies"].keys()
+
+    if kwargs.get("locale"):
+        if isinstance(kwargs["locale"], list):
+            locales = kwargs["locale"]
+        else:
+            locales = [kwargs["locale"]]
+    else:
+        locales = map_config["default_locales"]
+
+    resolve_keyed_by(map_config, "s3_bucket_paths", job["label"], platform=platform)
+
+    for locale, dep in sorted(itertools.product(locales, dependencies)):
+        paths = dict()
+        for filename in map_config["mapping"]:
+            # Relevancy checks
+            resolve_keyed_by(
+                map_config["mapping"][filename], "from", "blah", platform=platform
+            )
+            if dep not in map_config["mapping"][filename]["from"]:
+                # We don't get this file from this dependency.
+                continue
+            if locale != "en-US" and not map_config["mapping"][filename]["all_locales"]:
+                # This locale either doesn't produce or shouldn't upload this file.
+                continue
+            if (
+                "only_for_platforms" in map_config["mapping"][filename]
+                and platform
+                not in map_config["mapping"][filename]["only_for_platforms"]
+            ):
+                # This platform either doesn't produce or shouldn't upload this file.
+                continue
+            if (
+                "not_for_platforms" in map_config["mapping"][filename]
+                and platform in map_config["mapping"][filename]["not_for_platforms"]
+            ):
+                # This platform either doesn't produce or shouldn't upload this file.
+                continue
+            if "partials_only" in map_config["mapping"][filename]:
+                continue
+
+            # copy_task because the next time we look at this file the locale will differ.
+            file_config = copy_task(map_config["mapping"][filename])
+
+            for field in [
+                "destinations",
+                "locale_prefix",
+                "source_path_modifier",
+                "update_balrog_manifest",
+                "pretty_name",
+                "checksums_path",
+            ]:
+                resolve_keyed_by(
+                    file_config, field, job["label"], locale=locale, platform=platform
+                )
+
+            # This format string should ideally be in the configuration file,
+            # but this would mean keeping variable names in sync between code + config.
+            destinations = [
+                "{s3_bucket_path}/{dest_path}/{locale_prefix}{filename}".format(
+                    s3_bucket_path=bucket_path,
+                    dest_path=dest_path,
+                    locale_prefix=file_config["locale_prefix"],
+                    filename=file_config.get("pretty_name", filename),
+                )
+                for dest_path, bucket_path in itertools.product(
+                    file_config["destinations"], map_config["s3_bucket_paths"]
+                )
+            ]
+            # Creating map entries
+            # Key must be artifact path, to avoid trampling duplicates, such
+            # as public/build/target.apk and public/build/en-US/target.apk
+            key = os.path.join(
+                base_artifact_prefix,
+                file_config["source_path_modifier"],
+                filename,
+            )
+
+            paths[key] = {
+                "destinations": destinations,
+            }
+            if file_config.get("checksums_path"):
+                paths[key]["checksums_path"] = file_config["checksums_path"]
+
+            # optional flag: balrog manifest
+            if file_config.get("update_balrog_manifest"):
+                paths[key]["update_balrog_manifest"] = True
+                if file_config.get("balrog_format"):
+                    paths[key]["balrog_format"] = file_config["balrog_format"]
+
+        if not paths:
+            # No files for this dependency/locale combination.
+            continue
+
+        # Render all variables for the artifact map
+        platforms = copy_task(map_config.get("platform_names", {}))
+        if platform:
+            for key in platforms.keys():
+                resolve_keyed_by(platforms, key, job["label"], platform=platform)
+
+        upload_date = datetime.fromtimestamp(config.params["build_date"])
+
+        kwargs.update(
+            {
+                "locale": locale,
+                "version": config.params["version"],
+                "branch": config.params["project"],
+                "build_number": config.params["build_number"],
+                "year": upload_date.year,
+                "month": upload_date.strftime("%m"),  # zero-pad the month
+                "upload_date": upload_date.strftime("%Y-%m-%d-%H-%M-%S"),
+            }
+        )
+        kwargs.update(**platforms)
+        paths = jsone.render(paths, kwargs)
+        artifacts.append(
+            {
+                "taskId": {"task-reference": f"<{dep}>"},
+                "locale": locale,
+                "paths": paths,
+            }
+        )
+
+    return artifacts
+
+
+# generate_beetmover_partials_artifact_map {{{1
+def generate_beetmover_partials_artifact_map(config, job, partials_info, **kwargs):
+    """Generate the beetmover partials artifact map.
+
+    Currently only applies to beetmover tasks.
+
+    Args:
+        config (): Current taskgraph configuration.
+        job (dict): The current job being generated
+        partials_info (dict): Current partials and information about them in a dict
+    Common kwargs:
+        platform (str): The current build platform
+        locale (str): The current locale being beetmoved.
+
+    Returns:
+        list: A list of dictionaries containing source->destination
+            maps for beetmover.
+    """
+    platform = kwargs.get("platform", "")
+    resolve_keyed_by(
+        job,
+        "attributes.artifact_map",
+        "artifact map",
+        **{
+            "release-type": config.params["release_type"],
+            "platform": platform,
+        },
+    )
+    map_config = copy_task(cached_load_yaml(job["attributes"]["artifact_map"]))
+    base_artifact_prefix = map_config.get(
+        "base_artifact_prefix", get_artifact_prefix(job)
+    )
+
+    artifacts = list()
+    dependencies = job["dependencies"].keys()
+
+    if kwargs.get("locale"):
+        locales = [kwargs["locale"]]
+    else:
+        locales = map_config["default_locales"]
+
+    resolve_keyed_by(
+        map_config, "s3_bucket_paths", "s3_bucket_paths", platform=platform
+    )
+
+    platforms = copy_task(map_config.get("platform_names", {}))
+    if platform:
+        for key in platforms.keys():
+            resolve_keyed_by(platforms, key, key, platform=platform)
+    upload_date = datetime.fromtimestamp(config.params["build_date"])
+
+    for locale, dep in itertools.product(locales, dependencies):
+        paths = dict()
+        for filename in map_config["mapping"]:
+            # Relevancy checks
+            if dep not in map_config["mapping"][filename]["from"]:
+                # We don't get this file from this dependency.
+                continue
+            if locale != "en-US" and not map_config["mapping"][filename]["all_locales"]:
+                # This locale either doesn't produce or shouldn't upload this file.
+                continue
+            if "partials_only" not in map_config["mapping"][filename]:
+                continue
+            # copy_task because the next time we look at this file the locale will differ.
+            file_config = copy_task(map_config["mapping"][filename])
+
+            for field in [
+                "destinations",
+                "locale_prefix",
+                "source_path_modifier",
+                "update_balrog_manifest",
+                "from_buildid",
+                "pretty_name",
+                "checksums_path",
+            ]:
+                resolve_keyed_by(
+                    file_config, field, field, locale=locale, platform=platform
+                )
+
+            # This format string should ideally be in the configuration file,
+            # but this would mean keeping variable names in sync between code + config.
+            destinations = [
+                "{s3_bucket_path}/{dest_path}/{locale_prefix}{filename}".format(
+                    s3_bucket_path=bucket_path,
+                    dest_path=dest_path,
+                    locale_prefix=file_config["locale_prefix"],
+                    filename=file_config.get("pretty_name", filename),
+                )
+                for dest_path, bucket_path in itertools.product(
+                    file_config["destinations"], map_config["s3_bucket_paths"]
+                )
+            ]
+            # Creating map entries
+            # Key must be artifact path, to avoid trampling duplicates, such
+            # as public/build/target.apk and public/build/en-US/target.apk
+            key = os.path.join(
+                base_artifact_prefix,
+                file_config["source_path_modifier"],
+                filename,
+            )
+            partials_paths = {}
+            for pname, info in partials_info.items():
+                partials_paths[key] = {
+                    "destinations": destinations,
+                }
+                if file_config.get("checksums_path"):
+                    partials_paths[key]["checksums_path"] = file_config[
+                        "checksums_path"
+                    ]
+
+                # optional flag: balrog manifest
+                if file_config.get("update_balrog_manifest"):
+                    partials_paths[key]["update_balrog_manifest"] = True
+                    if file_config.get("balrog_format"):
+                        partials_paths[key]["balrog_format"] = file_config[
+                            "balrog_format"
+                        ]
+                # optional flag: from_buildid
+                if file_config.get("from_buildid"):
+                    partials_paths[key]["from_buildid"] = file_config["from_buildid"]
+
+                # render buildid
+                kwargs.update(
+                    {
+                        "partial": pname,
+                        "from_buildid": info["buildid"],
+                        "previous_version": info.get("previousVersion"),
+                        "buildid": str(config.params["moz_build_date"]),
+                        "locale": locale,
+                        "version": config.params["version"],
+                        "branch": config.params["project"],
+                        "build_number": config.params["build_number"],
+                        "year": upload_date.year,
+                        "month": upload_date.strftime("%m"),  # zero-pad the month
+                        "upload_date": upload_date.strftime("%Y-%m-%d-%H-%M-%S"),
+                    }
+                )
+                kwargs.update(**platforms)
+                paths.update(jsone.render(partials_paths, kwargs))
+
+        if not paths:
+            continue
+
+        artifacts.append(
+            {
+                "taskId": {"task-reference": f"<{dep}>"},
+                "locale": locale,
+                "paths": paths,
+            }
+        )
+
+    artifacts.sort(key=lambda a: sorted(a["paths"].items()))
+    return artifacts
diff --git a/taskcluster/gecko_taskgraph/util/signed_artifacts.py b/taskcluster/gecko_taskgraph/util/signed_artifacts.py
new file mode 100644
index 0000000000..2467ff8046
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/signed_artifacts.py
@@ -0,0 +1,198 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+Defines artifacts to sign before repackage.
+"""
+
+from taskgraph.util.taskcluster import get_artifact_path
+
+from gecko_taskgraph.util.declarative_artifacts import get_geckoview_upstream_artifacts
+
+LANGPACK_SIGN_PLATFORMS = {  # set
+    "linux64-shippable",
+    "linux64-devedition",
+    "macosx64-shippable",
+    "macosx64-devedition",
+}
+
+
+def is_partner_kind(kind):
+    if kind and kind.startswith(("release-partner", "release-eme-free")):
+        return True
+
+
+def is_notarization_kind(kind):
+    if kind and "notarization" in kind:
+        return True
+
+
+def is_mac_signing_king(kind):
+    return kind and "mac-signing" in kind
+
+
+def generate_specifications_of_artifacts_to_sign(
+    config, job, keep_locale_template=True, kind=None, dep_kind=None
+):
+    build_platform = job["attributes"].get("build_platform")
+    use_stub = job["attributes"].get("stub-installer")
+    # Get locales to know if we want to sign ja-JP-mac langpack
+    locales = job["attributes"].get("chunk_locales", [])
+    if kind == "release-source-signing":
+        artifacts_specifications = [
+            {
+                "artifacts": [get_artifact_path(job, "source.tar.xz")],
+                "formats": ["autograph_gpg"],
+            }
+        ]
+    elif "android" in build_platform:
+        artifacts_specifications = [
+            {
+                "artifacts": get_geckoview_artifacts_to_sign(config, job),
+                "formats": ["autograph_gpg"],
+            }
+        ]
+    # XXX: Mars aren't signed here (on any platform) because internals will be
+    # signed at after this stage of the release
+    elif "macosx" in build_platform:
+        langpack_formats = []
+        if is_notarization_kind(config.kind):
+            formats = ["apple_notarization"]
+            artifacts_specifications = [
+                {
+                    "artifacts": [
+                        get_artifact_path(job, "{locale}/target.tar.gz"),
+                        get_artifact_path(job, "{locale}/target.pkg"),
+                    ],
+                    "formats": formats,
+                }
+            ]
+        else:
+            # This task is mac-signing
+            if is_partner_kind(kind):
+                extension = "tar.gz"
+            else:
+                extension = "dmg"
+            artifacts_specifications = [
+                {
+                    "artifacts": [
+                        get_artifact_path(job, f"{{locale}}/target.{extension}")
+                    ],
+                    "formats": ["macapp", "autograph_widevine", "autograph_omnija"],
+                }
+            ]
+            langpack_formats = ["autograph_langpack"]
+
+        if "ja-JP-mac" in locales and build_platform in LANGPACK_SIGN_PLATFORMS:
+            artifacts_specifications += [
+                {
+                    "artifacts": [
+                        get_artifact_path(job, "ja-JP-mac/target.langpack.xpi")
+                    ],
+                    "formats": langpack_formats,
+                }
+            ]
+    elif "win" in build_platform:
+        artifacts_specifications = [
+            {
+                "artifacts": [
+                    get_artifact_path(job, "{locale}/setup.exe"),
+                ],
+                "formats": ["autograph_authenticode_sha2"],
+            },
+            {
+                "artifacts": [
+                    get_artifact_path(job, "{locale}/target.zip"),
+                ],
+                "formats": [
+                    "autograph_authenticode_sha2",
+                    "autograph_widevine",
+                    "autograph_omnija",
+                ],
+            },
+        ]
+
+        if use_stub:
+            artifacts_specifications[0]["artifacts"] += [
+                get_artifact_path(job, "{locale}/setup-stub.exe")
+            ]
+    elif "linux" in build_platform:
+        artifacts_specifications = [
+            {
+                "artifacts": [get_artifact_path(job, "{locale}/target.tar.bz2")],
+                "formats": ["autograph_gpg", "autograph_widevine", "autograph_omnija"],
+            }
+        ]
+        if build_platform in LANGPACK_SIGN_PLATFORMS:
+            artifacts_specifications += [
+                {
+                    "artifacts": [
+                        get_artifact_path(job, "{locale}/target.langpack.xpi")
+                    ],
+                    "formats": ["autograph_langpack"],
+                }
+            ]
+    else:
+        raise Exception("Platform not implemented for signing")
+
+    if not keep_locale_template:
+        artifacts_specifications = _strip_locale_template(artifacts_specifications)
+
+    if is_partner_kind(kind):
+        artifacts_specifications = _strip_widevine_for_partners(
+            artifacts_specifications
+        )
+
+    return artifacts_specifications
+
+
+def _strip_locale_template(artifacts_without_locales):
+    for spec in artifacts_without_locales:
+        for index, artifact in enumerate(spec["artifacts"]):
+            stripped_artifact = artifact.format(locale="")
+            stripped_artifact = stripped_artifact.replace("//", "/")
+            spec["artifacts"][index] = stripped_artifact
+
+    return artifacts_without_locales
+
+
+def _strip_widevine_for_partners(artifacts_specifications):
+    """Partner repacks should not resign that's previously signed for fear of breaking partial
+    updates
+    """
+    for spec in artifacts_specifications:
+        if "autograph_widevine" in spec["formats"]:
+            spec["formats"].remove("autograph_widevine")
+        if "autograph_omnija" in spec["formats"]:
+            spec["formats"].remove("autograph_omnija")
+
+    return artifacts_specifications
+
+
+def get_signed_artifacts(input, formats, behavior=None):
+    """
+    Get the list of signed artifacts for the given input and formats.
+    """
+    artifacts = set()
+    if input.endswith(".dmg"):
+        artifacts.add(input.replace(".dmg", ".tar.gz"))
+        if behavior and behavior != "mac_sign":
+            artifacts.add(input.replace(".dmg", ".pkg"))
+    else:
+        artifacts.add(input)
+    if "autograph_gpg" in formats:
+        artifacts.add(f"{input}.asc")
+
+    return artifacts
+
+
+def get_geckoview_artifacts_to_sign(config, job):
+    upstream_artifacts = []
+    for package in job["attributes"]["maven_packages"]:
+        upstream_artifacts += get_geckoview_upstream_artifacts(config, job, package)
+    return [
+        path
+        for upstream_artifact in upstream_artifacts
+        for path in upstream_artifact["paths"]
+        if not path.endswith(".md5") and not path.endswith(".sha1")
+    ]
diff --git a/taskcluster/gecko_taskgraph/util/taskcluster.py b/taskcluster/gecko_taskgraph/util/taskcluster.py
new file mode 100644
index 0000000000..cddb01fd37
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/taskcluster.py
@@ -0,0 +1,128 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import os
+
+import taskcluster_urls as liburls
+from taskcluster import Hooks
+from taskgraph.util import taskcluster as tc_util
+from taskgraph.util.taskcluster import (
+    _do_request,
+    get_index_url,
+    get_root_url,
+    get_task_definition,
+    get_task_url,
+)
+
+logger = logging.getLogger(__name__)
+
+
+def insert_index(index_path, task_id, data=None, use_proxy=False):
+    index_url = get_index_url(index_path, use_proxy=use_proxy)
+
+    # Find task expiry.
+    expires = get_task_definition(task_id, use_proxy=use_proxy)["expires"]
+
+    response = _do_request(
+        index_url,
+        method="put",
+        json={
+            "taskId": task_id,
+            "rank": 0,
+            "data": data or {},
+            "expires": expires,
+        },
+    )
+    return response
+
+
+def status_task(task_id, use_proxy=False):
+    """Gets the status of a task given a task_id.
+
+    In testing mode, just logs that it would have retrieved status.
+
+    Args:
+        task_id (str): A task id.
+        use_proxy (bool): Whether to use taskcluster-proxy (default: False)
+
+    Returns:
+        dict: A dictionary object as defined here:
+          https://docs.taskcluster.net/docs/reference/platform/queue/api#status
+    """
+    if tc_util.testing:
+        logger.info(f"Would have gotten status for {task_id}.")
+    else:
+        resp = _do_request(get_task_url(task_id, use_proxy) + "/status")
+        status = resp.json().get("status", {})
+        return status
+
+
+def state_task(task_id, use_proxy=False):
+    """Gets the state of a task given a task_id.
+
+    In testing mode, just logs that it would have retrieved state. This is a subset of the
+    data returned by :func:`status_task`.
+
+    Args:
+        task_id (str): A task id.
+        use_proxy (bool): Whether to use taskcluster-proxy (default: False)
+
+    Returns:
+        str: The state of the task, one of
+          ``pending, running, completed, failed, exception, unknown``.
+    """
+    if tc_util.testing:
+        logger.info(f"Would have gotten state for {task_id}.")
+    else:
+        status = status_task(task_id, use_proxy=use_proxy).get("state") or "unknown"
+        return status
+
+
+def trigger_hook(hook_group_id, hook_id, hook_payload):
+    hooks = Hooks({"rootUrl": get_root_url(True)})
+    response = hooks.triggerHook(hook_group_id, hook_id, hook_payload)
+
+    logger.info(
+        "Task seen here: {}/tasks/{}".format(
+            get_root_url(os.environ.get("TASKCLUSTER_PROXY_URL")),
+            response["status"]["taskId"],
+        )
+    )
+
+
+def list_task_group_tasks(task_group_id):
+    """Generate the tasks in a task group"""
+    params = {}
+    while True:
+        url = liburls.api(
+            get_root_url(False),
+            "queue",
+            "v1",
+            f"task-group/{task_group_id}/list",
+        )
+        resp = _do_request(url, method="get", params=params).json()
+        yield from resp["tasks"]
+        if resp.get("continuationToken"):
+            params = {"continuationToken": resp.get("continuationToken")}
+        else:
+            break
+
+
+def list_task_group_incomplete_task_ids(task_group_id):
+    states = ("running", "pending", "unscheduled")
+    for task in [t["status"] for t in list_task_group_tasks(task_group_id)]:
+        if task["state"] in states:
+            yield task["taskId"]
+
+
+def list_task_group_complete_tasks(task_group_id):
+    tasks = {}
+    for task in list_task_group_tasks(task_group_id):
+        if task.get("status", {}).get("state", "") == "completed":
+            tasks[task.get("task", {}).get("metadata", {}).get("name", "")] = task.get(
+                "status", {}
+            ).get("taskId", "")
+    return tasks
diff --git a/taskcluster/gecko_taskgraph/util/taskgraph.py b/taskcluster/gecko_taskgraph/util/taskgraph.py
new file mode 100644
index 0000000000..bac7b3fbb8
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/taskgraph.py
@@ -0,0 +1,49 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""
+Tools for interacting with existing taskgraphs.
+"""
+
+from taskgraph.util.taskcluster import find_task_id, get_artifact
+
+
+def find_decision_task(parameters, graph_config):
+    """Given the parameters for this action, find the taskId of the decision
+    task"""
+    head_rev_param = "{}head_rev".format(graph_config["project-repo-param-prefix"])
+    return find_task_id(
+        "{}.v2.{}.revision.{}.taskgraph.decision".format(
+            graph_config["trust-domain"],
+            parameters["project"],
+            parameters[head_rev_param],
+        )
+    )
+
+
+def find_existing_tasks(previous_graph_ids):
+    existing_tasks = {}
+    for previous_graph_id in previous_graph_ids:
+        label_to_taskid = get_artifact(previous_graph_id, "public/label-to-taskid.json")
+        existing_tasks.update(label_to_taskid)
+    return existing_tasks
+
+
+def find_existing_tasks_from_previous_kinds(
+    full_task_graph, previous_graph_ids, rebuild_kinds
+):
+    """Given a list of previous decision/action taskIds and kinds to ignore
+    from the previous graphs, return a dictionary of labels-to-taskids to use
+    as ``existing_tasks`` in the optimization step."""
+    existing_tasks = find_existing_tasks(previous_graph_ids)
+    kind_labels = {
+        t.label
+        for t in full_task_graph.tasks.values()
+        if t.attributes["kind"] not in rebuild_kinds
+    }
+    return {
+        label: taskid
+        for (label, taskid) in existing_tasks.items()
+        if label in kind_labels
+    }
diff --git a/taskcluster/gecko_taskgraph/util/templates.py b/taskcluster/gecko_taskgraph/util/templates.py
new file mode 100644
index 0000000000..e6640a7edd
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/templates.py
@@ -0,0 +1,59 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+from gecko_taskgraph.util.copy_task import copy_task
+
+
+def merge_to(source, dest):
+    """
+    Merge dict and arrays (override scalar values)
+
+    Keys from source override keys from dest, and elements from lists in source
+    are appended to lists in dest.
+
+    :param dict source: to copy from
+    :param dict dest: to copy to (modified in place)
+    """
+
+    for key, value in source.items():
+        if (
+            isinstance(value, dict)
+            and len(value) == 1
+            and list(value)[0].startswith("by-")
+        ):
+            # Do not merge by-* values as this is likely to confuse someone
+            dest[key] = value
+            continue
+
+        # Override mismatching or empty types
+        if type(value) != type(dest.get(key)):  # noqa
+            dest[key] = value
+            continue
+
+        # Merge dict
+        if isinstance(value, dict):
+            merge_to(value, dest[key])
+            continue
+
+        if isinstance(value, list):
+            dest[key] = dest[key] + value
+            continue
+
+        dest[key] = value
+
+    return dest
+
+
+def merge(*objects):
+    """
+    Merge the given objects, using the semantics described for merge_to, with
+    objects later in the list taking precedence.  From an inheritance
+    perspective, "parents" should be listed before "children".
+
+    Returns the result without modifying any arguments.
+    """
+    if len(objects) == 1:
+        return copy_task(objects[0])
+    return merge_to(objects[-1], merge(*objects[:-1]))
diff --git a/taskcluster/gecko_taskgraph/util/verify.py b/taskcluster/gecko_taskgraph/util/verify.py
new file mode 100644
index 0000000000..75ddbda674
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/verify.py
@@ -0,0 +1,454 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import logging
+import os
+import re
+import sys
+
+import attr
+from taskgraph.util.treeherder import join_symbol
+from taskgraph.util.verify import VerificationSequence
+
+from gecko_taskgraph import GECKO
+from gecko_taskgraph.util.attributes import (
+    ALL_PROJECTS,
+    RELEASE_PROJECTS,
+    RUN_ON_PROJECT_ALIASES,
+)
+
+logger = logging.getLogger(__name__)
+doc_base_path = os.path.join(GECKO, "taskcluster", "docs")
+
+
+verifications = VerificationSequence()
+
+
+@attr.s(frozen=True)
+class DocPaths:
+    _paths = attr.ib(factory=list)
+
+    def get_files(self, filename):
+        rv = []
+        for p in self._paths:
+            doc_path = os.path.join(p, filename)
+            if os.path.exists(doc_path):
+                rv.append(doc_path)
+        return rv
+
+    def add(self, path):
+        """
+        Projects that make use of Firefox's taskgraph can extend it with
+        their own task kinds by registering additional paths for documentation.
+        documentation_paths.add() needs to be called by the project's Taskgraph
+        registration function. See taskgraph.config.
+        """
+        self._paths.append(path)
+
+
+documentation_paths = DocPaths()
+documentation_paths.add(doc_base_path)
+
+
+def verify_docs(filename, identifiers, appearing_as):
+    """
+    Look for identifiers of the type appearing_as in the files
+    returned by documentation_paths.get_files(). Firefox will have
+    a single file in a list, but projects such as Thunderbird can have
+    documentation in another location and may return multiple files.
+    """
+    # We ignore identifiers starting with '_' for the sake of tests.
+    # Strings starting with "_" are ignored for doc verification
+    # hence they can be used for faking test values
+    doc_files = documentation_paths.get_files(filename)
+    doctext = "".join([open(d).read() for d in doc_files])
+
+    if appearing_as == "inline-literal":
+        expression_list = [
+            "``" + identifier + "``"
+            for identifier in identifiers
+            if not identifier.startswith("_")
+        ]
+    elif appearing_as == "heading":
+        expression_list = [
+            "\n" + identifier + "\n(?:(?:(?:-+\n)+)|(?:(?:.+\n)+))"
+            for identifier in identifiers
+            if not identifier.startswith("_")
+        ]
+    else:
+        raise Exception(f"appearing_as = `{appearing_as}` not defined")
+
+    for expression, identifier in zip(expression_list, identifiers):
+        match_group = re.search(expression, doctext)
+        if not match_group:
+            raise Exception(
+                "{}: `{}` missing from doc file: `{}`".format(
+                    appearing_as, identifier, filename
+                )
+            )
+
+
+@verifications.add("initial")
+def verify_run_using():
+    from gecko_taskgraph.transforms.job import registry
+
+    verify_docs(
+        filename="transforms/job.rst",
+        identifiers=registry.keys(),
+        appearing_as="inline-literal",
+    )
+
+
+@verifications.add("parameters")
+def verify_parameters_docs(parameters):
+    if not parameters.strict:
+        return
+
+    parameters_dict = dict(**parameters)
+    verify_docs(
+        filename="parameters.rst",
+        identifiers=list(parameters_dict),
+        appearing_as="inline-literal",
+    )
+
+
+@verifications.add("kinds")
+def verify_kinds_docs(kinds):
+    verify_docs(filename="kinds.rst", identifiers=kinds.keys(), appearing_as="heading")
+
+
+@verifications.add("full_task_set")
+def verify_attributes(task, taskgraph, scratch_pad, graph_config, parameters):
+    if task is None:
+        verify_docs(
+            filename="attributes.rst",
+            identifiers=list(scratch_pad["attribute_set"]),
+            appearing_as="heading",
+        )
+        return
+    scratch_pad.setdefault("attribute_set", set()).update(task.attributes.keys())
+
+
+@verifications.add("full_task_graph")
+def verify_task_graph_symbol(task, taskgraph, scratch_pad, graph_config, parameters):
+    """
+    This function verifies that tuple
+    (collection.keys(), machine.platform, groupSymbol, symbol) is unique
+    for a target task graph.
+    """
+    if task is None:
+        return
+    task_dict = task.task
+    if "extra" in task_dict:
+        extra = task_dict["extra"]
+        if "treeherder" in extra:
+            treeherder = extra["treeherder"]
+
+            collection_keys = tuple(sorted(treeherder.get("collection", {}).keys()))
+            if len(collection_keys) != 1:
+                raise Exception(
+                    "Task {} can't be in multiple treeherder collections "
+                    "(the part of the platform after `/`): {}".format(
+                        task.label, collection_keys
+                    )
+                )
+            platform = treeherder.get("machine", {}).get("platform")
+            group_symbol = treeherder.get("groupSymbol")
+            symbol = treeherder.get("symbol")
+
+            key = (platform, collection_keys[0], group_symbol, symbol)
+            if key in scratch_pad:
+                raise Exception(
+                    "Duplicate treeherder platform and symbol in tasks "
+                    "`{}`and `{}`: {} {}".format(
+                        task.label,
+                        scratch_pad[key],
+                        f"{platform}/{collection_keys[0]}",
+                        join_symbol(group_symbol, symbol),
+                    )
+                )
+            else:
+                scratch_pad[key] = task.label
+
+
+@verifications.add("full_task_graph")
+def verify_trust_domain_v2_routes(
+    task, taskgraph, scratch_pad, graph_config, parameters
+):
+    """
+    This function ensures that any two tasks have distinct ``index.{trust-domain}.v2`` routes.
+    """
+    if task is None:
+        return
+    route_prefix = "index.{}.v2".format(graph_config["trust-domain"])
+    task_dict = task.task
+    routes = task_dict.get("routes", [])
+
+    for route in routes:
+        if route.startswith(route_prefix):
+            if route in scratch_pad:
+                raise Exception(
+                    "conflict between {}:{} for route: {}".format(
+                        task.label, scratch_pad[route], route
+                    )
+                )
+            else:
+                scratch_pad[route] = task.label
+
+
+@verifications.add("full_task_graph")
+def verify_routes_notification_filters(
+    task, taskgraph, scratch_pad, graph_config, parameters
+):
+    """
+    This function ensures that only understood filters for notifications are
+    specified.
+
+    See: https://firefox-ci-tc.services.mozilla.com/docs/manual/using/task-notifications
+    """
+    if task is None:
+        return
+    route_prefix = "notify."
+    valid_filters = ("on-any", "on-completed", "on-failed", "on-exception")
+    task_dict = task.task
+    routes = task_dict.get("routes", [])
+
+    for route in routes:
+        if route.startswith(route_prefix):
+            # Get the filter of the route
+            route_filter = route.split(".")[-1]
+            if route_filter not in valid_filters:
+                raise Exception(
+                    "{} has invalid notification filter ({})".format(
+                        task.label, route_filter
+                    )
+                )
+
+
+@verifications.add("full_task_graph")
+def verify_dependency_tiers(task, taskgraph, scratch_pad, graph_config, parameters):
+    tiers = scratch_pad
+    if task is not None:
+        tiers[task.label] = (
+            task.task.get("extra", {}).get("treeherder", {}).get("tier", sys.maxsize)
+        )
+    else:
+
+        def printable_tier(tier):
+            if tier == sys.maxsize:
+                return "unknown"
+            return tier
+
+        for task in taskgraph.tasks.values():
+            tier = tiers[task.label]
+            for d in task.dependencies.values():
+                if taskgraph[d].task.get("workerType") == "always-optimized":
+                    continue
+                if "dummy" in taskgraph[d].kind:
+                    continue
+                if tier < tiers[d]:
+                    raise Exception(
+                        "{} (tier {}) cannot depend on {} (tier {})".format(
+                            task.label,
+                            printable_tier(tier),
+                            d,
+                            printable_tier(tiers[d]),
+                        )
+                    )
+
+
+@verifications.add("full_task_graph")
+def verify_required_signoffs(task, taskgraph, scratch_pad, graph_config, parameters):
+    """
+    Task with required signoffs can't be dependencies of tasks with less
+    required signoffs.
+    """
+    all_required_signoffs = scratch_pad
+    if task is not None:
+        all_required_signoffs[task.label] = set(
+            task.attributes.get("required_signoffs", [])
+        )
+    else:
+
+        def printable_signoff(signoffs):
+            if len(signoffs) == 1:
+                return "required signoff {}".format(*signoffs)
+            if signoffs:
+                return "required signoffs {}".format(", ".join(signoffs))
+            return "no required signoffs"
+
+        for task in taskgraph.tasks.values():
+            required_signoffs = all_required_signoffs[task.label]
+            for d in task.dependencies.values():
+                if required_signoffs < all_required_signoffs[d]:
+                    raise Exception(
+                        "{} ({}) cannot depend on {} ({})".format(
+                            task.label,
+                            printable_signoff(required_signoffs),
+                            d,
+                            printable_signoff(all_required_signoffs[d]),
+                        )
+                    )
+
+
+@verifications.add("full_task_graph")
+def verify_aliases(task, taskgraph, scratch_pad, graph_config, parameters):
+    """
+    This function verifies that aliases are not reused.
+    """
+    if task is None:
+        return
+    if task.kind not in ("toolchain", "fetch"):
+        return
+    for_kind = scratch_pad.setdefault(task.kind, {})
+    aliases = for_kind.setdefault("aliases", {})
+    alias_attribute = f"{task.kind}-alias"
+    if task.label in aliases:
+        raise Exception(
+            "Task `{}` has a {} of `{}`, masking a task of that name.".format(
+                aliases[task.label],
+                alias_attribute,
+                task.label[len(task.kind) + 1 :],
+            )
+        )
+    labels = for_kind.setdefault("labels", set())
+    labels.add(task.label)
+    attributes = task.attributes
+    if alias_attribute in attributes:
+        keys = attributes[alias_attribute]
+        if not keys:
+            keys = []
+        elif isinstance(keys, str):
+            keys = [keys]
+        for key in keys:
+            full_key = f"{task.kind}-{key}"
+            if full_key in labels:
+                raise Exception(
+                    "Task `{}` has a {} of `{}`,"
+                    " masking a task of that name.".format(
+                        task.label,
+                        alias_attribute,
+                        key,
+                    )
+                )
+            if full_key in aliases:
+                raise Exception(
+                    "Duplicate {} in tasks `{}`and `{}`: {}".format(
+                        alias_attribute,
+                        task.label,
+                        aliases[full_key],
+                        key,
+                    )
+                )
+            else:
+                aliases[full_key] = task.label
+
+
+@verifications.add("optimized_task_graph")
+def verify_always_optimized(task, taskgraph, scratch_pad, graph_config, parameters):
+    """
+    This function ensures that always-optimized tasks have been optimized.
+    """
+    if task is None:
+        return
+    if task.task.get("workerType") == "always-optimized":
+        raise Exception(f"Could not optimize the task {task.label!r}")
+
+
+@verifications.add("full_task_graph", run_on_projects=RELEASE_PROJECTS)
+def verify_shippable_no_sccache(task, taskgraph, scratch_pad, graph_config, parameters):
+    if task and task.attributes.get("shippable"):
+        if task.task.get("payload", {}).get("env", {}).get("USE_SCCACHE"):
+            raise Exception(f"Shippable job {task.label} cannot use sccache")
+
+
+@verifications.add("full_task_graph")
+def verify_test_packaging(task, taskgraph, scratch_pad, graph_config, parameters):
+    if task is None:
+        # In certain cases there are valid reasons for tests to be missing,
+        # don't error out when that happens.
+        missing_tests_allowed = any(
+            (
+                # user specified `--target-kind`
+                parameters.get("target-kind") is not None,
+                # manifest scheduling is enabled
+                parameters["test_manifest_loader"] != "default",
+            )
+        )
+
+        exceptions = []
+        for task in taskgraph.tasks.values():
+            if task.kind == "build" and not task.attributes.get(
+                "skip-verify-test-packaging"
+            ):
+                build_env = task.task.get("payload", {}).get("env", {})
+                package_tests = build_env.get("MOZ_AUTOMATION_PACKAGE_TESTS")
+                shippable = task.attributes.get("shippable", False)
+                build_has_tests = scratch_pad.get(task.label)
+
+                if package_tests != "1":
+                    # Shippable builds should always package tests.
+                    if shippable:
+                        exceptions.append(
+                            "Build job {} is shippable and does not specify "
+                            "MOZ_AUTOMATION_PACKAGE_TESTS=1 in the "
+                            "environment.".format(task.label)
+                        )
+
+                    # Build tasks in the scratch pad have tests dependent on
+                    # them, so we need to package tests during build.
+                    if build_has_tests:
+                        exceptions.append(
+                            "Build job {} has tests dependent on it and does not specify "
+                            "MOZ_AUTOMATION_PACKAGE_TESTS=1 in the environment".format(
+                                task.label
+                            )
+                        )
+                else:
+                    # Build tasks that aren't in the scratch pad have no
+                    # dependent tests, so we shouldn't package tests.
+                    # With the caveat that we expect shippable jobs to always
+                    # produce tests.
+                    if not build_has_tests and not shippable:
+                        # If we have not generated all task kinds, we can't verify that
+                        # there are no dependent tests.
+                        if not missing_tests_allowed:
+                            exceptions.append(
+                                "Build job {} has no tests, but specifies "
+                                "MOZ_AUTOMATION_PACKAGE_TESTS={} in the environment. "
+                                "Unset MOZ_AUTOMATION_PACKAGE_TESTS in the task definition "
+                                "to fix.".format(task.label, package_tests)
+                            )
+        if exceptions:
+            raise Exception("\n".join(exceptions))
+        return
+    if task.kind == "test":
+        build_task = taskgraph[task.dependencies["build"]]
+        scratch_pad[build_task.label] = 1
+
+
+@verifications.add("full_task_graph")
+def verify_run_known_projects(task, taskgraph, scratch_pad, graph_config, parameters):
+    """Validates the inputs in run-on-projects.
+
+    We should never let 'try' (or 'try-comm-central') be in run-on-projects even though it
+    is valid because it is not considered for try pushes.  While here we also validate for
+    other unknown projects or typos.
+    """
+    if task and task.attributes.get("run_on_projects"):
+        projects = set(task.attributes["run_on_projects"])
+        if {"try", "try-comm-central"} & set(projects):
+            raise Exception(
+                "In task {}: using try in run-on-projects is invalid; use try "
+                "selectors to select this task on try".format(task.label)
+            )
+        # try isn't valid, but by the time we get here its not an available project anyway.
+        valid_projects = ALL_PROJECTS | set(RUN_ON_PROJECT_ALIASES.keys())
+        invalid_projects = projects - valid_projects
+        if invalid_projects:
+            raise Exception(
+                "Task '{}' has an invalid run-on-projects value: "
+                "{}".format(task.label, invalid_projects)
+            )
diff --git a/taskcluster/gecko_taskgraph/util/workertypes.py b/taskcluster/gecko_taskgraph/util/workertypes.py
new file mode 100644
index 0000000000..b941ba85f6
--- /dev/null
+++ b/taskcluster/gecko_taskgraph/util/workertypes.py
@@ -0,0 +1,105 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from mozbuild.util import memoize
+from taskgraph.util.attributes import keymatch
+from taskgraph.util.keyed_by import evaluate_keyed_by
+
+from gecko_taskgraph.util.attributes import release_level as _release_level
+
+WORKER_TYPES = {
+    "gce/gecko-1-b-linux": ("docker-worker", "linux"),
+    "gce/gecko-2-b-linux": ("docker-worker", "linux"),
+    "gce/gecko-3-b-linux": ("docker-worker", "linux"),
+    "invalid/invalid": ("invalid", None),
+    "invalid/always-optimized": ("always-optimized", None),
+    "scriptworker-prov-v1/signing-linux-v1": ("scriptworker-signing", None),
+    "scriptworker-k8s/gecko-3-shipit": ("shipit", None),
+    "scriptworker-k8s/gecko-1-shipit": ("shipit", None),
+}
+
+
+@memoize
+def _get(graph_config, alias, level, release_level, project):
+    """Get the configuration for this worker_type alias: {provisioner,
+    worker-type, implementation, os}"""
+    level = str(level)
+
+    # handle the legacy (non-alias) format
+    if "/" in alias:
+        alias = alias.format(level=level)
+        provisioner, worker_type = alias.split("/", 1)
+        try:
+            implementation, os = WORKER_TYPES[alias]
+            return {
+                "provisioner": provisioner,
+                "worker-type": worker_type,
+                "implementation": implementation,
+                "os": os,
+            }
+        except KeyError:
+            return {
+                "provisioner": provisioner,
+                "worker-type": worker_type,
+            }
+
+    matches = keymatch(graph_config["workers"]["aliases"], alias)
+    if len(matches) > 1:
+        raise KeyError("Multiple matches for worker-type alias " + alias)
+    elif not matches:
+        raise KeyError("No matches for worker-type alias " + alias)
+    worker_config = matches[0].copy()
+
+    worker_config["provisioner"] = evaluate_keyed_by(
+        worker_config["provisioner"],
+        f"worker-type alias {alias} field provisioner",
+        {"level": level},
+    ).format(
+        **{
+            "trust-domain": graph_config["trust-domain"],
+            "level": level,
+            "alias": alias,
+        }
+    )
+    attrs = {"level": level, "release-level": release_level}
+    if project:
+        attrs["project"] = project
+    worker_config["worker-type"] = evaluate_keyed_by(
+        worker_config["worker-type"],
+        f"worker-type alias {alias} field worker-type",
+        attrs,
+    ).format(
+        **{
+            "trust-domain": graph_config["trust-domain"],
+            "level": level,
+            "alias": alias,
+        }
+    )
+
+    return worker_config
+
+
+def worker_type_implementation(graph_config, parameters, worker_type):
+    """Get the worker implementation and OS for the given workerType, where the
+    OS represents the host system, not the target OS, in the case of
+    cross-compiles."""
+    worker_config = _get(
+        graph_config, worker_type, "1", "staging", parameters["project"]
+    )
+    return worker_config["implementation"], worker_config.get("os")
+
+
+def get_worker_type(graph_config, parameters, worker_type):
+    """
+    Get the worker type provisioner and worker-type, optionally evaluating
+    aliases from the graph config.
+    """
+    worker_config = _get(
+        graph_config,
+        worker_type,
+        parameters["level"],
+        _release_level(parameters.get("project")),
+        parameters.get("project"),
+    )
+    return worker_config["provisioner"], worker_config["worker-type"]