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diff --git a/examples/my_commit_rules.py b/examples/my_commit_rules.py
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+from gitlint.rules import CommitRule, RuleViolation
+from gitlint.options import IntOption, ListOption
+
+"""
+Full details on user-defined rules: https://jorisroovers.com/gitlint/user_defined_rules
+
+The classes below are examples of user-defined CommitRules. Commit rules are gitlint rules that
+act on the entire commit at once. Once the rules are discovered, gitlint will automatically take care of applying them
+to the entire commit. This happens exactly once per commit.
+
+A CommitRule contrasts with a LineRule (see examples/my_line_rules.py) in that a commit rule is only applied once on
+an entire commit. This allows commit rules to implement more complex checks that span multiple lines and/or checks
+that should only be done once per gitlint run.
+
+While every LineRule can be implemented as a CommitRule, it's usually easier and more concise to go with a LineRule if
+that fits your needs.
+"""
+
+
+class BodyMaxLineCount(CommitRule):
+    # A rule MUST have a human friendly name
+    name = "body-max-line-count"
+
+    # A rule MUST have a *unique* id, we recommend starting with UC (for User-defined Commit-rule).
+    id = "UC1"
+
+    # A rule MAY have an option_spec if its behavior should be configurable.
+    options_spec = [IntOption("max-line-count", 3, "Maximum body line count")]
+
+    def validate(self, commit):
+        self.log.debug("BodyMaxLineCount: This will be visible when running `gitlint --debug`")
+
+        line_count = len(commit.message.body)
+        max_line_count = self.options["max-line-count"].value
+        if line_count > max_line_count:
+            message = f"Body contains too many lines ({line_count} > {max_line_count})"
+            return [RuleViolation(self.id, message, line_nr=1)]
+
+
+class SignedOffBy(CommitRule):
+    """This rule will enforce that each commit contains a "Signed-off-by" line.
+    We keep things simple here and just check whether the commit body contains a line that starts with "Signed-off-by".
+    """
+
+    # A rule MUST have a human friendly name
+    name = "body-requires-signed-off-by"
+
+    # A rule MUST have a *unique* id, we recommend starting with UC (for User-defined Commit-rule).
+    id = "UC2"
+
+    def validate(self, commit):
+        self.log.debug("SignedOffBy: This will be visible when running `gitlint --debug`")
+
+        for line in commit.message.body:
+            if line.startswith("Signed-off-by"):
+                return
+
+        return [RuleViolation(self.id, "Body does not contain a 'Signed-off-by' line", line_nr=1)]
+
+
+class BranchNamingConventions(CommitRule):
+    """This rule will enforce that a commit is part of a branch that meets certain naming conventions.
+    See GitFlow for real-world example of this: https://nvie.com/posts/a-successful-git-branching-model/
+    """
+
+    # A rule MUST have a human friendly name
+    name = "branch-naming-conventions"
+
+    # A rule MUST have a *unique* id, we recommend starting with UC (for User-defined Commit-rule).
+    id = "UC3"
+
+    # A rule MAY have an option_spec if its behavior should be configurable.
+    options_spec = [ListOption("branch-prefixes", ["feature/", "hotfix/", "release/"], "Allowed branch prefixes")]
+
+    def validate(self, commit):
+        self.log.debug("BranchNamingConventions: This line will be visible when running `gitlint --debug`")
+
+        violations = []
+        allowed_branch_prefixes = self.options["branch-prefixes"].value
+        for branch in commit.branches:
+            valid_branch_name = False
+
+            for allowed_prefix in allowed_branch_prefixes:
+                if branch.startswith(allowed_prefix):
+                    valid_branch_name = True
+                    break
+
+            if not valid_branch_name:
+                msg = f"Branch name '{branch}' does not start with one of {allowed_branch_prefixes}"
+                violations.append(RuleViolation(self.id, msg, line_nr=1))
+
+        return violations