Adding upstream version 5:7.2.4.upstream/5%7.2.4

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

40 files changed, 11032 insertions, 0 deletions

diff --git a/tests/modules/Makefile b/tests/modules/Makefile
new file mode 100644
index 0000000..d63c854
--- /dev/null
+++ b/tests/modules/Makefile
@@ -0,0 +1,83 @@
+
+# find the OS
+uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
+
+warning_cflags = -W -Wall -Wno-missing-field-initializers
+ifeq ($(uname_S),Darwin)
+	SHOBJ_CFLAGS ?= $(warning_cflags) -dynamic -fno-common -g -ggdb -std=c99 -O2
+	SHOBJ_LDFLAGS ?= -bundle -undefined dynamic_lookup
+else	# Linux, others
+	SHOBJ_CFLAGS ?= $(warning_cflags) -fno-common -g -ggdb -std=c99 -O2
+	SHOBJ_LDFLAGS ?= -shared
+endif
+
+ifeq ($(uname_S),Linux)
+    LD = gcc
+    CC = gcc
+endif
+
+# OS X 11.x doesn't have /usr/lib/libSystem.dylib and needs an explicit setting.
+ifeq ($(uname_S),Darwin)
+ifeq ("$(wildcard /usr/lib/libSystem.dylib)","")
+LIBS = -L /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib -lsystem
+endif
+endif
+
+TEST_MODULES = \
+    commandfilter.so \
+    basics.so \
+    testrdb.so \
+    fork.so \
+    infotest.so \
+    propagate.so \
+    misc.so \
+    hooks.so \
+    blockonkeys.so \
+    blockonbackground.so \
+    scan.so \
+    datatype.so \
+    datatype2.so \
+    auth.so \
+    keyspace_events.so \
+    blockedclient.so \
+    getkeys.so \
+    getchannels.so \
+    test_lazyfree.so \
+    timer.so \
+    defragtest.so \
+    keyspecs.so \
+    hash.so \
+    zset.so \
+    stream.so \
+    mallocsize.so \
+    aclcheck.so \
+    list.so \
+    subcommands.so \
+    reply.so \
+    cmdintrospection.so \
+    eventloop.so \
+    moduleconfigs.so \
+    moduleconfigstwo.so \
+    publish.so \
+    usercall.so \
+    postnotifications.so \
+    moduleauthtwo.so \
+    rdbloadsave.so
+
+.PHONY: all
+
+all: $(TEST_MODULES)
+
+32bit:
+	$(MAKE) CFLAGS="-m32" LDFLAGS="-m32"
+
+%.xo: %.c ../../src/redismodule.h
+	$(CC) -I../../src $(CFLAGS) $(SHOBJ_CFLAGS) -fPIC -c $< -o $@
+
+%.so: %.xo
+	$(LD) -o $@ $^ $(SHOBJ_LDFLAGS) $(LDFLAGS) $(LIBS)
+
+.PHONY: clean
+
+clean:
+	rm -f $(TEST_MODULES) $(TEST_MODULES:.so=.xo)
diff --git a/tests/modules/aclcheck.c b/tests/modules/aclcheck.c
new file mode 100644
index 0000000..09b525c
--- /dev/null
+++ b/tests/modules/aclcheck.c
@@ -0,0 +1,269 @@
+
+#include "redismodule.h"
+#include <errno.h>
+#include <assert.h>
+#include <string.h>
+#include <strings.h>
+
+/* A wrap for SET command with ACL check on the key. */
+int set_aclcheck_key(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 4) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    int permissions;
+    const char *flags = RedisModule_StringPtrLen(argv[1], NULL);
+
+    if (!strcasecmp(flags, "W")) {
+        permissions = REDISMODULE_CMD_KEY_UPDATE;
+    } else if (!strcasecmp(flags, "R")) {
+        permissions = REDISMODULE_CMD_KEY_ACCESS;
+    } else if (!strcasecmp(flags, "*")) {
+        permissions = REDISMODULE_CMD_KEY_UPDATE | REDISMODULE_CMD_KEY_ACCESS;
+    } else if (!strcasecmp(flags, "~")) {
+        permissions = 0; /* Requires either read or write */
+    } else {
+        RedisModule_ReplyWithError(ctx, "INVALID FLAGS");
+        return REDISMODULE_OK;
+    }
+
+    /* Check that the key can be accessed */
+    RedisModuleString *user_name = RedisModule_GetCurrentUserName(ctx);
+    RedisModuleUser *user = RedisModule_GetModuleUserFromUserName(user_name);
+    int ret = RedisModule_ACLCheckKeyPermissions(user, argv[2], permissions);
+    if (ret != 0) {
+        RedisModule_ReplyWithError(ctx, "DENIED KEY");
+        RedisModule_FreeModuleUser(user);
+        RedisModule_FreeString(ctx, user_name);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, "SET", "v", argv + 2, argc - 2);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    RedisModule_FreeModuleUser(user);
+    RedisModule_FreeString(ctx, user_name);
+    return REDISMODULE_OK;
+}
+
+/* A wrap for PUBLISH command with ACL check on the channel. */
+int publish_aclcheck_channel(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    /* Check that the pubsub channel can be accessed */
+    RedisModuleString *user_name = RedisModule_GetCurrentUserName(ctx);
+    RedisModuleUser *user = RedisModule_GetModuleUserFromUserName(user_name);
+    int ret = RedisModule_ACLCheckChannelPermissions(user, argv[1], REDISMODULE_CMD_CHANNEL_SUBSCRIBE);
+    if (ret != 0) {
+        RedisModule_ReplyWithError(ctx, "DENIED CHANNEL");
+        RedisModule_FreeModuleUser(user);
+        RedisModule_FreeString(ctx, user_name);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, "PUBLISH", "v", argv + 1, argc - 1);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    RedisModule_FreeModuleUser(user);
+    RedisModule_FreeString(ctx, user_name);
+    return REDISMODULE_OK;
+}
+
+/* A wrap for RM_Call that check first that the command can be executed */
+int rm_call_aclcheck_cmd(RedisModuleCtx *ctx, RedisModuleUser *user, RedisModuleString **argv, int argc) {
+    if (argc < 2) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    /* Check that the command can be executed */
+    int ret = RedisModule_ACLCheckCommandPermissions(user, argv + 1, argc - 1);
+    if (ret != 0) {
+        RedisModule_ReplyWithError(ctx, "DENIED CMD");
+        /* Add entry to ACL log */
+        RedisModule_ACLAddLogEntry(ctx, user, argv[1], REDISMODULE_ACL_LOG_CMD);
+        return REDISMODULE_OK;
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "v", argv + 2, argc - 2);
+    if(!rep){
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    }else{
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int rm_call_aclcheck_cmd_default_user(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModuleString *user_name = RedisModule_GetCurrentUserName(ctx);
+    RedisModuleUser *user = RedisModule_GetModuleUserFromUserName(user_name);
+
+    int res = rm_call_aclcheck_cmd(ctx, user, argv, argc);
+
+    RedisModule_FreeModuleUser(user);
+    RedisModule_FreeString(ctx, user_name);
+    return res;
+}
+
+int rm_call_aclcheck_cmd_module_user(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    /* Create a user and authenticate */
+    RedisModuleUser *user = RedisModule_CreateModuleUser("testuser1");
+    RedisModule_SetModuleUserACL(user, "allcommands");
+    RedisModule_SetModuleUserACL(user, "allkeys");
+    RedisModule_SetModuleUserACL(user, "on");
+    RedisModule_AuthenticateClientWithUser(ctx, user, NULL, NULL, NULL);
+
+    int res = rm_call_aclcheck_cmd(ctx, user, argv, argc);
+
+    /* authenticated back to "default" user (so once we free testuser1 we will not disconnected */
+    RedisModule_AuthenticateClientWithACLUser(ctx, "default", 7, NULL, NULL, NULL);
+    RedisModule_FreeModuleUser(user);
+    return res;
+}
+
+int rm_call_aclcheck_with_errors(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "vEC", argv + 2, argc - 2);
+    RedisModule_ReplyWithCallReply(ctx, rep);
+    RedisModule_FreeCallReply(rep);
+    return REDISMODULE_OK;
+}
+
+/* A wrap for RM_Call that pass the 'C' flag to do ACL check on the command. */
+int rm_call_aclcheck(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "vC", argv + 2, argc - 2);
+    if(!rep) {
+        char err[100];
+        switch (errno) {
+            case EACCES:
+                RedisModule_ReplyWithError(ctx, "ERR NOPERM");
+                break;
+            default:
+                snprintf(err, sizeof(err) - 1, "ERR errno=%d", errno);
+                RedisModule_ReplyWithError(ctx, err);
+                break;
+        }
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int module_test_acl_category(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int commandBlockCheck(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    int response_ok = 0;
+    int result = RedisModule_CreateCommand(ctx,"command.that.should.fail", module_test_acl_category, "", 0, 0, 0);
+    response_ok |= (result == REDISMODULE_OK);
+
+    RedisModuleCommand *parent = RedisModule_GetCommand(ctx,"block.commands.outside.onload");
+    result = RedisModule_SetCommandACLCategories(parent, "write");
+    response_ok |= (result == REDISMODULE_OK);
+
+    result = RedisModule_CreateSubcommand(parent,"subcommand.that.should.fail",module_test_acl_category,"",0,0,0);
+    response_ok |= (result == REDISMODULE_OK);
+    
+    /* This validates that it's not possible to create commands outside OnLoad,
+     * thus returns an error if they succeed. */
+    if (response_ok) {
+        RedisModule_ReplyWithError(ctx, "UNEXPECTEDOK");
+    } else {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    }
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"aclcheck",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.set.check.key", set_aclcheck_key,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.commands.outside.onload", commandBlockCheck,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.module.command.aclcategories.write", module_test_acl_category,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    RedisModuleCommand *aclcategories_write = RedisModule_GetCommand(ctx,"aclcheck.module.command.aclcategories.write");
+
+    if (RedisModule_SetCommandACLCategories(aclcategories_write, "write") == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.module.command.aclcategories.write.function.read.category", module_test_acl_category,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    RedisModuleCommand *read_category = RedisModule_GetCommand(ctx,"aclcheck.module.command.aclcategories.write.function.read.category");
+
+    if (RedisModule_SetCommandACLCategories(read_category, "read") == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.module.command.aclcategories.read.only.category", module_test_acl_category,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    RedisModuleCommand *read_only_category = RedisModule_GetCommand(ctx,"aclcheck.module.command.aclcategories.read.only.category");
+
+    if (RedisModule_SetCommandACLCategories(read_only_category, "read") == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.publish.check.channel", publish_aclcheck_channel,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.rm_call.check.cmd", rm_call_aclcheck_cmd_default_user,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.rm_call.check.cmd.module.user", rm_call_aclcheck_cmd_module_user,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.rm_call", rm_call_aclcheck,
+                                  "write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"aclcheck.rm_call_with_errors", rm_call_aclcheck_with_errors,
+                                      "write",0,0,0) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/auth.c b/tests/modules/auth.c
new file mode 100644
index 0000000..19be95a
--- /dev/null
+++ b/tests/modules/auth.c
@@ -0,0 +1,270 @@
+/* define macros for having usleep */
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE
+
+#include "redismodule.h"
+
+#include <string.h>
+#include <unistd.h>
+#include <pthread.h>
+
+#define UNUSED(V) ((void) V)
+
+// A simple global user
+static RedisModuleUser *global = NULL;
+static long long client_change_delta = 0;
+
+void UserChangedCallback(uint64_t client_id, void *privdata) {
+    REDISMODULE_NOT_USED(privdata);
+    REDISMODULE_NOT_USED(client_id);
+    client_change_delta++;
+}
+
+int Auth_CreateModuleUser(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (global) {
+        RedisModule_FreeModuleUser(global);
+    }
+
+    global = RedisModule_CreateModuleUser("global");
+    RedisModule_SetModuleUserACL(global, "allcommands");
+    RedisModule_SetModuleUserACL(global, "allkeys");
+    RedisModule_SetModuleUserACL(global, "on");
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+int Auth_AuthModuleUser(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    uint64_t client_id;
+    RedisModule_AuthenticateClientWithUser(ctx, global, UserChangedCallback, NULL, &client_id);
+
+    return RedisModule_ReplyWithLongLong(ctx, (uint64_t) client_id);
+}
+
+int Auth_AuthRealUser(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    size_t length;
+    uint64_t client_id;
+
+    RedisModuleString *user_string = argv[1];
+    const char *name = RedisModule_StringPtrLen(user_string, &length);
+
+    if (RedisModule_AuthenticateClientWithACLUser(ctx, name, length, 
+            UserChangedCallback, NULL, &client_id) == REDISMODULE_ERR) {
+        return RedisModule_ReplyWithError(ctx, "Invalid user");   
+    }
+
+    return RedisModule_ReplyWithLongLong(ctx, (uint64_t) client_id);
+}
+
+/* This command redacts every other arguments and returns OK */
+int Auth_RedactedAPI(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    for(int i = argc - 1; i > 0; i -= 2) {
+        int result = RedisModule_RedactClientCommandArgument(ctx, i);
+        RedisModule_Assert(result == REDISMODULE_OK);
+    }
+    return RedisModule_ReplyWithSimpleString(ctx, "OK"); 
+}
+
+int Auth_ChangeCount(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    long long result = client_change_delta;
+    client_change_delta = 0;
+    return RedisModule_ReplyWithLongLong(ctx, result);
+}
+
+/* The Module functionality below validates that module authentication callbacks can be registered
+ * to support both non-blocking and blocking module based authentication. */
+
+/* Non Blocking Module Auth callback / implementation. */
+int auth_cb(RedisModuleCtx *ctx, RedisModuleString *username, RedisModuleString *password, RedisModuleString **err) {
+    const char *user = RedisModule_StringPtrLen(username, NULL);
+    const char *pwd = RedisModule_StringPtrLen(password, NULL);
+    if (!strcmp(user,"foo") && !strcmp(pwd,"allow")) {
+        RedisModule_AuthenticateClientWithACLUser(ctx, "foo", 3, NULL, NULL, NULL);
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    else if (!strcmp(user,"foo") && !strcmp(pwd,"deny")) {
+        RedisModuleString *log = RedisModule_CreateString(ctx, "Module Auth", 11);
+        RedisModule_ACLAddLogEntryByUserName(ctx, username, log, REDISMODULE_ACL_LOG_AUTH);
+        RedisModule_FreeString(ctx, log);
+        const char *err_msg = "Auth denied by Misc Module.";
+        *err = RedisModule_CreateString(ctx, err_msg, strlen(err_msg));
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    return REDISMODULE_AUTH_NOT_HANDLED;
+}
+
+int test_rm_register_auth_cb(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_RegisterAuthCallback(ctx, auth_cb);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/*
+ * The thread entry point that actually executes the blocking part of the AUTH command.
+ * This function sleeps for 0.5 seconds and then unblocks the client which will later call
+ * `AuthBlock_Reply`.
+ * `arg` is expected to contain the RedisModuleBlockedClient, username, and password.
+ */
+void *AuthBlock_ThreadMain(void *arg) {
+    usleep(500000);
+    void **targ = arg;
+    RedisModuleBlockedClient *bc = targ[0];
+    int result = 2;
+    const char *user = RedisModule_StringPtrLen(targ[1], NULL);
+    const char *pwd = RedisModule_StringPtrLen(targ[2], NULL);
+    if (!strcmp(user,"foo") && !strcmp(pwd,"block_allow")) {
+        result = 1;
+    }
+    else if (!strcmp(user,"foo") && !strcmp(pwd,"block_deny")) {
+        result = 0;
+    }
+    else if (!strcmp(user,"foo") && !strcmp(pwd,"block_abort")) {
+        RedisModule_BlockedClientMeasureTimeEnd(bc);
+        RedisModule_AbortBlock(bc);
+        goto cleanup;
+    }
+    /* Provide the result to the blocking reply cb. */
+    void **replyarg = RedisModule_Alloc(sizeof(void*));
+    replyarg[0] = (void *) (uintptr_t) result;
+    RedisModule_BlockedClientMeasureTimeEnd(bc);
+    RedisModule_UnblockClient(bc, replyarg);
+cleanup:
+    /* Free the username and password and thread / arg data. */
+    RedisModule_FreeString(NULL, targ[1]);
+    RedisModule_FreeString(NULL, targ[2]);
+    RedisModule_Free(targ);
+    return NULL;
+}
+
+/*
+ * Reply callback for a blocking AUTH command. This is called when the client is unblocked.
+ */
+int AuthBlock_Reply(RedisModuleCtx *ctx, RedisModuleString *username, RedisModuleString *password, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(password);
+    void **targ = RedisModule_GetBlockedClientPrivateData(ctx);
+    int result = (uintptr_t) targ[0];
+    size_t userlen = 0;
+    const char *user = RedisModule_StringPtrLen(username, &userlen);
+    /* Handle the success case by authenticating. */
+    if (result == 1) {
+        RedisModule_AuthenticateClientWithACLUser(ctx, user, userlen, NULL, NULL, NULL);
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    /* Handle the Error case by denying auth */
+    else if (result == 0) {
+        RedisModuleString *log = RedisModule_CreateString(ctx, "Module Auth", 11);
+        RedisModule_ACLAddLogEntryByUserName(ctx, username, log, REDISMODULE_ACL_LOG_AUTH);
+        RedisModule_FreeString(ctx, log);
+        const char *err_msg = "Auth denied by Misc Module.";
+        *err = RedisModule_CreateString(ctx, err_msg, strlen(err_msg));
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    /* "Skip" Authentication */
+    return REDISMODULE_AUTH_NOT_HANDLED;
+}
+
+/* Private data freeing callback for Module Auth. */
+void AuthBlock_FreeData(RedisModuleCtx *ctx, void *privdata) {
+    REDISMODULE_NOT_USED(ctx);
+    RedisModule_Free(privdata);
+}
+
+/* Callback triggered when the engine attempts module auth
+ * Return code here is one of the following: Auth succeeded, Auth denied,
+ * Auth not handled, Auth blocked.
+ * The Module can have auth succeed / denied here itself, but this is an example
+ * of blocking module auth.
+ */
+int blocking_auth_cb(RedisModuleCtx *ctx, RedisModuleString *username, RedisModuleString *password, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(username);
+    REDISMODULE_NOT_USED(password);
+    REDISMODULE_NOT_USED(err);
+    /* Block the client from the Module. */
+    RedisModuleBlockedClient *bc = RedisModule_BlockClientOnAuth(ctx, AuthBlock_Reply, AuthBlock_FreeData);
+    int ctx_flags = RedisModule_GetContextFlags(ctx);
+    if (ctx_flags & REDISMODULE_CTX_FLAGS_MULTI || ctx_flags & REDISMODULE_CTX_FLAGS_LUA) {
+        /* Clean up by using RedisModule_UnblockClient since we attempted blocking the client. */
+        RedisModule_UnblockClient(bc, NULL);
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    RedisModule_BlockedClientMeasureTimeStart(bc);
+    pthread_t tid;
+    /* Allocate memory for information needed. */
+    void **targ = RedisModule_Alloc(sizeof(void*)*3);
+    targ[0] = bc;
+    targ[1] = RedisModule_CreateStringFromString(NULL, username);
+    targ[2] = RedisModule_CreateStringFromString(NULL, password);
+    /* Create bg thread and pass the blockedclient, username and password to it. */
+    if (pthread_create(&tid, NULL, AuthBlock_ThreadMain, targ) != 0) {
+        RedisModule_AbortBlock(bc);
+    }
+    return REDISMODULE_AUTH_HANDLED;
+}
+
+int test_rm_register_blocking_auth_cb(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_RegisterAuthCallback(ctx, blocking_auth_cb);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* This function must be present on each Redis module. It is used in order to
+ * register the commands into the Redis server. */
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"testacl",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"auth.authrealuser",
+        Auth_AuthRealUser,"no-auth",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"auth.createmoduleuser",
+        Auth_CreateModuleUser,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"auth.authmoduleuser",
+        Auth_AuthModuleUser,"no-auth",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"auth.changecount",
+        Auth_ChangeCount,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"auth.redact",
+        Auth_RedactedAPI,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testmoduleone.rm_register_auth_cb",
+        test_rm_register_auth_cb,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testmoduleone.rm_register_blocking_auth_cb",
+        test_rm_register_blocking_auth_cb,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    UNUSED(ctx);
+
+    if (global)
+        RedisModule_FreeModuleUser(global);
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/basics.c b/tests/modules/basics.c
new file mode 100644
index 0000000..897cb5d
--- /dev/null
+++ b/tests/modules/basics.c
@@ -0,0 +1,1052 @@
+/* Module designed to test the Redis modules subsystem.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2016, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "redismodule.h"
+#include <string.h>
+#include <stdlib.h>
+
+/* --------------------------------- Helpers -------------------------------- */
+
+/* Return true if the reply and the C null term string matches. */
+int TestMatchReply(RedisModuleCallReply *reply, char *str) {
+    RedisModuleString *mystr;
+    mystr = RedisModule_CreateStringFromCallReply(reply);
+    if (!mystr) return 0;
+    const char *ptr = RedisModule_StringPtrLen(mystr,NULL);
+    return strcmp(ptr,str) == 0;
+}
+
+/* ------------------------------- Test units ------------------------------- */
+
+/* TEST.CALL -- Test Call() API. */
+int TestCall(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","mylist");
+    RedisModuleString *mystr = RedisModule_CreateString(ctx,"foo",3);
+    RedisModule_Call(ctx,"RPUSH","csl","mylist",mystr,(long long)1234);
+    reply = RedisModule_Call(ctx,"LRANGE","ccc","mylist","0","-1");
+    long long items = RedisModule_CallReplyLength(reply);
+    if (items != 2) goto fail;
+
+    RedisModuleCallReply *item0, *item1;
+
+    item0 = RedisModule_CallReplyArrayElement(reply,0);
+    item1 = RedisModule_CallReplyArrayElement(reply,1);
+    if (!TestMatchReply(item0,"foo")) goto fail;
+    if (!TestMatchReply(item1,"1234")) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Attribute(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "attrib"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_STRING) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 (it might be a string but it contains attribute) */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    if (!TestMatchReply(reply,"Some real reply following the attribute")) goto fail;
+
+    reply = RedisModule_CallReplyAttribute(reply);
+    if (!reply || RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_ATTRIBUTE) goto fail;
+    /* make sure we can not reply to resp2 client with resp3 attribute */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+    if (RedisModule_CallReplyLength(reply) != 1) goto fail;
+
+    RedisModuleCallReply *key, *val;
+    if (RedisModule_CallReplyAttributeElement(reply,0,&key,&val) != REDISMODULE_OK) goto fail;
+    if (!TestMatchReply(key,"key-popularity")) goto fail;
+    if (RedisModule_CallReplyType(val) != REDISMODULE_REPLY_ARRAY) goto fail;
+    if (RedisModule_CallReplyLength(val) != 2) goto fail;
+    if (!TestMatchReply(RedisModule_CallReplyArrayElement(val, 0),"key:123")) goto fail;
+    if (!TestMatchReply(RedisModule_CallReplyArrayElement(val, 1),"90")) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestGetResp(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    int flags = RedisModule_GetContextFlags(ctx);
+
+    if (flags & REDISMODULE_CTX_FLAGS_RESP3) {
+        RedisModule_ReplyWithLongLong(ctx, 3);
+    } else {
+        RedisModule_ReplyWithLongLong(ctx, 2);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int TestCallRespAutoMode(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","myhash");
+    RedisModule_Call(ctx,"HSET","ccccc","myhash", "f1", "v1", "f2", "v2");
+    /* 0 stands for auto mode, we will get the reply in the same format as the client */
+    reply = RedisModule_Call(ctx,"HGETALL","0c" ,"myhash");
+    RedisModule_ReplyWithCallReply(ctx, reply);
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Map(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","myhash");
+    RedisModule_Call(ctx,"HSET","ccccc","myhash", "f1", "v1", "f2", "v2");
+    reply = RedisModule_Call(ctx,"HGETALL","3c" ,"myhash"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_MAP) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 map */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    long long items = RedisModule_CallReplyLength(reply);
+    if (items != 2) goto fail;
+
+    RedisModuleCallReply *key0, *key1;
+    RedisModuleCallReply *val0, *val1;
+    if (RedisModule_CallReplyMapElement(reply,0,&key0,&val0) != REDISMODULE_OK) goto fail;
+    if (RedisModule_CallReplyMapElement(reply,1,&key1,&val1) != REDISMODULE_OK) goto fail;
+    if (!TestMatchReply(key0,"f1")) goto fail;
+    if (!TestMatchReply(key1,"f2")) goto fail;
+    if (!TestMatchReply(val0,"v1")) goto fail;
+    if (!TestMatchReply(val1,"v2")) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Bool(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "true"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_BOOL) goto fail;
+    /* make sure we can not reply to resp2 client with resp3 bool */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    if (!RedisModule_CallReplyBool(reply)) goto fail;
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "false"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_BOOL) goto fail;
+    if (RedisModule_CallReplyBool(reply)) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Null(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "null"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_NULL) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 null */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallReplyWithNestedReply(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","mylist");
+    RedisModule_Call(ctx,"RPUSH","ccl","mylist","test",(long long)1234);
+    reply = RedisModule_Call(ctx,"LRANGE","ccc","mylist","0","-1");
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_ARRAY) goto fail;
+    if (RedisModule_CallReplyLength(reply) < 1) goto fail;
+    RedisModuleCallReply *nestedReply = RedisModule_CallReplyArrayElement(reply, 0);
+
+    RedisModule_ReplyWithCallReply(ctx,nestedReply);
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallReplyWithArrayReply(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","mylist");
+    RedisModule_Call(ctx,"RPUSH","ccl","mylist","test",(long long)1234);
+    reply = RedisModule_Call(ctx,"LRANGE","ccc","mylist","0","-1");
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_ARRAY) goto fail;
+
+    RedisModule_ReplyWithCallReply(ctx,reply);
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Double(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "double"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_DOUBLE) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 double*/
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    double d = RedisModule_CallReplyDouble(reply);
+    /* we compare strings, since comparing doubles directly can fail in various architectures, e.g. 32bit */
+    char got[30], expected[30];
+    snprintf(got, sizeof(got), "%.17g", d);
+    snprintf(expected, sizeof(expected), "%.17g", 3.141);
+    if (strcmp(got, expected) != 0) goto fail;
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3BigNumber(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "bignum"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_BIG_NUMBER) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 big number */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    size_t len;
+    const char* big_num = RedisModule_CallReplyBigNumber(reply, &len);
+    RedisModule_ReplyWithStringBuffer(ctx,big_num,len);
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Verbatim(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx,"DEBUG","3cc" ,"PROTOCOL", "verbatim"); /* 3 stands for resp 3 reply */
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_VERBATIM_STRING) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 verbatim string */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    const char* format;
+    size_t len;
+    const char* str = RedisModule_CallReplyVerbatim(reply, &len, &format);
+    RedisModuleString *s = RedisModule_CreateStringPrintf(ctx, "%.*s:%.*s", 3, format, (int)len, str);
+    RedisModule_ReplyWithString(ctx,s);
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+int TestCallResp3Set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    RedisModule_Call(ctx,"DEL","c","myset");
+    RedisModule_Call(ctx,"sadd","ccc","myset", "v1", "v2");
+    reply = RedisModule_Call(ctx,"smembers","3c" ,"myset"); // N stands for resp 3 reply
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_SET) goto fail;
+
+    /* make sure we can not reply to resp2 client with resp3 set */
+    if (RedisModule_ReplyWithCallReply(ctx, reply) != REDISMODULE_ERR) goto fail;
+
+    long long items = RedisModule_CallReplyLength(reply);
+    if (items != 2) goto fail;
+
+    RedisModuleCallReply *val0, *val1;
+
+    val0 = RedisModule_CallReplySetElement(reply,0);
+    val1 = RedisModule_CallReplySetElement(reply,1);
+
+    /*
+     * The order of elements on sets are not promised so we just
+     * veridy that the reply matches one of the elements.
+     */
+    if (!TestMatchReply(val0,"v1") && !TestMatchReply(val0,"v2")) goto fail;
+    if (!TestMatchReply(val1,"v1") && !TestMatchReply(val1,"v2")) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,"ERR");
+    return REDISMODULE_OK;
+}
+
+/* TEST.STRING.APPEND -- Test appending to an existing string object. */
+int TestStringAppend(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleString *s = RedisModule_CreateString(ctx,"foo",3);
+    RedisModule_StringAppendBuffer(ctx,s,"bar",3);
+    RedisModule_ReplyWithString(ctx,s);
+    RedisModule_FreeString(ctx,s);
+    return REDISMODULE_OK;
+}
+
+/* TEST.STRING.APPEND.AM -- Test append with retain when auto memory is on. */
+int TestStringAppendAM(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleString *s = RedisModule_CreateString(ctx,"foo",3);
+    RedisModule_RetainString(ctx,s);
+    RedisModule_TrimStringAllocation(s);    /* Mostly NOP, but exercises the API function */
+    RedisModule_StringAppendBuffer(ctx,s,"bar",3);
+    RedisModule_ReplyWithString(ctx,s);
+    RedisModule_FreeString(ctx,s);
+    return REDISMODULE_OK;
+}
+
+/* TEST.STRING.TRIM -- Test we trim a string with free space. */
+int TestTrimString(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleString *s = RedisModule_CreateString(ctx,"foo",3);
+    char *tmp = RedisModule_Alloc(1024);
+    RedisModule_StringAppendBuffer(ctx,s,tmp,1024);
+    size_t string_len = RedisModule_MallocSizeString(s);
+    RedisModule_TrimStringAllocation(s);
+    size_t len_after_trim = RedisModule_MallocSizeString(s);
+
+    /* Determine if using jemalloc memory allocator. */
+    RedisModuleServerInfoData *info = RedisModule_GetServerInfo(ctx, "memory");
+    const char *field = RedisModule_ServerInfoGetFieldC(info, "mem_allocator");
+    int use_jemalloc = !strncmp(field, "jemalloc", 8);
+
+    /* Jemalloc will reallocate `s` from 2k to 1k after RedisModule_TrimStringAllocation(),
+     * but non-jemalloc memory allocators may keep the old size. */
+    if ((use_jemalloc && len_after_trim < string_len) ||
+        (!use_jemalloc && len_after_trim <= string_len))
+    {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        RedisModule_ReplyWithError(ctx, "String was not trimmed as expected.");
+    }
+    RedisModule_FreeServerInfo(ctx, info);
+    RedisModule_Free(tmp);
+    RedisModule_FreeString(ctx,s);
+    return REDISMODULE_OK;
+}
+
+/* TEST.STRING.PRINTF -- Test string formatting. */
+int TestStringPrintf(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);
+    if (argc < 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+    RedisModuleString *s = RedisModule_CreateStringPrintf(ctx,
+        "Got %d args. argv[1]: %s, argv[2]: %s",
+        argc,
+        RedisModule_StringPtrLen(argv[1], NULL),
+        RedisModule_StringPtrLen(argv[2], NULL)
+    );
+
+    RedisModule_ReplyWithString(ctx,s);
+
+    return REDISMODULE_OK;
+}
+
+int failTest(RedisModuleCtx *ctx, const char *msg) {
+    RedisModule_ReplyWithError(ctx, msg);
+    return REDISMODULE_ERR;
+}
+
+int TestUnlink(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleKey *k = RedisModule_OpenKey(ctx, RedisModule_CreateStringPrintf(ctx, "unlinked"), REDISMODULE_WRITE | REDISMODULE_READ);
+    if (!k) return failTest(ctx, "Could not create key");
+
+    if (REDISMODULE_ERR == RedisModule_StringSet(k, RedisModule_CreateStringPrintf(ctx, "Foobar"))) {
+        return failTest(ctx, "Could not set string value");
+    }
+
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, "EXISTS", "c", "unlinked");
+    if (!rep || RedisModule_CallReplyInteger(rep) != 1) {
+        return failTest(ctx, "Key does not exist before unlink");
+    }
+
+    if (REDISMODULE_ERR == RedisModule_UnlinkKey(k)) {
+        return failTest(ctx, "Could not unlink key");
+    }
+
+    rep = RedisModule_Call(ctx, "EXISTS", "c", "unlinked");
+    if (!rep || RedisModule_CallReplyInteger(rep) != 0) {
+        return failTest(ctx, "Could not verify key to be unlinked");
+    }
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+int TestNestedCallReplyArrayElement(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleString *expect_key = RedisModule_CreateString(ctx, "mykey", strlen("mykey"));
+    RedisModule_SelectDb(ctx, 1);
+    RedisModule_Call(ctx, "LPUSH", "sc", expect_key, "myvalue");
+
+    RedisModuleCallReply *scan_reply = RedisModule_Call(ctx, "SCAN", "l", (long long)0);
+    RedisModule_Assert(scan_reply != NULL && RedisModule_CallReplyType(scan_reply) == REDISMODULE_REPLY_ARRAY);
+    RedisModule_Assert(RedisModule_CallReplyLength(scan_reply) == 2);
+
+    long long scan_cursor;
+    RedisModuleCallReply *cursor_reply = RedisModule_CallReplyArrayElement(scan_reply, 0);
+    RedisModule_Assert(RedisModule_CallReplyType(cursor_reply) == REDISMODULE_REPLY_STRING);
+    RedisModule_Assert(RedisModule_StringToLongLong(RedisModule_CreateStringFromCallReply(cursor_reply), &scan_cursor) == REDISMODULE_OK);
+    RedisModule_Assert(scan_cursor == 0);
+
+    RedisModuleCallReply *keys_reply = RedisModule_CallReplyArrayElement(scan_reply, 1);
+    RedisModule_Assert(RedisModule_CallReplyType(keys_reply) == REDISMODULE_REPLY_ARRAY);
+    RedisModule_Assert( RedisModule_CallReplyLength(keys_reply) == 1);
+ 
+    RedisModuleCallReply *key_reply = RedisModule_CallReplyArrayElement(keys_reply, 0);
+    RedisModule_Assert(RedisModule_CallReplyType(key_reply) == REDISMODULE_REPLY_STRING);
+    RedisModuleString *key = RedisModule_CreateStringFromCallReply(key_reply);
+    RedisModule_Assert(RedisModule_StringCompare(key, expect_key) == 0);
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* TEST.STRING.TRUNCATE -- Test truncating an existing string object. */
+int TestStringTruncate(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_Call(ctx, "SET", "cc", "foo", "abcde");
+    RedisModuleKey *k = RedisModule_OpenKey(ctx, RedisModule_CreateStringPrintf(ctx, "foo"), REDISMODULE_READ | REDISMODULE_WRITE);
+    if (!k) return failTest(ctx, "Could not create key");
+
+    size_t len = 0;
+    char* s;
+
+    /* expand from 5 to 8 and check null pad */
+    if (REDISMODULE_ERR == RedisModule_StringTruncate(k, 8)) {
+        return failTest(ctx, "Could not truncate string value (8)");
+    }
+    s = RedisModule_StringDMA(k, &len, REDISMODULE_READ);
+    if (!s) {
+        return failTest(ctx, "Failed to read truncated string (8)");
+    } else if (len != 8) {
+        return failTest(ctx, "Failed to expand string value (8)");
+    } else if (0 != strncmp(s, "abcde\0\0\0", 8)) {
+        return failTest(ctx, "Failed to null pad string value (8)");
+    }
+
+    /* shrink from 8 to 4 */
+    if (REDISMODULE_ERR == RedisModule_StringTruncate(k, 4)) {
+        return failTest(ctx, "Could not truncate string value (4)");
+    }
+    s = RedisModule_StringDMA(k, &len, REDISMODULE_READ);
+    if (!s) {
+        return failTest(ctx, "Failed to read truncated string (4)");
+    } else if (len != 4) {
+        return failTest(ctx, "Failed to shrink string value (4)");
+    } else if (0 != strncmp(s, "abcd", 4)) {
+        return failTest(ctx, "Failed to truncate string value (4)");
+    }
+
+    /* shrink to 0 */
+    if (REDISMODULE_ERR == RedisModule_StringTruncate(k, 0)) {
+        return failTest(ctx, "Could not truncate string value (0)");
+    }
+    s = RedisModule_StringDMA(k, &len, REDISMODULE_READ);
+    if (!s) {
+        return failTest(ctx, "Failed to read truncated string (0)");
+    } else if (len != 0) {
+        return failTest(ctx, "Failed to shrink string value to (0)");
+    }
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+int NotifyCallback(RedisModuleCtx *ctx, int type, const char *event,
+                   RedisModuleString *key) {
+  RedisModule_AutoMemory(ctx);
+  /* Increment a counter on the notifications: for each key notified we
+   * increment a counter */
+  RedisModule_Log(ctx, "notice", "Got event type %d, event %s, key %s", type,
+                  event, RedisModule_StringPtrLen(key, NULL));
+
+  RedisModule_Call(ctx, "HINCRBY", "csc", "notifications", key, "1");
+  return REDISMODULE_OK;
+}
+
+/* TEST.NOTIFICATIONS -- Test Keyspace Notifications. */
+int TestNotifications(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+#define FAIL(msg, ...)                                                                       \
+    {                                                                                        \
+        RedisModule_Log(ctx, "warning", "Failed NOTIFY Test. Reason: " #msg, ##__VA_ARGS__); \
+        goto err;                                                                            \
+    }
+    RedisModule_Call(ctx, "FLUSHDB", "");
+
+    RedisModule_Call(ctx, "SET", "cc", "foo", "bar");
+    RedisModule_Call(ctx, "SET", "cc", "foo", "baz");
+    RedisModule_Call(ctx, "SADD", "cc", "bar", "x");
+    RedisModule_Call(ctx, "SADD", "cc", "bar", "y");
+
+    RedisModule_Call(ctx, "HSET", "ccc", "baz", "x", "y");
+    /* LPUSH should be ignored and not increment any counters */
+    RedisModule_Call(ctx, "LPUSH", "cc", "l", "y");
+    RedisModule_Call(ctx, "LPUSH", "cc", "l", "y");
+
+    /* Miss some keys intentionally so we will get a "keymiss" notification. */
+    RedisModule_Call(ctx, "GET", "c", "nosuchkey");
+    RedisModule_Call(ctx, "SMEMBERS", "c", "nosuchkey");
+
+    size_t sz;
+    const char *rep;
+    RedisModuleCallReply *r = RedisModule_Call(ctx, "HGET", "cc", "notifications", "foo");
+    if (r == NULL || RedisModule_CallReplyType(r) != REDISMODULE_REPLY_STRING) {
+        FAIL("Wrong or no reply for foo");
+    } else {
+        rep = RedisModule_CallReplyStringPtr(r, &sz);
+        if (sz != 1 || *rep != '2') {
+            FAIL("Got reply '%s'. expected '2'", RedisModule_CallReplyStringPtr(r, NULL));
+        }
+    }
+
+    r = RedisModule_Call(ctx, "HGET", "cc", "notifications", "bar");
+    if (r == NULL || RedisModule_CallReplyType(r) != REDISMODULE_REPLY_STRING) {
+        FAIL("Wrong or no reply for bar");
+    } else {
+        rep = RedisModule_CallReplyStringPtr(r, &sz);
+        if (sz != 1 || *rep != '2') {
+            FAIL("Got reply '%s'. expected '2'", rep);
+        }
+    }
+
+    r = RedisModule_Call(ctx, "HGET", "cc", "notifications", "baz");
+    if (r == NULL || RedisModule_CallReplyType(r) != REDISMODULE_REPLY_STRING) {
+        FAIL("Wrong or no reply for baz");
+    } else {
+        rep = RedisModule_CallReplyStringPtr(r, &sz);
+        if (sz != 1 || *rep != '1') {
+            FAIL("Got reply '%.*s'. expected '1'", (int)sz, rep);
+        }
+    }
+    /* For l we expect nothing since we didn't subscribe to list events */
+    r = RedisModule_Call(ctx, "HGET", "cc", "notifications", "l");
+    if (r == NULL || RedisModule_CallReplyType(r) != REDISMODULE_REPLY_NULL) {
+        FAIL("Wrong reply for l");
+    }
+
+    r = RedisModule_Call(ctx, "HGET", "cc", "notifications", "nosuchkey");
+    if (r == NULL || RedisModule_CallReplyType(r) != REDISMODULE_REPLY_STRING) {
+        FAIL("Wrong or no reply for nosuchkey");
+    } else {
+        rep = RedisModule_CallReplyStringPtr(r, &sz);
+        if (sz != 1 || *rep != '2') {
+            FAIL("Got reply '%.*s'. expected '2'", (int)sz, rep);
+        }
+    }
+
+    RedisModule_Call(ctx, "FLUSHDB", "");
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+err:
+    RedisModule_Call(ctx, "FLUSHDB", "");
+
+    return RedisModule_ReplyWithSimpleString(ctx, "ERR");
+}
+
+/* TEST.CTXFLAGS -- Test GetContextFlags. */
+int TestCtxFlags(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argc);
+    REDISMODULE_NOT_USED(argv);
+
+    RedisModule_AutoMemory(ctx);
+
+    int ok = 1;
+    const char *errString = NULL;
+#undef FAIL
+#define FAIL(msg)        \
+    {                    \
+        ok = 0;          \
+        errString = msg; \
+        goto end;        \
+    }
+
+    int flags = RedisModule_GetContextFlags(ctx);
+    if (flags == 0) {
+        FAIL("Got no flags");
+    }
+
+    if (flags & REDISMODULE_CTX_FLAGS_LUA) FAIL("Lua flag was set");
+    if (flags & REDISMODULE_CTX_FLAGS_MULTI) FAIL("Multi flag was set");
+
+    if (flags & REDISMODULE_CTX_FLAGS_AOF) FAIL("AOF Flag was set")
+    /* Enable AOF to test AOF flags */
+    RedisModule_Call(ctx, "config", "ccc", "set", "appendonly", "yes");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (!(flags & REDISMODULE_CTX_FLAGS_AOF)) FAIL("AOF Flag not set after config set");
+
+    /* Disable RDB saving and test the flag. */
+    RedisModule_Call(ctx, "config", "ccc", "set", "save", "");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (flags & REDISMODULE_CTX_FLAGS_RDB) FAIL("RDB Flag was set");
+    /* Enable RDB to test RDB flags */
+    RedisModule_Call(ctx, "config", "ccc", "set", "save", "900 1");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (!(flags & REDISMODULE_CTX_FLAGS_RDB)) FAIL("RDB Flag was not set after config set");
+
+    if (!(flags & REDISMODULE_CTX_FLAGS_MASTER)) FAIL("Master flag was not set");
+    if (flags & REDISMODULE_CTX_FLAGS_SLAVE) FAIL("Slave flag was set");
+    if (flags & REDISMODULE_CTX_FLAGS_READONLY) FAIL("Read-only flag was set");
+    if (flags & REDISMODULE_CTX_FLAGS_CLUSTER) FAIL("Cluster flag was set");
+
+    /* Disable maxmemory and test the flag. (it is implicitly set in 32bit builds. */
+    RedisModule_Call(ctx, "config", "ccc", "set", "maxmemory", "0");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (flags & REDISMODULE_CTX_FLAGS_MAXMEMORY) FAIL("Maxmemory flag was set");
+
+    /* Enable maxmemory and test the flag. */
+    RedisModule_Call(ctx, "config", "ccc", "set", "maxmemory", "100000000");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (!(flags & REDISMODULE_CTX_FLAGS_MAXMEMORY))
+        FAIL("Maxmemory flag was not set after config set");
+
+    if (flags & REDISMODULE_CTX_FLAGS_EVICT) FAIL("Eviction flag was set");
+    RedisModule_Call(ctx, "config", "ccc", "set", "maxmemory-policy", "allkeys-lru");
+    flags = RedisModule_GetContextFlags(ctx);
+    if (!(flags & REDISMODULE_CTX_FLAGS_EVICT)) FAIL("Eviction flag was not set after config set");
+
+end:
+    /* Revert config changes */
+    RedisModule_Call(ctx, "config", "ccc", "set", "appendonly", "no");
+    RedisModule_Call(ctx, "config", "ccc", "set", "save", "");
+    RedisModule_Call(ctx, "config", "ccc", "set", "maxmemory", "0");
+    RedisModule_Call(ctx, "config", "ccc", "set", "maxmemory-policy", "noeviction");
+
+    if (!ok) {
+        RedisModule_Log(ctx, "warning", "Failed CTXFLAGS Test. Reason: %s", errString);
+        return RedisModule_ReplyWithSimpleString(ctx, "ERR");
+    }
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+/* ----------------------------- Test framework ----------------------------- */
+
+/* Return 1 if the reply matches the specified string, otherwise log errors
+ * in the server log and return 0. */
+int TestAssertErrorReply(RedisModuleCtx *ctx, RedisModuleCallReply *reply, char *str, size_t len) {
+    RedisModuleString *mystr, *expected;
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_ERROR) {
+        return 0;
+    }
+
+    mystr = RedisModule_CreateStringFromCallReply(reply);
+    expected = RedisModule_CreateString(ctx,str,len);
+    if (RedisModule_StringCompare(mystr,expected) != 0) {
+        const char *mystr_ptr = RedisModule_StringPtrLen(mystr,NULL);
+        const char *expected_ptr = RedisModule_StringPtrLen(expected,NULL);
+        RedisModule_Log(ctx,"warning",
+            "Unexpected Error reply reply '%s' (instead of '%s')",
+            mystr_ptr, expected_ptr);
+        return 0;
+    }
+    return 1;
+}
+
+int TestAssertStringReply(RedisModuleCtx *ctx, RedisModuleCallReply *reply, char *str, size_t len) {
+    RedisModuleString *mystr, *expected;
+
+    if (RedisModule_CallReplyType(reply) == REDISMODULE_REPLY_ERROR) {
+        RedisModule_Log(ctx,"warning","Test error reply: %s",
+            RedisModule_CallReplyStringPtr(reply, NULL));
+        return 0;
+    } else if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_STRING) {
+        RedisModule_Log(ctx,"warning","Unexpected reply type %d",
+            RedisModule_CallReplyType(reply));
+        return 0;
+    }
+    mystr = RedisModule_CreateStringFromCallReply(reply);
+    expected = RedisModule_CreateString(ctx,str,len);
+    if (RedisModule_StringCompare(mystr,expected) != 0) {
+        const char *mystr_ptr = RedisModule_StringPtrLen(mystr,NULL);
+        const char *expected_ptr = RedisModule_StringPtrLen(expected,NULL);
+        RedisModule_Log(ctx,"warning",
+            "Unexpected string reply '%s' (instead of '%s')",
+            mystr_ptr, expected_ptr);
+        return 0;
+    }
+    return 1;
+}
+
+/* Return 1 if the reply matches the specified integer, otherwise log errors
+ * in the server log and return 0. */
+int TestAssertIntegerReply(RedisModuleCtx *ctx, RedisModuleCallReply *reply, long long expected) {
+    if (RedisModule_CallReplyType(reply) == REDISMODULE_REPLY_ERROR) {
+        RedisModule_Log(ctx,"warning","Test error reply: %s",
+            RedisModule_CallReplyStringPtr(reply, NULL));
+        return 0;
+    } else if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_INTEGER) {
+        RedisModule_Log(ctx,"warning","Unexpected reply type %d",
+            RedisModule_CallReplyType(reply));
+        return 0;
+    }
+    long long val = RedisModule_CallReplyInteger(reply);
+    if (val != expected) {
+        RedisModule_Log(ctx,"warning",
+            "Unexpected integer reply '%lld' (instead of '%lld')",
+            val, expected);
+        return 0;
+    }
+    return 1;
+}
+
+#define T(name,...) \
+    do { \
+        RedisModule_Log(ctx,"warning","Testing %s", name); \
+        reply = RedisModule_Call(ctx,name,__VA_ARGS__); \
+    } while (0)
+
+/* TEST.BASICS -- Run all the tests.
+ * Note: it is useful to run these tests from the module rather than TCL
+ * since it's easier to check the reply types like that (make a distinction
+ * between 0 and "0", etc. */
+int TestBasics(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleCallReply *reply;
+
+    /* Make sure the DB is empty before to proceed. */
+    T("dbsize","");
+    if (!TestAssertIntegerReply(ctx,reply,0)) goto fail;
+
+    T("ping","");
+    if (!TestAssertStringReply(ctx,reply,"PONG",4)) goto fail;
+
+    T("test.call","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callresp3map","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callresp3set","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callresp3double","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callresp3bool","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callresp3null","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callreplywithnestedreply","");
+    if (!TestAssertStringReply(ctx,reply,"test",4)) goto fail;
+
+    T("test.callreplywithbignumberreply","");
+    if (!TestAssertStringReply(ctx,reply,"1234567999999999999999999999999999999",37)) goto fail;
+
+    T("test.callreplywithverbatimstringreply","");
+    if (!TestAssertStringReply(ctx,reply,"txt:This is a verbatim\nstring",29)) goto fail;
+
+    T("test.ctxflags","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.string.append","");
+    if (!TestAssertStringReply(ctx,reply,"foobar",6)) goto fail;
+
+    T("test.string.truncate","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.unlink","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.nestedcallreplyarray","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.string.append.am","");
+    if (!TestAssertStringReply(ctx,reply,"foobar",6)) goto fail;
+    
+    T("test.string.trim","");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.string.printf", "cc", "foo", "bar");
+    if (!TestAssertStringReply(ctx,reply,"Got 3 args. argv[1]: foo, argv[2]: bar",38)) goto fail;
+
+    T("test.notify", "");
+    if (!TestAssertStringReply(ctx,reply,"OK",2)) goto fail;
+
+    T("test.callreplywitharrayreply", "");
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_ARRAY) goto fail;
+    if (RedisModule_CallReplyLength(reply) != 2) goto fail;
+    if (!TestAssertStringReply(ctx,RedisModule_CallReplyArrayElement(reply, 0),"test",4)) goto fail;
+    if (!TestAssertStringReply(ctx,RedisModule_CallReplyArrayElement(reply, 1),"1234",4)) goto fail;
+
+    T("foo", "E");
+    if (!TestAssertErrorReply(ctx,reply,"ERR unknown command 'foo', with args beginning with: ",53)) goto fail;
+
+    T("set", "Ec", "x");
+    if (!TestAssertErrorReply(ctx,reply,"ERR wrong number of arguments for 'set' command",47)) goto fail;
+
+    T("shutdown", "SE");
+    if (!TestAssertErrorReply(ctx,reply,"ERR command 'shutdown' is not allowed on script mode",52)) goto fail;
+
+    T("set", "WEcc", "x", "1");
+    if (!TestAssertErrorReply(ctx,reply,"ERR Write command 'set' was called while write is not allowed.",62)) goto fail;
+
+    RedisModule_ReplyWithSimpleString(ctx,"ALL TESTS PASSED");
+    return REDISMODULE_OK;
+
+fail:
+    RedisModule_ReplyWithSimpleString(ctx,
+        "SOME TEST DID NOT PASS! Check server logs");
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"test",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* Perform RM_Call inside the RedisModule_OnLoad
+     * to verify that it works as expected without crashing.
+     * The tests will verify it on different configurations
+     * options (cluster/no cluster). A simple ping command
+     * is enough for this test. */
+    RedisModuleCallReply *reply = RedisModule_Call(ctx, "ping", "");
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_STRING) {
+        RedisModule_FreeCallReply(reply);
+        return REDISMODULE_ERR;
+    }
+    size_t len;
+    const char *reply_str = RedisModule_CallReplyStringPtr(reply, &len);
+    if (len != 4) {
+        RedisModule_FreeCallReply(reply);
+        return REDISMODULE_ERR;
+    }
+    if (memcmp(reply_str, "PONG", 4) != 0) {
+        RedisModule_FreeCallReply(reply);
+        return REDISMODULE_ERR;
+    }
+    RedisModule_FreeCallReply(reply);
+
+    if (RedisModule_CreateCommand(ctx,"test.call",
+        TestCall,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3map",
+        TestCallResp3Map,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3attribute",
+        TestCallResp3Attribute,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3set",
+        TestCallResp3Set,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3double",
+        TestCallResp3Double,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3bool",
+        TestCallResp3Bool,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callresp3null",
+        TestCallResp3Null,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callreplywitharrayreply",
+        TestCallReplyWithArrayReply,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callreplywithnestedreply",
+        TestCallReplyWithNestedReply,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callreplywithbignumberreply",
+        TestCallResp3BigNumber,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.callreplywithverbatimstringreply",
+        TestCallResp3Verbatim,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.string.append",
+        TestStringAppend,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.string.trim",
+        TestTrimString,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.string.append.am",
+        TestStringAppendAM,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.string.truncate",
+        TestStringTruncate,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.string.printf",
+        TestStringPrintf,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.ctxflags",
+        TestCtxFlags,"readonly",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.unlink",
+        TestUnlink,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.nestedcallreplyarray",
+        TestNestedCallReplyArrayElement,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.basics",
+        TestBasics,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* the following commands are used by an external test and should not be added to TestBasics */
+    if (RedisModule_CreateCommand(ctx,"test.rmcallautomode",
+        TestCallRespAutoMode,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.getresp",
+        TestGetResp,"readonly",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModule_SubscribeToKeyspaceEvents(ctx,
+                                            REDISMODULE_NOTIFY_HASH |
+                                            REDISMODULE_NOTIFY_SET |
+                                            REDISMODULE_NOTIFY_STRING |
+                                            REDISMODULE_NOTIFY_KEY_MISS,
+                                        NotifyCallback);
+    if (RedisModule_CreateCommand(ctx,"test.notify",
+        TestNotifications,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/blockedclient.c b/tests/modules/blockedclient.c
new file mode 100644
index 0000000..92060fd
--- /dev/null
+++ b/tests/modules/blockedclient.c
@@ -0,0 +1,712 @@
+/* define macros for having usleep */
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE
+#include <unistd.h>
+
+#include "redismodule.h"
+#include <assert.h>
+#include <stdio.h>
+#include <pthread.h>
+#include <strings.h>
+
+#define UNUSED(V) ((void) V)
+
+/* used to test processing events during slow bg operation */
+static volatile int g_slow_bg_operation = 0;
+static volatile int g_is_in_slow_bg_operation = 0;
+
+void *sub_worker(void *arg) {
+    // Get Redis module context
+    RedisModuleCtx *ctx = (RedisModuleCtx *)arg;
+
+    // Try acquiring GIL
+    int res = RedisModule_ThreadSafeContextTryLock(ctx);
+
+    // GIL is already taken by the calling thread expecting to fail.
+    assert(res != REDISMODULE_OK);
+
+    return NULL;
+}
+
+void *worker(void *arg) {
+    // Retrieve blocked client
+    RedisModuleBlockedClient *bc = (RedisModuleBlockedClient *)arg;
+
+    // Get Redis module context
+    RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(bc);
+
+    // Acquire GIL
+    RedisModule_ThreadSafeContextLock(ctx);
+
+    // Create another thread which will try to acquire the GIL
+    pthread_t tid;
+    int res = pthread_create(&tid, NULL, sub_worker, ctx);
+    assert(res == 0);
+
+    // Wait for thread
+    pthread_join(tid, NULL);
+
+    // Release GIL
+    RedisModule_ThreadSafeContextUnlock(ctx);
+
+    // Reply to client
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+    // Unblock client
+    RedisModule_UnblockClient(bc, NULL);
+
+    // Free the Redis module context
+    RedisModule_FreeThreadSafeContext(ctx);
+
+    return NULL;
+}
+
+int acquire_gil(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    UNUSED(argv);
+    UNUSED(argc);
+
+    int flags = RedisModule_GetContextFlags(ctx);
+    int allFlags = RedisModule_GetContextFlagsAll();
+    if ((allFlags & REDISMODULE_CTX_FLAGS_MULTI) &&
+        (flags & REDISMODULE_CTX_FLAGS_MULTI)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not supported inside multi");
+        return REDISMODULE_OK;
+    }
+
+    if ((allFlags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING) &&
+        (flags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not allowed");
+        return REDISMODULE_OK;
+    }
+
+    /* This command handler tries to acquire the GIL twice
+     * once in the worker thread using "RedisModule_ThreadSafeContextLock"
+     * second in the sub-worker thread
+     * using "RedisModule_ThreadSafeContextTryLock"
+     * as the GIL is already locked. */
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+
+    pthread_t tid;
+    int res = pthread_create(&tid, NULL, worker, bc);
+    assert(res == 0);
+
+    return REDISMODULE_OK;
+}
+
+typedef struct {
+    RedisModuleString **argv;
+    int argc;
+    RedisModuleBlockedClient *bc;
+} bg_call_data;
+
+void *bg_call_worker(void *arg) {
+    bg_call_data *bg = arg;
+
+    // Get Redis module context
+    RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(bg->bc);
+
+    // Acquire GIL
+    RedisModule_ThreadSafeContextLock(ctx);
+
+    // Test slow operation yielding
+    if (g_slow_bg_operation) {
+        g_is_in_slow_bg_operation = 1;
+        while (g_slow_bg_operation) {
+            RedisModule_Yield(ctx, REDISMODULE_YIELD_FLAG_CLIENTS, "Slow module operation");
+            usleep(1000);
+        }
+        g_is_in_slow_bg_operation = 0;
+    }
+
+    // Call the command
+    const char *module_cmd = RedisModule_StringPtrLen(bg->argv[0], NULL);
+    int cmd_pos = 1;
+    RedisModuleString *format_redis_str = RedisModule_CreateString(NULL, "v", 1);
+    if (!strcasecmp(module_cmd, "do_bg_rm_call_format")) {
+        cmd_pos = 2;
+        size_t format_len;
+        const char *format = RedisModule_StringPtrLen(bg->argv[1], &format_len);
+        RedisModule_StringAppendBuffer(NULL, format_redis_str, format, format_len);
+        RedisModule_StringAppendBuffer(NULL, format_redis_str, "E", 1);
+    }
+    const char *format = RedisModule_StringPtrLen(format_redis_str, NULL);
+    const char *cmd = RedisModule_StringPtrLen(bg->argv[cmd_pos], NULL);
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, cmd, format, bg->argv + cmd_pos + 1, bg->argc - cmd_pos - 1);
+    RedisModule_FreeString(NULL, format_redis_str);
+
+    // Release GIL
+    RedisModule_ThreadSafeContextUnlock(ctx);
+
+    // Reply to client
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    // Unblock client
+    RedisModule_UnblockClient(bg->bc, NULL);
+
+    /* Free the arguments */
+    for (int i=0; i<bg->argc; i++)
+        RedisModule_FreeString(ctx, bg->argv[i]);
+    RedisModule_Free(bg->argv);
+    RedisModule_Free(bg);
+
+    // Free the Redis module context
+    RedisModule_FreeThreadSafeContext(ctx);
+
+    return NULL;
+}
+
+int do_bg_rm_call(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    UNUSED(argv);
+    UNUSED(argc);
+
+    /* Make sure we're not trying to block a client when we shouldn't */
+    int flags = RedisModule_GetContextFlags(ctx);
+    int allFlags = RedisModule_GetContextFlagsAll();
+    if ((allFlags & REDISMODULE_CTX_FLAGS_MULTI) &&
+        (flags & REDISMODULE_CTX_FLAGS_MULTI)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not supported inside multi");
+        return REDISMODULE_OK;
+    }
+    if ((allFlags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING) &&
+        (flags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not allowed");
+        return REDISMODULE_OK;
+    }
+
+    /* Make a copy of the arguments and pass them to the thread. */
+    bg_call_data *bg = RedisModule_Alloc(sizeof(bg_call_data));
+    bg->argv = RedisModule_Alloc(sizeof(RedisModuleString*)*argc);
+    bg->argc = argc;
+    for (int i=0; i<argc; i++)
+        bg->argv[i] = RedisModule_HoldString(ctx, argv[i]);
+
+    /* Block the client */
+    bg->bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+
+    /* Start a thread to handle the request */
+    pthread_t tid;
+    int res = pthread_create(&tid, NULL, bg_call_worker, bg);
+    assert(res == 0);
+
+    return REDISMODULE_OK;
+}
+
+int do_rm_call(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "Ev", argv + 2, argc - 2);
+    if(!rep){
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    }else{
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+static void rm_call_async_send_reply(RedisModuleCtx *ctx, RedisModuleCallReply *reply) {
+    RedisModule_ReplyWithCallReply(ctx, reply);
+    RedisModule_FreeCallReply(reply);
+}
+
+/* Called when the command that was blocked on 'RM_Call' gets unblocked
+ * and send the reply to the blocked client. */
+static void rm_call_async_on_unblocked(RedisModuleCtx *ctx, RedisModuleCallReply *reply, void *private_data) {
+    UNUSED(ctx);
+    RedisModuleBlockedClient *bc = private_data;
+    RedisModuleCtx *bctx = RedisModule_GetThreadSafeContext(bc);
+    rm_call_async_send_reply(bctx, reply);
+    RedisModule_FreeThreadSafeContext(bctx);
+    RedisModule_UnblockClient(bc, RedisModule_BlockClientGetPrivateData(bc));
+}
+
+int do_rm_call_async_fire_and_forget(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "!KEv", argv + 2, argc - 2);
+
+    if(RedisModule_CallReplyType(rep) != REDISMODULE_REPLY_PROMISE) {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+    } else {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked");
+    }
+    RedisModule_FreeCallReply(rep);
+
+    return REDISMODULE_OK;
+}
+
+static void do_rm_call_async_free_pd(RedisModuleCtx * ctx, void *pd) {
+    UNUSED(ctx);
+    RedisModule_FreeCallReply(pd);
+}
+
+static void do_rm_call_async_disconnect(RedisModuleCtx *ctx, struct RedisModuleBlockedClient *bc) {
+    UNUSED(ctx);
+    RedisModuleCallReply* rep = RedisModule_BlockClientGetPrivateData(bc);
+    RedisModule_CallReplyPromiseAbort(rep, NULL);
+    RedisModule_FreeCallReply(rep);
+    RedisModule_AbortBlock(bc);
+}
+
+/*
+ * Callback for do_rm_call_async / do_rm_call_async_script_mode
+ * Gets the command to invoke as the first argument to the command and runs it,
+ * passing the rest of the arguments to the command invocation.
+ * If the command got blocked, blocks the client and unblock it when the command gets unblocked,
+ * this allows check the K (allow blocking) argument to RM_Call.
+ */
+int do_rm_call_async(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    size_t format_len = 0;
+    char format[6] = {0};
+
+    if (!(RedisModule_GetContextFlags(ctx) & REDISMODULE_CTX_FLAGS_DENY_BLOCKING)) {
+        /* We are allowed to block the client so we can allow RM_Call to also block us */
+        format[format_len++] = 'K';
+    }
+
+    const char* invoked_cmd = RedisModule_StringPtrLen(argv[0], NULL);
+    if (strcasecmp(invoked_cmd, "do_rm_call_async_script_mode") == 0) {
+        format[format_len++] = 'S';
+    }
+
+    format[format_len++] = 'E';
+    format[format_len++] = 'v';
+    if (strcasecmp(invoked_cmd, "do_rm_call_async_no_replicate") != 0) {
+        /* Notice, without the '!' flag we will have inconsistency between master and replica.
+         * This is used only to check '!' flag correctness on blocked commands. */
+        format[format_len++] = '!';
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, format, argv + 2, argc - 2);
+
+    if(RedisModule_CallReplyType(rep) != REDISMODULE_REPLY_PROMISE) {
+        rm_call_async_send_reply(ctx, rep);
+    } else {
+        RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, do_rm_call_async_free_pd, 0);
+        RedisModule_SetDisconnectCallback(bc, do_rm_call_async_disconnect);
+        RedisModule_BlockClientSetPrivateData(bc, rep);
+        RedisModule_CallReplyPromiseSetUnblockHandler(rep, rm_call_async_on_unblocked, bc);
+    }
+
+    return REDISMODULE_OK;
+}
+
+typedef struct ThreadedAsyncRMCallCtx{
+    RedisModuleBlockedClient *bc;
+    RedisModuleCallReply *reply;
+} ThreadedAsyncRMCallCtx;
+
+void *send_async_reply(void *arg) {
+    ThreadedAsyncRMCallCtx *ta_rm_call_ctx = arg;
+    rm_call_async_on_unblocked(NULL, ta_rm_call_ctx->reply, ta_rm_call_ctx->bc);
+    RedisModule_Free(ta_rm_call_ctx);
+    return NULL;
+}
+
+/* Called when the command that was blocked on 'RM_Call' gets unblocked
+ * and schedule a thread to send the reply to the blocked client. */
+static void rm_call_async_reply_on_thread(RedisModuleCtx *ctx, RedisModuleCallReply *reply, void *private_data) {
+    UNUSED(ctx);
+    ThreadedAsyncRMCallCtx *ta_rm_call_ctx = RedisModule_Alloc(sizeof(*ta_rm_call_ctx));
+    ta_rm_call_ctx->bc = private_data;
+    ta_rm_call_ctx->reply = reply;
+    pthread_t tid;
+    int res = pthread_create(&tid, NULL, send_async_reply, ta_rm_call_ctx);
+    assert(res == 0);
+}
+
+/*
+ * Callback for do_rm_call_async_on_thread.
+ * Gets the command to invoke as the first argument to the command and runs it,
+ * passing the rest of the arguments to the command invocation.
+ * If the command got blocked, blocks the client and unblock on a background thread.
+ * this allows check the K (allow blocking) argument to RM_Call, and make sure that the reply
+ * that passes to unblock handler is owned by the handler and are not attached to any
+ * context that might be freed after the callback ends.
+ */
+int do_rm_call_async_on_thread(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "KEv", argv + 2, argc - 2);
+
+    if(RedisModule_CallReplyType(rep) != REDISMODULE_REPLY_PROMISE) {
+        rm_call_async_send_reply(ctx, rep);
+    } else {
+        RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+        RedisModule_CallReplyPromiseSetUnblockHandler(rep, rm_call_async_reply_on_thread, bc);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+/* Private data for wait_and_do_rm_call_async that holds information about:
+ * 1. the block client, to unblock when done.
+ * 2. the arguments, contains the command to run using RM_Call */
+typedef struct WaitAndDoRMCallCtx {
+    RedisModuleBlockedClient *bc;
+    RedisModuleString **argv;
+    int argc;
+} WaitAndDoRMCallCtx;
+
+/*
+ * This callback will be called when the 'wait' command invoke on 'wait_and_do_rm_call_async' will finish.
+ * This callback will continue the execution flow just like 'do_rm_call_async' command.
+ */
+static void wait_and_do_rm_call_async_on_unblocked(RedisModuleCtx *ctx, RedisModuleCallReply *reply, void *private_data) {
+    WaitAndDoRMCallCtx *wctx = private_data;
+    if (RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_INTEGER) {
+        goto done;
+    }
+
+    if (RedisModule_CallReplyInteger(reply) != 1) {
+        goto done;
+    }
+
+    RedisModule_FreeCallReply(reply);
+    reply = NULL;
+
+    const char* cmd = RedisModule_StringPtrLen(wctx->argv[0], NULL);
+    reply = RedisModule_Call(ctx, cmd, "!EKv", wctx->argv + 1, wctx->argc - 1);
+
+done:
+    if(RedisModule_CallReplyType(reply) != REDISMODULE_REPLY_PROMISE) {
+        RedisModuleCtx *bctx = RedisModule_GetThreadSafeContext(wctx->bc);
+        rm_call_async_send_reply(bctx, reply);
+        RedisModule_FreeThreadSafeContext(bctx);
+        RedisModule_UnblockClient(wctx->bc, NULL);
+    } else {
+        RedisModule_CallReplyPromiseSetUnblockHandler(reply, rm_call_async_on_unblocked, wctx->bc);
+        RedisModule_FreeCallReply(reply);
+    }
+    for (int i = 0 ; i < wctx->argc ; ++i) {
+        RedisModule_FreeString(NULL, wctx->argv[i]);
+    }
+    RedisModule_Free(wctx->argv);
+    RedisModule_Free(wctx);
+}
+
+/*
+ * Callback for wait_and_do_rm_call
+ * Gets the command to invoke as the first argument, runs 'wait'
+ * command (using the K flag to RM_Call). Once the wait finished, runs the
+ * command that was given (just like 'do_rm_call_async').
+ */
+int wait_and_do_rm_call_async(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    int flags = RedisModule_GetContextFlags(ctx);
+    if (flags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING) {
+        return RedisModule_ReplyWithError(ctx, "Err can not run wait, blocking is not allowed.");
+    }
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "wait", "!EKcc", "1", "0");
+    if(RedisModule_CallReplyType(rep) != REDISMODULE_REPLY_PROMISE) {
+        rm_call_async_send_reply(ctx, rep);
+    } else {
+        RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+        WaitAndDoRMCallCtx *wctx = RedisModule_Alloc(sizeof(*wctx));
+        *wctx = (WaitAndDoRMCallCtx){
+                .bc = bc,
+                .argv = RedisModule_Alloc((argc - 1) * sizeof(RedisModuleString*)),
+                .argc = argc - 1,
+        };
+
+        for (int i = 1 ; i < argc ; ++i) {
+            wctx->argv[i - 1] = RedisModule_HoldString(NULL, argv[i]);
+        }
+        RedisModule_CallReplyPromiseSetUnblockHandler(rep, wait_and_do_rm_call_async_on_unblocked, wctx);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+static void blpop_and_set_multiple_keys_on_unblocked(RedisModuleCtx *ctx, RedisModuleCallReply *reply, void *private_data) {
+    /* ignore the reply */
+    RedisModule_FreeCallReply(reply);
+    WaitAndDoRMCallCtx *wctx = private_data;
+    for (int i = 0 ; i < wctx->argc ; i += 2) {
+        RedisModuleCallReply* rep = RedisModule_Call(ctx, "set", "!ss", wctx->argv[i], wctx->argv[i + 1]);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    RedisModuleCtx *bctx = RedisModule_GetThreadSafeContext(wctx->bc);
+    RedisModule_ReplyWithSimpleString(bctx, "OK");
+    RedisModule_FreeThreadSafeContext(bctx);
+    RedisModule_UnblockClient(wctx->bc, NULL);
+
+    for (int i = 0 ; i < wctx->argc ; ++i) {
+        RedisModule_FreeString(NULL, wctx->argv[i]);
+    }
+    RedisModule_Free(wctx->argv);
+    RedisModule_Free(wctx);
+
+}
+
+/*
+ * Performs a blpop command on a given list and when unblocked set multiple string keys.
+ * This command allows checking that the unblock callback is performed as a unit
+ * and its effect are replicated to the replica and AOF wrapped with multi exec.
+ */
+int blpop_and_set_multiple_keys(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if(argc < 2 || argc % 2 != 0){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    int flags = RedisModule_GetContextFlags(ctx);
+    if (flags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING) {
+        return RedisModule_ReplyWithError(ctx, "Err can not run wait, blocking is not allowed.");
+    }
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "blpop", "!EKsc", argv[1], "0");
+    if(RedisModule_CallReplyType(rep) != REDISMODULE_REPLY_PROMISE) {
+        rm_call_async_send_reply(ctx, rep);
+    } else {
+        RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+        WaitAndDoRMCallCtx *wctx = RedisModule_Alloc(sizeof(*wctx));
+        *wctx = (WaitAndDoRMCallCtx){
+                .bc = bc,
+                .argv = RedisModule_Alloc((argc - 2) * sizeof(RedisModuleString*)),
+                .argc = argc - 2,
+        };
+
+        for (int i = 0 ; i < argc - 2 ; ++i) {
+            wctx->argv[i] = RedisModule_HoldString(NULL, argv[i + 2]);
+        }
+        RedisModule_CallReplyPromiseSetUnblockHandler(rep, blpop_and_set_multiple_keys_on_unblocked, wctx);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+/* simulate a blocked client replying to a thread safe context without creating a thread */
+int do_fake_bg_true(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+    RedisModuleCtx *bctx = RedisModule_GetThreadSafeContext(bc);
+
+    RedisModule_ReplyWithBool(bctx, 1);
+
+    RedisModule_FreeThreadSafeContext(bctx);
+    RedisModule_UnblockClient(bc, NULL);
+
+    return REDISMODULE_OK;
+}
+
+
+/* this flag is used to work with busy commands, that might take a while
+ * and ability to stop the busy work with a different command*/
+static volatile int abort_flag = 0;
+
+int slow_fg_command(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    long long block_time = 0;
+    if (RedisModule_StringToLongLong(argv[1], &block_time) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+
+    uint64_t start_time = RedisModule_MonotonicMicroseconds();
+    /* when not blocking indefinitely, we don't process client commands in this test. */
+    int yield_flags = block_time? REDISMODULE_YIELD_FLAG_NONE: REDISMODULE_YIELD_FLAG_CLIENTS;
+    while (!abort_flag) {
+        RedisModule_Yield(ctx, yield_flags, "Slow module operation");
+        usleep(1000);
+        if (block_time && RedisModule_MonotonicMicroseconds() - start_time > (uint64_t)block_time)
+            break;
+    }
+
+    abort_flag = 0;
+    RedisModule_ReplyWithLongLong(ctx, 1);
+    return REDISMODULE_OK;
+}
+
+int stop_slow_fg_command(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    abort_flag = 1;
+    RedisModule_ReplyWithLongLong(ctx, 1);
+    return REDISMODULE_OK;
+}
+
+/* used to enable or disable slow operation in do_bg_rm_call */
+static int set_slow_bg_operation(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    long long ll;
+    if (RedisModule_StringToLongLong(argv[1], &ll) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+    g_slow_bg_operation = ll;
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* used to test if we reached the slow operation in do_bg_rm_call */
+static int is_in_slow_bg_operation(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    if (argc != 1) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithLongLong(ctx, g_is_in_slow_bg_operation);
+    return REDISMODULE_OK;
+}
+
+static void timer_callback(RedisModuleCtx *ctx, void *data)
+{
+    UNUSED(ctx);
+
+    RedisModuleBlockedClient *bc = data;
+
+    // Get Redis module context
+    RedisModuleCtx *reply_ctx = RedisModule_GetThreadSafeContext(bc);
+
+    // Reply to client
+    RedisModule_ReplyWithSimpleString(reply_ctx, "OK");
+
+    // Unblock client
+    RedisModule_UnblockClient(bc, NULL);
+
+    // Free the Redis module context
+    RedisModule_FreeThreadSafeContext(reply_ctx);
+}
+
+int unblock_by_timer(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    long long period;
+    if (RedisModule_StringToLongLong(argv[1],&period) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid period");
+
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+    RedisModule_CreateTimer(ctx, period, timer_callback, bc);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "blockedclient", 1, REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "acquire_gil", acquire_gil, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call", do_rm_call,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call_async", do_rm_call_async,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call_async_on_thread", do_rm_call_async_on_thread,
+                                      "write", 0, 0, 0) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call_async_script_mode", do_rm_call_async,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call_async_no_replicate", do_rm_call_async,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_rm_call_fire_and_forget", do_rm_call_async_fire_and_forget,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "wait_and_do_rm_call", wait_and_do_rm_call_async,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blpop_and_set_multiple_keys", blpop_and_set_multiple_keys,
+                                      "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_bg_rm_call", do_bg_rm_call, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_bg_rm_call_format", do_bg_rm_call, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "do_fake_bg_true", do_fake_bg_true, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "slow_fg_command", slow_fg_command,"", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "stop_slow_fg_command", stop_slow_fg_command,"allow-busy", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "set_slow_bg_operation", set_slow_bg_operation, "allow-busy", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "is_in_slow_bg_operation", is_in_slow_bg_operation, "allow-busy", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "unblock_by_timer", unblock_by_timer, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/blockonbackground.c b/tests/modules/blockonbackground.c
new file mode 100644
index 0000000..2e3b1a5
--- /dev/null
+++ b/tests/modules/blockonbackground.c
@@ -0,0 +1,295 @@
+#define _XOPEN_SOURCE 700
+#include "redismodule.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <time.h>
+
+#define UNUSED(x) (void)(x)
+
+/* Reply callback for blocking command BLOCK.DEBUG */
+int HelloBlock_Reply(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    int *myint = RedisModule_GetBlockedClientPrivateData(ctx);
+    return RedisModule_ReplyWithLongLong(ctx,*myint);
+}
+
+/* Timeout callback for blocking command BLOCK.DEBUG */
+int HelloBlock_Timeout(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModuleBlockedClient *bc = RedisModule_GetBlockedClientHandle(ctx);
+    RedisModule_BlockedClientMeasureTimeEnd(bc);
+    return RedisModule_ReplyWithSimpleString(ctx,"Request timedout");
+}
+
+/* Private data freeing callback for BLOCK.DEBUG command. */
+void HelloBlock_FreeData(RedisModuleCtx *ctx, void *privdata) {
+    UNUSED(ctx);
+    RedisModule_Free(privdata);
+}
+
+/* Private data freeing callback for BLOCK.BLOCK command. */
+void HelloBlock_FreeStringData(RedisModuleCtx *ctx, void *privdata) {
+    RedisModule_FreeString(ctx, (RedisModuleString*)privdata);
+}
+
+/* The thread entry point that actually executes the blocking part
+ * of the command BLOCK.DEBUG. */
+void *BlockDebug_ThreadMain(void *arg) {
+    void **targ = arg;
+    RedisModuleBlockedClient *bc = targ[0];
+    long long delay = (unsigned long)targ[1];
+    long long enable_time_track = (unsigned long)targ[2];
+    if (enable_time_track)
+        RedisModule_BlockedClientMeasureTimeStart(bc);
+    RedisModule_Free(targ);
+
+    struct timespec ts;
+    ts.tv_sec = delay / 1000;
+    ts.tv_nsec = (delay % 1000) * 1000000;
+    nanosleep(&ts, NULL);
+    int *r = RedisModule_Alloc(sizeof(int));
+    *r = rand();
+    if (enable_time_track)
+        RedisModule_BlockedClientMeasureTimeEnd(bc);
+    RedisModule_UnblockClient(bc,r);
+    return NULL;
+}
+
+/* The thread entry point that actually executes the blocking part
+ * of the command BLOCK.DOUBLE_DEBUG. */
+void *DoubleBlock_ThreadMain(void *arg) {
+    void **targ = arg;
+    RedisModuleBlockedClient *bc = targ[0];
+    long long delay = (unsigned long)targ[1];
+    RedisModule_BlockedClientMeasureTimeStart(bc);
+    RedisModule_Free(targ);
+    struct timespec ts;
+    ts.tv_sec = delay / 1000;
+    ts.tv_nsec = (delay % 1000) * 1000000;
+    nanosleep(&ts, NULL);
+    int *r = RedisModule_Alloc(sizeof(int));
+    *r = rand();
+    RedisModule_BlockedClientMeasureTimeEnd(bc);
+    /* call again RedisModule_BlockedClientMeasureTimeStart() and
+     * RedisModule_BlockedClientMeasureTimeEnd and ensure that the
+     * total execution time is 2x the delay. */
+    RedisModule_BlockedClientMeasureTimeStart(bc);
+    nanosleep(&ts, NULL);
+    RedisModule_BlockedClientMeasureTimeEnd(bc);
+
+    RedisModule_UnblockClient(bc,r);
+    return NULL;
+}
+
+void HelloBlock_Disconnected(RedisModuleCtx *ctx, RedisModuleBlockedClient *bc) {
+    RedisModule_Log(ctx,"warning","Blocked client %p disconnected!",
+        (void*)bc);
+}
+
+/* BLOCK.DEBUG <delay_ms> <timeout_ms> -- Block for <count> milliseconds, then reply with
+ * a random number. Timeout is the command timeout, so that you can test
+ * what happens when the delay is greater than the timeout. */
+int HelloBlock_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    long long delay;
+    long long timeout;
+
+    if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid count");
+    }
+
+    if (RedisModule_StringToLongLong(argv[2],&timeout) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid count");
+    }
+
+    pthread_t tid;
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,timeout);
+
+    /* Here we set a disconnection handler, however since this module will
+     * block in sleep() in a thread, there is not much we can do in the
+     * callback, so this is just to show you the API. */
+    RedisModule_SetDisconnectCallback(bc,HelloBlock_Disconnected);
+
+    /* Now that we setup a blocking client, we need to pass the control
+     * to the thread. However we need to pass arguments to the thread:
+     * the delay and a reference to the blocked client handle. */
+    void **targ = RedisModule_Alloc(sizeof(void*)*3);
+    targ[0] = bc;
+    targ[1] = (void*)(unsigned long) delay;
+    // pass 1 as flag to enable time tracking
+    targ[2] = (void*)(unsigned long) 1;
+
+    if (pthread_create(&tid,NULL,BlockDebug_ThreadMain,targ) != 0) {
+        RedisModule_AbortBlock(bc);
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    }
+    return REDISMODULE_OK;
+}
+
+/* BLOCK.DEBUG_NOTRACKING <delay_ms> <timeout_ms> -- Block for <count> milliseconds, then reply with
+ * a random number. Timeout is the command timeout, so that you can test
+ * what happens when the delay is greater than the timeout.
+ * this command does not track background time so the background time should no appear in stats*/
+int HelloBlockNoTracking_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    long long delay;
+    long long timeout;
+
+    if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid count");
+    }
+
+    if (RedisModule_StringToLongLong(argv[2],&timeout) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid count");
+    }
+
+    pthread_t tid;
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,timeout);
+
+    /* Here we set a disconnection handler, however since this module will
+     * block in sleep() in a thread, there is not much we can do in the
+     * callback, so this is just to show you the API. */
+    RedisModule_SetDisconnectCallback(bc,HelloBlock_Disconnected);
+
+    /* Now that we setup a blocking client, we need to pass the control
+     * to the thread. However we need to pass arguments to the thread:
+     * the delay and a reference to the blocked client handle. */
+    void **targ = RedisModule_Alloc(sizeof(void*)*3);
+    targ[0] = bc;
+    targ[1] = (void*)(unsigned long) delay;
+    // pass 0 as flag to enable time tracking
+    targ[2] = (void*)(unsigned long) 0;
+
+    if (pthread_create(&tid,NULL,BlockDebug_ThreadMain,targ) != 0) {
+        RedisModule_AbortBlock(bc);
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    }
+    return REDISMODULE_OK;
+}
+
+/* BLOCK.DOUBLE_DEBUG <delay_ms> -- Block for 2 x <count> milliseconds,
+ * then reply with a random number.
+ * This command is used to test multiple calls to RedisModule_BlockedClientMeasureTimeStart()
+ * and RedisModule_BlockedClientMeasureTimeEnd() within the same execution. */
+int HelloDoubleBlock_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+    long long delay;
+
+    if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid count");
+    }
+
+    pthread_t tid;
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,0);
+
+    /* Now that we setup a blocking client, we need to pass the control
+     * to the thread. However we need to pass arguments to the thread:
+     * the delay and a reference to the blocked client handle. */
+    void **targ = RedisModule_Alloc(sizeof(void*)*2);
+    targ[0] = bc;
+    targ[1] = (void*)(unsigned long) delay;
+
+    if (pthread_create(&tid,NULL,DoubleBlock_ThreadMain,targ) != 0) {
+        RedisModule_AbortBlock(bc);
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    }
+    return REDISMODULE_OK;
+}
+
+RedisModuleBlockedClient *blocked_client = NULL;
+
+/* BLOCK.BLOCK [TIMEOUT] -- Blocks the current client until released
+ * or TIMEOUT seconds. If TIMEOUT is zero, no timeout function is
+ * registered.
+ */
+int Block_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (RedisModule_IsBlockedReplyRequest(ctx)) {
+        RedisModuleString *r = RedisModule_GetBlockedClientPrivateData(ctx);
+        return RedisModule_ReplyWithString(ctx, r);
+    } else if (RedisModule_IsBlockedTimeoutRequest(ctx)) {
+        RedisModule_UnblockClient(blocked_client, NULL); /* Must be called to avoid leaks. */
+        blocked_client = NULL;
+        return RedisModule_ReplyWithSimpleString(ctx, "Timed out");
+    }
+
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+    long long timeout;
+
+    if (RedisModule_StringToLongLong(argv[1], &timeout) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid timeout");
+    }
+    if (blocked_client) {
+        return RedisModule_ReplyWithError(ctx, "ERR another client already blocked");
+    }
+
+    /* Block client. We use this function as both a reply and optional timeout
+     * callback and differentiate the different code flows above.
+     */
+    blocked_client = RedisModule_BlockClient(ctx, Block_RedisCommand,
+            timeout > 0 ? Block_RedisCommand : NULL, HelloBlock_FreeStringData, timeout);
+    return REDISMODULE_OK;
+}
+
+/* BLOCK.IS_BLOCKED -- Returns 1 if we have a blocked client, or 0 otherwise.
+ */
+int IsBlocked_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModule_ReplyWithLongLong(ctx, blocked_client ? 1 : 0);
+    return REDISMODULE_OK;
+}
+
+/* BLOCK.RELEASE [reply] -- Releases the blocked client and produce the specified reply.
+ */
+int Release_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+    if (!blocked_client) {
+        return RedisModule_ReplyWithError(ctx, "ERR No blocked client");
+    }
+
+    RedisModuleString *replystr = argv[1];
+    RedisModule_RetainString(ctx, replystr);
+    RedisModule_UnblockClient(blocked_client, replystr);
+    blocked_client = NULL;
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    if (RedisModule_Init(ctx,"block",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.debug",
+        HelloBlock_RedisCommand,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.double_debug",
+        HelloDoubleBlock_RedisCommand,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.debug_no_track",
+        HelloBlockNoTracking_RedisCommand,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "block.block",
+        Block_RedisCommand, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.is_blocked",
+        IsBlocked_RedisCommand,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"block.release",
+        Release_RedisCommand,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/blockonkeys.c b/tests/modules/blockonkeys.c
new file mode 100644
index 0000000..94bb361
--- /dev/null
+++ b/tests/modules/blockonkeys.c
@@ -0,0 +1,645 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+
+#define UNUSED(V) ((void) V)
+
+#define LIST_SIZE 1024
+
+/* The FSL (Fixed-Size List) data type is a low-budget imitation of the
+ * native Redis list, in order to test list-like commands implemented
+ * by a module.
+ * Examples: FSL.PUSH, FSL.BPOP, etc. */
+
+typedef struct {
+    long long list[LIST_SIZE];
+    long long length;
+} fsl_t; /* Fixed-size list */
+
+static RedisModuleType *fsltype = NULL;
+
+fsl_t *fsl_type_create(void) {
+    fsl_t *o;
+    o = RedisModule_Alloc(sizeof(*o));
+    o->length = 0;
+    return o;
+}
+
+void fsl_type_free(fsl_t *o) {
+    RedisModule_Free(o);
+}
+
+/* ========================== "fsltype" type methods ======================= */
+
+void *fsl_rdb_load(RedisModuleIO *rdb, int encver) {
+    if (encver != 0) {
+        return NULL;
+    }
+    fsl_t *fsl = fsl_type_create();
+    fsl->length = RedisModule_LoadUnsigned(rdb);
+    for (long long i = 0; i < fsl->length; i++)
+        fsl->list[i] = RedisModule_LoadSigned(rdb);
+    return fsl;
+}
+
+void fsl_rdb_save(RedisModuleIO *rdb, void *value) {
+    fsl_t *fsl = value;
+    RedisModule_SaveUnsigned(rdb,fsl->length);
+    for (long long i = 0; i < fsl->length; i++)
+        RedisModule_SaveSigned(rdb, fsl->list[i]);
+}
+
+void fsl_aofrw(RedisModuleIO *aof, RedisModuleString *key, void *value) {
+    fsl_t *fsl = value;
+    for (long long i = 0; i < fsl->length; i++)
+        RedisModule_EmitAOF(aof, "FSL.PUSH","sl", key, fsl->list[i]);
+}
+
+void fsl_free(void *value) {
+    fsl_type_free(value);
+}
+
+/* ========================== helper methods ======================= */
+
+/* Wrapper to the boilerplate code of opening a key, checking its type, etc.
+ * Returns 0 if `keyname` exists in the dataset, but it's of the wrong type (i.e. not FSL) */
+int get_fsl(RedisModuleCtx *ctx, RedisModuleString *keyname, int mode, int create, fsl_t **fsl, int reply_on_failure) {
+    *fsl = NULL;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, keyname, mode);
+
+    if (RedisModule_KeyType(key) != REDISMODULE_KEYTYPE_EMPTY) {
+        /* Key exists */
+        if (RedisModule_ModuleTypeGetType(key) != fsltype) {
+            /* Key is not FSL */
+            RedisModule_CloseKey(key);
+            if (reply_on_failure)
+                RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+            RedisModuleCallReply *reply = RedisModule_Call(ctx, "INCR", "c", "fsl_wrong_type");
+            RedisModule_FreeCallReply(reply);
+            return 0;
+        }
+
+        *fsl = RedisModule_ModuleTypeGetValue(key);
+        if (*fsl && !(*fsl)->length && mode & REDISMODULE_WRITE) {
+            /* Key exists, but it's logically empty */
+            if (create) {
+                create = 0; /* No need to create, key exists in its basic state */
+            } else {
+                RedisModule_DeleteKey(key);
+                *fsl = NULL;
+            }
+        } else {
+            /* Key exists, and has elements in it - no need to create anything */
+            create = 0;
+        }
+    }
+
+    if (create) {
+        *fsl = fsl_type_create();
+        RedisModule_ModuleTypeSetValue(key, fsltype, *fsl);
+    }
+
+    RedisModule_CloseKey(key);
+    return 1;
+}
+
+/* ========================== commands ======================= */
+
+/* FSL.PUSH <key> <int> - Push an integer to the fixed-size list (to the right).
+ * It must be greater than the element in the head of the list. */
+int fsl_push(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3)
+        return RedisModule_WrongArity(ctx);
+
+    long long ele;
+    if (RedisModule_StringToLongLong(argv[2],&ele) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid integer");
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_WRITE, 1, &fsl, 1))
+        return REDISMODULE_OK;
+
+    if (fsl->length == LIST_SIZE)
+        return RedisModule_ReplyWithError(ctx,"ERR list is full");
+
+    if (fsl->length != 0 && fsl->list[fsl->length-1] >= ele)
+        return RedisModule_ReplyWithError(ctx,"ERR new element has to be greater than the head element");
+
+    fsl->list[fsl->length++] = ele;
+    RedisModule_SignalKeyAsReady(ctx, argv[1]);
+
+    RedisModule_ReplicateVerbatim(ctx);
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+typedef struct {
+    RedisModuleString *keyname;
+    long long ele;
+} timer_data_t;
+
+static void timer_callback(RedisModuleCtx *ctx, void *data)
+{
+    timer_data_t *td = data;
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, td->keyname, REDISMODULE_WRITE, 1, &fsl, 1))
+        return;
+
+    if (fsl->length == LIST_SIZE)
+        return; /* list is full */
+
+    if (fsl->length != 0 && fsl->list[fsl->length-1] >= td->ele)
+        return; /* new element has to be greater than the head element */
+
+    fsl->list[fsl->length++] = td->ele;
+    RedisModule_SignalKeyAsReady(ctx, td->keyname);
+
+    RedisModule_Replicate(ctx, "FSL.PUSH", "sl", td->keyname, td->ele);
+
+    RedisModule_FreeString(ctx, td->keyname);
+    RedisModule_Free(td);
+}
+
+/* FSL.PUSHTIMER <key> <int> <period-in-ms> - Push the number 9000 to the fixed-size list (to the right).
+ * It must be greater than the element in the head of the list. */
+int fsl_pushtimer(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 4)
+        return RedisModule_WrongArity(ctx);
+
+    long long ele;
+    if (RedisModule_StringToLongLong(argv[2],&ele) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid integer");
+
+    long long period;
+    if (RedisModule_StringToLongLong(argv[3],&period) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid period");
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_WRITE, 1, &fsl, 1))
+        return REDISMODULE_OK;
+
+    if (fsl->length == LIST_SIZE)
+        return RedisModule_ReplyWithError(ctx,"ERR list is full");
+
+    timer_data_t *td = RedisModule_Alloc(sizeof(*td));
+    td->keyname = argv[1];
+    RedisModule_RetainString(ctx, td->keyname);
+    td->ele = ele;
+
+    RedisModuleTimerID id = RedisModule_CreateTimer(ctx, period, timer_callback, td);
+    RedisModule_ReplyWithLongLong(ctx, id);
+
+    return REDISMODULE_OK;
+}
+
+int bpop_reply_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleString *keyname = RedisModule_GetBlockedClientReadyKey(ctx);
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, keyname, REDISMODULE_WRITE, 0, &fsl, 0) || !fsl)
+        return REDISMODULE_ERR;
+
+    RedisModule_Assert(fsl->length);
+    RedisModule_ReplyWithLongLong(ctx, fsl->list[--fsl->length]);
+
+    /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+int bpop_timeout_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithSimpleString(ctx, "Request timedout");
+}
+
+/* FSL.BPOP <key> <timeout> [NO_TO_CB]- Block clients until list has two or more elements.
+ * When that happens, unblock client and pop the last two elements (from the right). */
+int fsl_bpop(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3)
+        return RedisModule_WrongArity(ctx);
+
+    long long timeout;
+    if (RedisModule_StringToLongLong(argv[2],&timeout) != REDISMODULE_OK || timeout < 0)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid timeout");
+
+    int to_cb = 1;
+    if (argc == 4) {
+        if (strcasecmp("NO_TO_CB", RedisModule_StringPtrLen(argv[3], NULL)))
+            return RedisModule_ReplyWithError(ctx,"ERR invalid argument");
+        to_cb = 0;
+    }
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_WRITE, 0, &fsl, 1))
+        return REDISMODULE_OK;
+
+    if (!fsl) {
+        RedisModule_BlockClientOnKeys(ctx, bpop_reply_callback, to_cb ? bpop_timeout_callback : NULL,
+                                      NULL, timeout, &argv[1], 1, NULL);
+    } else {
+        RedisModule_Assert(fsl->length);
+        RedisModule_ReplyWithLongLong(ctx, fsl->list[--fsl->length]);
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int bpopgt_reply_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleString *keyname = RedisModule_GetBlockedClientReadyKey(ctx);
+    long long *pgt = RedisModule_GetBlockedClientPrivateData(ctx);
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, keyname, REDISMODULE_WRITE, 0, &fsl, 0) || !fsl)
+        return RedisModule_ReplyWithError(ctx,"UNBLOCKED key no longer exists");
+
+    if (fsl->list[fsl->length-1] <= *pgt)
+        return REDISMODULE_ERR;
+
+    RedisModule_Assert(fsl->length);
+    RedisModule_ReplyWithLongLong(ctx, fsl->list[--fsl->length]);
+    /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+int bpopgt_timeout_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithSimpleString(ctx, "Request timedout");
+}
+
+void bpopgt_free_privdata(RedisModuleCtx *ctx, void *privdata) {
+    REDISMODULE_NOT_USED(ctx);
+    RedisModule_Free(privdata);
+}
+
+/* FSL.BPOPGT <key> <gt> <timeout> - Block clients until list has an element greater than <gt>.
+ * When that happens, unblock client and pop the last element (from the right). */
+int fsl_bpopgt(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4)
+        return RedisModule_WrongArity(ctx);
+
+    long long gt;
+    if (RedisModule_StringToLongLong(argv[2],&gt) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid integer");
+
+    long long timeout;
+    if (RedisModule_StringToLongLong(argv[3],&timeout) != REDISMODULE_OK || timeout < 0)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid timeout");
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_WRITE, 0, &fsl, 1))
+        return REDISMODULE_OK;
+
+    if (!fsl)
+        return RedisModule_ReplyWithError(ctx,"ERR key must exist");
+
+    if (fsl->list[fsl->length-1] <= gt) {
+        /* We use malloc so the tests in blockedonkeys.tcl can check for memory leaks */
+        long long *pgt = RedisModule_Alloc(sizeof(long long));
+        *pgt = gt;
+        RedisModule_BlockClientOnKeysWithFlags(
+            ctx, bpopgt_reply_callback, bpopgt_timeout_callback,
+            bpopgt_free_privdata, timeout, &argv[1], 1, pgt,
+            REDISMODULE_BLOCK_UNBLOCK_DELETED);
+    } else {
+        RedisModule_Assert(fsl->length);
+        RedisModule_ReplyWithLongLong(ctx, fsl->list[--fsl->length]);
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int bpoppush_reply_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleString *src_keyname = RedisModule_GetBlockedClientReadyKey(ctx);
+    RedisModuleString *dst_keyname = RedisModule_GetBlockedClientPrivateData(ctx);
+
+    fsl_t *src;
+    if (!get_fsl(ctx, src_keyname, REDISMODULE_WRITE, 0, &src, 0) || !src)
+        return REDISMODULE_ERR;
+
+    fsl_t *dst;
+    if (!get_fsl(ctx, dst_keyname, REDISMODULE_WRITE, 1, &dst, 0) || !dst)
+        return REDISMODULE_ERR;
+
+    RedisModule_Assert(src->length);
+    long long ele = src->list[--src->length];
+    dst->list[dst->length++] = ele;
+    RedisModule_SignalKeyAsReady(ctx, dst_keyname);
+    /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+    RedisModule_ReplicateVerbatim(ctx);
+    return RedisModule_ReplyWithLongLong(ctx, ele);
+}
+
+int bpoppush_timeout_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithSimpleString(ctx, "Request timedout");
+}
+
+void bpoppush_free_privdata(RedisModuleCtx *ctx, void *privdata) {
+    RedisModule_FreeString(ctx, privdata);
+}
+
+/* FSL.BPOPPUSH <src> <dst> <timeout> - Block clients until <src> has an element.
+ * When that happens, unblock client, pop the last element from <src> and push it to <dst>
+ * (from the right). */
+int fsl_bpoppush(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4)
+        return RedisModule_WrongArity(ctx);
+
+    long long timeout;
+    if (RedisModule_StringToLongLong(argv[3],&timeout) != REDISMODULE_OK || timeout < 0)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid timeout");
+
+    fsl_t *src;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_WRITE, 0, &src, 1))
+        return REDISMODULE_OK;
+
+    if (!src) {
+        /* Retain string for reply callback */
+        RedisModule_RetainString(ctx, argv[2]);
+        /* Key is empty, we must block */
+        RedisModule_BlockClientOnKeys(ctx, bpoppush_reply_callback, bpoppush_timeout_callback,
+                                      bpoppush_free_privdata, timeout, &argv[1], 1, argv[2]);
+    } else {
+        fsl_t *dst;
+        if (!get_fsl(ctx, argv[2], REDISMODULE_WRITE, 1, &dst, 1))
+            return REDISMODULE_OK;
+
+        RedisModule_Assert(src->length);
+        long long ele = src->list[--src->length];
+        dst->list[dst->length++] = ele;
+        RedisModule_SignalKeyAsReady(ctx, argv[2]);
+        RedisModule_ReplyWithLongLong(ctx, ele);
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+    }
+
+    return REDISMODULE_OK;
+}
+
+/* FSL.GETALL <key> - Reply with an array containing all elements. */
+int fsl_getall(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    fsl_t *fsl;
+    if (!get_fsl(ctx, argv[1], REDISMODULE_READ, 0, &fsl, 1))
+        return REDISMODULE_OK;
+
+    if (!fsl)
+        return RedisModule_ReplyWithArray(ctx, 0);
+
+    RedisModule_ReplyWithArray(ctx, fsl->length);
+    for (int i = 0; i < fsl->length; i++)
+        RedisModule_ReplyWithLongLong(ctx, fsl->list[i]);
+    return REDISMODULE_OK;
+}
+
+/* Callback for blockonkeys_popall */
+int blockonkeys_popall_reply_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_LIST) {
+        RedisModuleString *elem;
+        long len = 0;
+        RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_ARRAY_LEN);
+        while ((elem = RedisModule_ListPop(key, REDISMODULE_LIST_HEAD)) != NULL) {
+            len++;
+            RedisModule_ReplyWithString(ctx, elem);
+            RedisModule_FreeString(ctx, elem);
+        }
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+        RedisModule_ReplySetArrayLength(ctx, len);
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR Not a list");
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int blockonkeys_popall_timeout_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithError(ctx, "ERR Timeout");
+}
+
+/* BLOCKONKEYS.POPALL key
+ *
+ * Blocks on an empty key for up to 3 seconds. When unblocked by a list
+ * operation like LPUSH, all the elements are popped and returned. Fails with an
+ * error on timeout. */
+int blockonkeys_popall(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_EMPTY) {
+        RedisModule_BlockClientOnKeys(ctx, blockonkeys_popall_reply_callback,
+                                      blockonkeys_popall_timeout_callback,
+                                      NULL, 3000, &argv[1], 1, NULL);
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR Key not empty");
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* BLOCKONKEYS.LPUSH key val [val ..]
+ * BLOCKONKEYS.LPUSH_UNBLOCK key val [val ..]
+ *
+ * A module equivalent of LPUSH. If the name LPUSH_UNBLOCK is used,
+ * RM_SignalKeyAsReady() is also called. */
+int blockonkeys_lpush(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_KeyType(key) != REDISMODULE_KEYTYPE_EMPTY &&
+        RedisModule_KeyType(key) != REDISMODULE_KEYTYPE_LIST) {
+        RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    } else {
+        for (int i = 2; i < argc; i++) {
+            if (RedisModule_ListPush(key, REDISMODULE_LIST_HEAD,
+                                     argv[i]) != REDISMODULE_OK) {
+                RedisModule_CloseKey(key);
+                return RedisModule_ReplyWithError(ctx, "ERR Push failed");
+            }
+        }
+    }
+    RedisModule_CloseKey(key);
+
+    /* signal key as ready if the command is lpush_unblock */
+    size_t len;
+    const char *str = RedisModule_StringPtrLen(argv[0], &len);
+    if (!strncasecmp(str, "blockonkeys.lpush_unblock", len)) {
+        RedisModule_SignalKeyAsReady(ctx, argv[1]);
+    }
+    RedisModule_ReplicateVerbatim(ctx);
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+/* Callback for the BLOCKONKEYS.BLPOPN command */
+int blockonkeys_blpopn_reply_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argc);
+    long long n;
+    RedisModule_StringToLongLong(argv[2], &n);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    int result;
+    if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_LIST &&
+        RedisModule_ValueLength(key) >= (size_t)n) {
+        RedisModule_ReplyWithArray(ctx, n);
+        for (long i = 0; i < n; i++) {
+            RedisModuleString *elem = RedisModule_ListPop(key, REDISMODULE_LIST_HEAD);
+            RedisModule_ReplyWithString(ctx, elem);
+            RedisModule_FreeString(ctx, elem);
+        }
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+        result = REDISMODULE_OK;
+    } else if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_LIST ||
+               RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_EMPTY) {
+        const char *module_cmd = RedisModule_StringPtrLen(argv[0], NULL);
+        if (!strcasecmp(module_cmd, "blockonkeys.blpopn_or_unblock"))
+            RedisModule_UnblockClient(RedisModule_GetBlockedClientHandle(ctx), NULL);
+
+        /* continue blocking */
+        result = REDISMODULE_ERR;
+    } else {
+        result = RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+    RedisModule_CloseKey(key);
+    return result;
+}
+
+int blockonkeys_blpopn_timeout_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithError(ctx, "ERR Timeout");
+}
+
+int blockonkeys_blpopn_abort_callback(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithSimpleString(ctx, "Action aborted");
+}
+
+/* BLOCKONKEYS.BLPOPN key N
+ *
+ * Blocks until key has N elements and then pops them or fails after 3 seconds.
+ */
+int blockonkeys_blpopn(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3) return RedisModule_WrongArity(ctx);
+
+    long long n, timeout = 3000LL;
+    if (RedisModule_StringToLongLong(argv[2], &n) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx, "ERR Invalid N");
+    }
+
+    if (argc > 3 ) {
+        if (RedisModule_StringToLongLong(argv[3], &timeout) != REDISMODULE_OK) {
+            return RedisModule_ReplyWithError(ctx, "ERR Invalid timeout value");
+        }
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    int keytype = RedisModule_KeyType(key);
+    if (keytype != REDISMODULE_KEYTYPE_EMPTY &&
+        keytype != REDISMODULE_KEYTYPE_LIST) {
+        RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    } else if (keytype == REDISMODULE_KEYTYPE_LIST &&
+               RedisModule_ValueLength(key) >= (size_t)n) {
+        RedisModule_ReplyWithArray(ctx, n);
+        for (long i = 0; i < n; i++) {
+            RedisModuleString *elem = RedisModule_ListPop(key, REDISMODULE_LIST_HEAD);
+            RedisModule_ReplyWithString(ctx, elem);
+            RedisModule_FreeString(ctx, elem);
+        }
+        /* I'm lazy so i'll replicate a potentially blocking command, it shouldn't block in this flow. */
+        RedisModule_ReplicateVerbatim(ctx);
+    } else {
+        RedisModule_BlockClientOnKeys(ctx, blockonkeys_blpopn_reply_callback,
+                                      timeout ? blockonkeys_blpopn_timeout_callback : blockonkeys_blpopn_abort_callback,
+                                      NULL, timeout, &argv[1], 1, NULL);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "blockonkeys", 1, REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleTypeMethods tm = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = fsl_rdb_load,
+        .rdb_save = fsl_rdb_save,
+        .aof_rewrite = fsl_aofrw,
+        .mem_usage = NULL,
+        .free = fsl_free,
+        .digest = NULL,
+    };
+
+    fsltype = RedisModule_CreateDataType(ctx, "fsltype_t", 0, &tm);
+    if (fsltype == NULL)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.push",fsl_push,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.pushtimer",fsl_pushtimer,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.bpop",fsl_bpop,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.bpopgt",fsl_bpopgt,"write",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.bpoppush",fsl_bpoppush,"write",1,2,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fsl.getall",fsl_getall,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blockonkeys.popall", blockonkeys_popall,
+                                  "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blockonkeys.lpush", blockonkeys_lpush,
+                                  "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blockonkeys.lpush_unblock", blockonkeys_lpush,
+                                  "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blockonkeys.blpopn", blockonkeys_blpopn,
+                                  "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "blockonkeys.blpopn_or_unblock", blockonkeys_blpopn,
+                                      "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/cmdintrospection.c b/tests/modules/cmdintrospection.c
new file mode 100644
index 0000000..1a5e486
--- /dev/null
+++ b/tests/modules/cmdintrospection.c
@@ -0,0 +1,158 @@
+#include "redismodule.h"
+
+#define UNUSED(V) ((void) V)
+
+int cmd_xadd(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "cmdintrospection", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"cmdintrospection.xadd",cmd_xadd,"write deny-oom random fast",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *xadd = RedisModule_GetCommand(ctx,"cmdintrospection.xadd");
+
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .arity = -5,
+        .summary = "Appends a new message to a stream. Creates the key if it doesn't exist.",
+        .since = "5.0.0",
+        .complexity = "O(1) when adding a new entry, O(N) when trimming where N being the number of entries evicted.",
+        .tips = "nondeterministic_output",
+        .history = (RedisModuleCommandHistoryEntry[]){
+            /* NOTE: All versions specified should be the module's versions, not
+             * Redis'! We use Redis versions in this example for the purpose of
+             * testing (comparing the output with the output of the vanilla
+             * XADD). */
+            {"6.2.0", "Added the `NOMKSTREAM` option, `MINID` trimming strategy and the `LIMIT` option."},
+            {"7.0.0", "Added support for the `<ms>-*` explicit ID form."},
+            {0}
+        },
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .notes = "UPDATE instead of INSERT because of the optional trimming feature",
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {0}
+        },
+        .args = (RedisModuleCommandArg[]){
+            {
+                .name = "key",
+                .type = REDISMODULE_ARG_TYPE_KEY,
+                .key_spec_index = 0
+            },
+            {
+                .name = "nomkstream",
+                .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                .token = "NOMKSTREAM",
+                .since = "6.2.0",
+                .flags = REDISMODULE_CMD_ARG_OPTIONAL
+            },
+            {
+                .name = "trim",
+                .type = REDISMODULE_ARG_TYPE_BLOCK,
+                .flags = REDISMODULE_CMD_ARG_OPTIONAL,
+                .subargs = (RedisModuleCommandArg[]){
+                    {
+                        .name = "strategy",
+                        .type = REDISMODULE_ARG_TYPE_ONEOF,
+                        .subargs = (RedisModuleCommandArg[]){
+                            {
+                                .name = "maxlen",
+                                .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                                .token = "MAXLEN",
+                            },
+                            {
+                                .name = "minid",
+                                .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                                .token = "MINID",
+                                .since = "6.2.0",
+                            },
+                            {0}
+                        }
+                    },
+                    {
+                        .name = "operator",
+                        .type = REDISMODULE_ARG_TYPE_ONEOF,
+                        .flags = REDISMODULE_CMD_ARG_OPTIONAL,
+                        .subargs = (RedisModuleCommandArg[]){
+                            {
+                                .name = "equal",
+                                .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                                .token = "="
+                            },
+                            {
+                                .name = "approximately",
+                                .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                                .token = "~"
+                            },
+                            {0}
+                        }
+                    },
+                    {
+                        .name = "threshold",
+                        .type = REDISMODULE_ARG_TYPE_STRING,
+                        .display_text = "threshold" /* Just for coverage, doesn't have a visible effect */
+                    },
+                    {
+                        .name = "count",
+                        .type = REDISMODULE_ARG_TYPE_INTEGER,
+                        .token = "LIMIT",
+                        .since = "6.2.0",
+                        .flags = REDISMODULE_CMD_ARG_OPTIONAL
+                    },
+                    {0}
+                }
+            },
+            {
+                .name = "id-selector",
+                .type = REDISMODULE_ARG_TYPE_ONEOF,
+                .subargs = (RedisModuleCommandArg[]){
+                    {
+                        .name = "auto-id",
+                        .type = REDISMODULE_ARG_TYPE_PURE_TOKEN,
+                        .token = "*"
+                    },
+                    {
+                        .name = "id",
+                        .type = REDISMODULE_ARG_TYPE_STRING,
+                    },
+                    {0}
+                }
+            },
+            {
+                .name = "data",
+                .type = REDISMODULE_ARG_TYPE_BLOCK,
+                .flags = REDISMODULE_CMD_ARG_MULTIPLE,
+                .subargs = (RedisModuleCommandArg[]){
+                    {
+                        .name = "field",
+                        .type = REDISMODULE_ARG_TYPE_STRING,
+                    },
+                    {
+                        .name = "value",
+                        .type = REDISMODULE_ARG_TYPE_STRING,
+                    },
+                    {0}
+                }
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(xadd, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/commandfilter.c b/tests/modules/commandfilter.c
new file mode 100644
index 0000000..56e517a
--- /dev/null
+++ b/tests/modules/commandfilter.c
@@ -0,0 +1,251 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <strings.h>
+
+static RedisModuleString *log_key_name;
+
+static const char log_command_name[] = "commandfilter.log";
+static const char ping_command_name[] = "commandfilter.ping";
+static const char retained_command_name[] = "commandfilter.retained";
+static const char unregister_command_name[] = "commandfilter.unregister";
+static const char unfiltered_clientid_name[] = "unfilter_clientid";
+static int in_log_command = 0;
+
+unsigned long long unfiltered_clientid = 0;
+
+static RedisModuleCommandFilter *filter, *filter1;
+static RedisModuleString *retained;
+
+int CommandFilter_UnregisterCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    (void) argc;
+    (void) argv;
+
+    RedisModule_ReplyWithLongLong(ctx,
+            RedisModule_UnregisterCommandFilter(ctx, filter));
+
+    return REDISMODULE_OK;
+}
+
+int CommandFilter_PingCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    (void) argc;
+    (void) argv;
+
+    RedisModuleCallReply *reply = RedisModule_Call(ctx, "ping", "c", "@log");
+    if (reply) {
+        RedisModule_ReplyWithCallReply(ctx, reply);
+        RedisModule_FreeCallReply(reply);
+    } else {
+        RedisModule_ReplyWithSimpleString(ctx, "Unknown command or invalid arguments");
+    }
+
+    return REDISMODULE_OK;
+}
+
+int CommandFilter_Retained(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    (void) argc;
+    (void) argv;
+
+    if (retained) {
+        RedisModule_ReplyWithString(ctx, retained);
+    } else {
+        RedisModule_ReplyWithNull(ctx);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int CommandFilter_LogCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    RedisModuleString *s = RedisModule_CreateString(ctx, "", 0);
+
+    int i;
+    for (i = 1; i < argc; i++) {
+        size_t arglen;
+        const char *arg = RedisModule_StringPtrLen(argv[i], &arglen);
+
+        if (i > 1) RedisModule_StringAppendBuffer(ctx, s, " ", 1);
+        RedisModule_StringAppendBuffer(ctx, s, arg, arglen);
+    }
+
+    RedisModuleKey *log = RedisModule_OpenKey(ctx, log_key_name, REDISMODULE_WRITE|REDISMODULE_READ);
+    RedisModule_ListPush(log, REDISMODULE_LIST_HEAD, s);
+    RedisModule_CloseKey(log);
+    RedisModule_FreeString(ctx, s);
+
+    in_log_command = 1;
+
+    size_t cmdlen;
+    const char *cmdname = RedisModule_StringPtrLen(argv[1], &cmdlen);
+    RedisModuleCallReply *reply = RedisModule_Call(ctx, cmdname, "v", &argv[2], argc - 2);
+    if (reply) {
+        RedisModule_ReplyWithCallReply(ctx, reply);
+        RedisModule_FreeCallReply(reply);
+    } else {
+        RedisModule_ReplyWithSimpleString(ctx, "Unknown command or invalid arguments");
+    }
+
+    in_log_command = 0;
+
+    return REDISMODULE_OK;
+}
+
+int CommandFilter_UnfilteredClientId(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc < 2)
+        return RedisModule_WrongArity(ctx);
+
+    long long id;
+    if (RedisModule_StringToLongLong(argv[1], &id) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "invalid client id");
+        return REDISMODULE_OK;
+    }
+    if (id < 0) {
+        RedisModule_ReplyWithError(ctx, "invalid client id");
+        return REDISMODULE_OK;
+    }
+
+    unfiltered_clientid = id;
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* Filter to protect against Bug #11894 reappearing
+ *
+ * ensures that the filter is only run the first time through, and not on reprocessing
+ */
+void CommandFilter_BlmoveSwap(RedisModuleCommandFilterCtx *filter)
+{
+    if (RedisModule_CommandFilterArgsCount(filter) != 6)
+        return;
+
+    RedisModuleString *arg = RedisModule_CommandFilterArgGet(filter, 0);
+    size_t arg_len;
+    const char *arg_str = RedisModule_StringPtrLen(arg, &arg_len);
+
+    if (arg_len != 6 || strncmp(arg_str, "blmove", 6))
+        return;
+
+    /*
+     * Swapping directional args (right/left) from source and destination.
+     * need to hold here, can't push into the ArgReplace func, as it will cause other to freed -> use after free
+     */
+    RedisModuleString *dir1 = RedisModule_HoldString(NULL, RedisModule_CommandFilterArgGet(filter, 3));
+    RedisModuleString *dir2 = RedisModule_HoldString(NULL, RedisModule_CommandFilterArgGet(filter, 4));
+    RedisModule_CommandFilterArgReplace(filter, 3, dir2);
+    RedisModule_CommandFilterArgReplace(filter, 4, dir1);
+}
+
+void CommandFilter_CommandFilter(RedisModuleCommandFilterCtx *filter)
+{
+    unsigned long long id = RedisModule_CommandFilterGetClientId(filter);
+    if (id == unfiltered_clientid) return;
+
+    if (in_log_command) return;  /* don't process our own RM_Call() from CommandFilter_LogCommand() */
+
+    /* Fun manipulations:
+     * - Remove @delme
+     * - Replace @replaceme
+     * - Append @insertbefore or @insertafter
+     * - Prefix with Log command if @log encountered
+     */
+    int log = 0;
+    int pos = 0;
+    while (pos < RedisModule_CommandFilterArgsCount(filter)) {
+        const RedisModuleString *arg = RedisModule_CommandFilterArgGet(filter, pos);
+        size_t arg_len;
+        const char *arg_str = RedisModule_StringPtrLen(arg, &arg_len);
+
+        if (arg_len == 6 && !memcmp(arg_str, "@delme", 6)) {
+            RedisModule_CommandFilterArgDelete(filter, pos);
+            continue;
+        } 
+        if (arg_len == 10 && !memcmp(arg_str, "@replaceme", 10)) {
+            RedisModule_CommandFilterArgReplace(filter, pos,
+                    RedisModule_CreateString(NULL, "--replaced--", 12));
+        } else if (arg_len == 13 && !memcmp(arg_str, "@insertbefore", 13)) {
+            RedisModule_CommandFilterArgInsert(filter, pos,
+                    RedisModule_CreateString(NULL, "--inserted-before--", 19));
+            pos++;
+        } else if (arg_len == 12 && !memcmp(arg_str, "@insertafter", 12)) {
+            RedisModule_CommandFilterArgInsert(filter, pos + 1,
+                    RedisModule_CreateString(NULL, "--inserted-after--", 18));
+            pos++;
+        } else if (arg_len == 7 && !memcmp(arg_str, "@retain", 7)) {
+            if (retained) RedisModule_FreeString(NULL, retained);
+            retained = RedisModule_CommandFilterArgGet(filter, pos + 1);
+            RedisModule_RetainString(NULL, retained);
+            pos++;
+        } else if (arg_len == 4 && !memcmp(arg_str, "@log", 4)) {
+            log = 1;
+        }
+        pos++;
+    }
+
+    if (log) RedisModule_CommandFilterArgInsert(filter, 0,
+            RedisModule_CreateString(NULL, log_command_name, sizeof(log_command_name)-1));
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (RedisModule_Init(ctx,"commandfilter",1,REDISMODULE_APIVER_1)
+            == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (argc != 2 && argc != 3) {
+        RedisModule_Log(ctx, "warning", "Log key name not specified");
+        return REDISMODULE_ERR;
+    }
+
+    long long noself = 0;
+    log_key_name = RedisModule_CreateStringFromString(ctx, argv[0]);
+    RedisModule_StringToLongLong(argv[1], &noself);
+    retained = NULL;
+
+    if (RedisModule_CreateCommand(ctx,log_command_name,
+                CommandFilter_LogCommand,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,ping_command_name,
+                CommandFilter_PingCommand,"deny-oom",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,retained_command_name,
+                CommandFilter_Retained,"readonly",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,unregister_command_name,
+                CommandFilter_UnregisterCommand,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, unfiltered_clientid_name,
+                CommandFilter_UnfilteredClientId, "admin", 1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if ((filter = RedisModule_RegisterCommandFilter(ctx, CommandFilter_CommandFilter, 
+                    noself ? REDISMODULE_CMDFILTER_NOSELF : 0))
+            == NULL) return REDISMODULE_ERR;
+
+    if ((filter1 = RedisModule_RegisterCommandFilter(ctx, CommandFilter_BlmoveSwap, 0)) == NULL)
+        return REDISMODULE_ERR;
+
+    if (argc == 3) {
+        const char *ptr = RedisModule_StringPtrLen(argv[2], NULL);
+        if (!strcasecmp(ptr, "noload")) {
+            /* This is a hint that we return ERR at the last moment of OnLoad. */
+            RedisModule_FreeString(ctx, log_key_name);
+            if (retained) RedisModule_FreeString(NULL, retained);
+            return REDISMODULE_ERR;
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    RedisModule_FreeString(ctx, log_key_name);
+    if (retained) RedisModule_FreeString(NULL, retained);
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/datatype.c b/tests/modules/datatype.c
new file mode 100644
index 0000000..408d1a5
--- /dev/null
+++ b/tests/modules/datatype.c
@@ -0,0 +1,314 @@
+/* This module current tests a small subset but should be extended in the future
+ * for general ModuleDataType coverage.
+ */
+
+/* define macros for having usleep */
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE
+#include <unistd.h>
+
+#include "redismodule.h"
+
+static RedisModuleType *datatype = NULL;
+static int load_encver = 0;
+
+/* used to test processing events during slow loading */
+static volatile int slow_loading = 0;
+static volatile int is_in_slow_loading = 0;
+
+#define DATATYPE_ENC_VER 1
+
+typedef struct {
+    long long intval;
+    RedisModuleString *strval;
+} DataType;
+
+static void *datatype_load(RedisModuleIO *io, int encver) {
+    load_encver = encver;
+    int intval = RedisModule_LoadSigned(io);
+    if (RedisModule_IsIOError(io)) return NULL;
+
+    RedisModuleString *strval = RedisModule_LoadString(io);
+    if (RedisModule_IsIOError(io)) return NULL;
+
+    DataType *dt = (DataType *) RedisModule_Alloc(sizeof(DataType));
+    dt->intval = intval;
+    dt->strval = strval;
+
+    if (slow_loading) {
+        RedisModuleCtx *ctx = RedisModule_GetContextFromIO(io);
+        is_in_slow_loading = 1;
+        while (slow_loading) {
+            RedisModule_Yield(ctx, REDISMODULE_YIELD_FLAG_CLIENTS, "Slow module operation");
+            usleep(1000);
+        }
+        is_in_slow_loading = 0;
+    }
+
+    return dt;
+}
+
+static void datatype_save(RedisModuleIO *io, void *value) {
+    DataType *dt = (DataType *) value;
+    RedisModule_SaveSigned(io, dt->intval);
+    RedisModule_SaveString(io, dt->strval);
+}
+
+static void datatype_free(void *value) {
+    if (value) {
+        DataType *dt = (DataType *) value;
+
+        if (dt->strval) RedisModule_FreeString(NULL, dt->strval);
+        RedisModule_Free(dt);
+    }
+}
+
+static void *datatype_copy(RedisModuleString *fromkey, RedisModuleString *tokey, const void *value) {
+    const DataType *old = value;
+
+    /* Answers to ultimate questions cannot be copied! */
+    if (old->intval == 42)
+        return NULL;
+
+    DataType *new = (DataType *) RedisModule_Alloc(sizeof(DataType));
+
+    new->intval = old->intval;
+    new->strval = RedisModule_CreateStringFromString(NULL, old->strval);
+
+    /* Breaking the rules here! We return a copy that also includes traces
+     * of fromkey/tokey to confirm we get what we expect.
+     */
+    size_t len;
+    const char *str = RedisModule_StringPtrLen(fromkey, &len);
+    RedisModule_StringAppendBuffer(NULL, new->strval, "/", 1);
+    RedisModule_StringAppendBuffer(NULL, new->strval, str, len);
+    RedisModule_StringAppendBuffer(NULL, new->strval, "/", 1);
+    str = RedisModule_StringPtrLen(tokey, &len);
+    RedisModule_StringAppendBuffer(NULL, new->strval, str, len);
+
+    return new;
+}
+
+static int datatype_set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long intval;
+
+    if (RedisModule_StringToLongLong(argv[2], &intval) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    DataType *dt = RedisModule_Calloc(sizeof(DataType), 1);
+    dt->intval = intval;
+    dt->strval = argv[3];
+    RedisModule_RetainString(ctx, dt->strval);
+
+    RedisModule_ModuleTypeSetValue(key, datatype, dt);
+    RedisModule_CloseKey(key);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+    return REDISMODULE_OK;
+}
+
+static int datatype_restore(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long encver;
+    if (RedisModule_StringToLongLong(argv[3], &encver) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+
+    DataType *dt = RedisModule_LoadDataTypeFromStringEncver(argv[2], datatype, encver);
+    if (!dt) {
+        RedisModule_ReplyWithError(ctx, "Invalid data");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    RedisModule_ModuleTypeSetValue(key, datatype, dt);
+    RedisModule_CloseKey(key);
+    RedisModule_ReplyWithLongLong(ctx, load_encver);
+
+    return REDISMODULE_OK;
+}
+
+static int datatype_get(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    DataType *dt = RedisModule_ModuleTypeGetValue(key);
+    RedisModule_CloseKey(key);
+
+    if (!dt) {
+        RedisModule_ReplyWithNullArray(ctx);
+    } else {
+        RedisModule_ReplyWithArray(ctx, 2);
+        RedisModule_ReplyWithLongLong(ctx, dt->intval);
+        RedisModule_ReplyWithString(ctx, dt->strval);
+    }
+    return REDISMODULE_OK;
+}
+
+static int datatype_dump(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    DataType *dt = RedisModule_ModuleTypeGetValue(key);
+    RedisModule_CloseKey(key);
+
+    RedisModuleString *reply = RedisModule_SaveDataTypeToString(ctx, dt, datatype);
+    if (!reply) {
+        RedisModule_ReplyWithError(ctx, "Failed to save");
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithString(ctx, reply);
+    RedisModule_FreeString(ctx, reply);
+    return REDISMODULE_OK;
+}
+
+static int datatype_swap(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *a = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    RedisModuleKey *b = RedisModule_OpenKey(ctx, argv[2], REDISMODULE_WRITE);
+    void *val = RedisModule_ModuleTypeGetValue(a);
+
+    int error = (RedisModule_ModuleTypeReplaceValue(b, datatype, val, &val) == REDISMODULE_ERR ||
+                 RedisModule_ModuleTypeReplaceValue(a, datatype, val, NULL) == REDISMODULE_ERR);
+    if (!error)
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    else
+        RedisModule_ReplyWithError(ctx, "ERR failed");
+
+    RedisModule_CloseKey(a);
+    RedisModule_CloseKey(b);
+
+    return REDISMODULE_OK;
+}
+
+/* used to enable or disable slow loading */
+static int datatype_slow_loading(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long ll;
+    if (RedisModule_StringToLongLong(argv[1], &ll) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+    slow_loading = ll;
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* used to test if we reached the slow loading code */
+static int datatype_is_in_slow_loading(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithLongLong(ctx, is_in_slow_loading);
+    return REDISMODULE_OK;
+}
+
+int createDataTypeBlockCheck(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    static RedisModuleType *datatype_outside_onload = NULL;
+
+    RedisModuleTypeMethods datatype_methods = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = datatype_load,
+        .rdb_save = datatype_save,
+        .free = datatype_free,
+        .copy = datatype_copy
+    };
+
+    datatype_outside_onload = RedisModule_CreateDataType(ctx, "test_dt_outside_onload", 1, &datatype_methods);
+
+    /* This validates that it's not possible to create datatype outside OnLoad,
+     * thus returns an error if it succeeds. */
+    if (datatype_outside_onload == NULL) {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        RedisModule_ReplyWithError(ctx, "UNEXPECTEDOK");
+    }
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"datatype",DATATYPE_ENC_VER,REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Creates a command which creates a datatype outside OnLoad() function. */
+    if (RedisModule_CreateCommand(ctx,"block.create.datatype.outside.onload", createDataTypeBlockCheck, "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModule_SetModuleOptions(ctx, REDISMODULE_OPTIONS_HANDLE_IO_ERRORS);
+
+    RedisModuleTypeMethods datatype_methods = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = datatype_load,
+        .rdb_save = datatype_save,
+        .free = datatype_free,
+        .copy = datatype_copy
+    };
+
+    datatype = RedisModule_CreateDataType(ctx, "test___dt", 1, &datatype_methods);
+    if (datatype == NULL)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"datatype.set", datatype_set,
+                                  "write deny-oom", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"datatype.get", datatype_get,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"datatype.restore", datatype_restore,
+                                  "write deny-oom", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"datatype.dump", datatype_dump,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "datatype.swap", datatype_swap,
+                                  "write", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "datatype.slow_loading", datatype_slow_loading,
+                                  "allow-loading", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "datatype.is_in_slow_loading", datatype_is_in_slow_loading,
+                                  "allow-loading", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/datatype2.c b/tests/modules/datatype2.c
new file mode 100644
index 0000000..bc0dc3d
--- /dev/null
+++ b/tests/modules/datatype2.c
@@ -0,0 +1,739 @@
+/* This module is used to test a use case of a module that stores information
+ * about keys in global memory, and relies on the enhanced data type callbacks to
+ * get key name and dbid on various operations.
+ *
+ * it simulates a simple memory allocator. The smallest allocation unit of 
+ * the allocator is a mem block with a size of 4KB. Multiple mem blocks are combined 
+ * using a linked list. These linked lists are placed in a global dict named 'mem_pool'.
+ * Each db has a 'mem_pool'. You can use the 'mem.alloc' command to allocate a specified 
+ * number of mem blocks, and use 'mem.free' to release the memory. Use 'mem.write', 'mem.read'
+ * to write and read the specified mem block (note that each mem block can only be written once).
+ * Use 'mem.usage' to get the memory usage under different dbs, and it will return the size 
+ * mem blocks and used mem blocks under the db.
+ * The specific structure diagram is as follows:
+ * 
+ * 
+ * Global variables of the module:
+ * 
+ *                                           mem blocks link
+ *                          ┌─────┬─────┐
+ *                          │     │     │    ┌───┐    ┌───┐    ┌───┐
+ *                          │ k1  │  ───┼───►│4KB├───►│4KB├───►│4KB│
+ *                          │     │     │    └───┘    └───┘    └───┘
+ *                          ├─────┼─────┤
+ *    ┌───────┐      ┌────► │     │     │    ┌───┐    ┌───┐
+ *    │       │      │      │ k2  │  ───┼───►│4KB├───►│4KB│
+ *    │ db0   ├──────┘      │     │     │    └───┘    └───┘
+ *    │       │             ├─────┼─────┤
+ *    ├───────┤             │     │     │    ┌───┐    ┌───┐    ┌───┐
+ *    │       │             │ k3  │  ───┼───►│4KB├───►│4KB├───►│4KB│
+ *    │ db1   ├──►null      │     │     │    └───┘    └───┘    └───┘
+ *    │       │             └─────┴─────┘
+ *    ├───────┤                  dict
+ *    │       │
+ *    │ db2   ├─────────┐
+ *    │       │         │
+ *    ├───────┤         │   ┌─────┬─────┐
+ *    │       │         │   │     │     │    ┌───┐    ┌───┐    ┌───┐
+ *    │ db3   ├──►null  │   │ k1  │  ───┼───►│4KB├───►│4KB├───►│4KB│
+ *    │       │         │   │     │     │    └───┘    └───┘    └───┘
+ *    └───────┘         │   ├─────┼─────┤
+ * mem_pool[MAX_DB]     │   │     │     │    ┌───┐    ┌───┐
+ *                      └──►│ k2  │  ───┼───►│4KB├───►│4KB│
+ *                          │     │     │    └───┘    └───┘
+ *                          └─────┴─────┘
+ *                               dict
+ * 
+ * 
+ * Keys in redis database:
+ * 
+ *                                ┌───────┐
+ *                                │ size  │
+ *                   ┌───────────►│ used  │
+ *                   │            │ mask  │
+ *     ┌─────┬─────┐ │            └───────┘                                   ┌───────┐
+ *     │     │     │ │          MemAllocObject                                │ size  │
+ *     │ k1  │  ───┼─┘                                           ┌───────────►│ used  │
+ *     │     │     │                                             │            │ mask  │
+ *     ├─────┼─────┤              ┌───────┐        ┌─────┬─────┐ │            └───────┘
+ *     │     │     │              │ size  │        │     │     │ │          MemAllocObject
+ *     │ k2  │  ───┼─────────────►│ used  │        │ k1  │  ───┼─┘
+ *     │     │     │              │ mask  │        │     │     │
+ *     ├─────┼─────┤              └───────┘        ├─────┼─────┤
+ *     │     │     │            MemAllocObject     │     │     │
+ *     │ k3  │  ───┼─┐                             │ k2  │  ───┼─┐
+ *     │     │     │ │                             │     │     │ │
+ *     └─────┴─────┘ │            ┌───────┐        └─────┴─────┘ │            ┌───────┐
+ *      redis db[0]  │            │ size  │          redis db[1] │            │ size  │
+ *                   └───────────►│ used  │                      └───────────►│ used  │
+ *                                │ mask  │                                   │ mask  │
+ *                                └───────┘                                   └───────┘
+ *                              MemAllocObject                              MemAllocObject
+ *
+ **/
+
+#include "redismodule.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <stdint.h>
+
+static RedisModuleType *MemAllocType;
+
+#define MAX_DB 16
+RedisModuleDict *mem_pool[MAX_DB];
+typedef struct MemAllocObject {
+    long long size;
+    long long used;
+    uint64_t mask;
+} MemAllocObject;
+
+MemAllocObject *createMemAllocObject(void) {
+    MemAllocObject *o = RedisModule_Calloc(1, sizeof(*o));
+    return o;
+}
+
+/*---------------------------- mem block apis ------------------------------------*/
+#define BLOCK_SIZE 4096
+struct MemBlock {
+    char block[BLOCK_SIZE];
+    struct MemBlock *next;
+};
+
+void MemBlockFree(struct MemBlock *head) {
+    if (head) {
+        struct MemBlock *block = head->next, *next;
+        RedisModule_Free(head);
+        while (block) {
+            next = block->next;
+            RedisModule_Free(block);
+            block = next;
+        }
+    }
+}
+struct MemBlock *MemBlockCreate(long long num) {
+    if (num <= 0) {
+        return NULL;
+    }
+
+    struct MemBlock *head = RedisModule_Calloc(1, sizeof(struct MemBlock));
+    struct MemBlock *block = head;
+    while (--num) {
+        block->next = RedisModule_Calloc(1, sizeof(struct MemBlock));
+        block = block->next;
+    }
+
+    return head;
+}
+
+long long MemBlockNum(const struct MemBlock *head) {
+    long long num = 0;
+    const struct MemBlock *block = head;
+    while (block) {
+        num++;
+        block = block->next;
+    }
+
+    return num;
+}
+
+size_t MemBlockWrite(struct MemBlock *head, long long block_index, const char *data, size_t size) {
+    size_t w_size = 0;
+    struct MemBlock *block = head;
+    while (block_index-- && block) {
+        block = block->next;
+    }
+
+    if (block) {
+        size = size > BLOCK_SIZE ? BLOCK_SIZE:size;
+        memcpy(block->block, data, size);
+        w_size += size;
+    }
+
+    return w_size;
+}
+
+int MemBlockRead(struct MemBlock *head, long long block_index, char *data, size_t size) {
+    size_t r_size = 0;
+    struct MemBlock *block = head;
+    while (block_index-- && block) {
+        block = block->next;
+    }
+
+    if (block) {
+        size = size > BLOCK_SIZE ? BLOCK_SIZE:size;
+        memcpy(data, block->block, size);
+        r_size += size;
+    }
+
+    return r_size;
+}
+
+void MemPoolFreeDb(RedisModuleCtx *ctx, int dbid) {
+    RedisModuleString *key;
+    void *tdata;
+    RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(mem_pool[dbid], "^", NULL, 0);
+    while((key = RedisModule_DictNext(ctx, iter, &tdata)) != NULL) {
+        MemBlockFree((struct MemBlock *)tdata);
+    }
+    RedisModule_DictIteratorStop(iter);
+    RedisModule_FreeDict(NULL, mem_pool[dbid]);
+    mem_pool[dbid] = RedisModule_CreateDict(NULL);
+}
+
+struct MemBlock *MemBlockClone(const struct MemBlock *head) {
+    struct MemBlock *newhead = NULL;
+    if (head) {
+        newhead = RedisModule_Calloc(1, sizeof(struct MemBlock));
+        memcpy(newhead->block, head->block, BLOCK_SIZE);
+        struct MemBlock *newblock = newhead;
+        const struct MemBlock *oldblock = head->next;
+        while (oldblock) {
+            newblock->next = RedisModule_Calloc(1, sizeof(struct MemBlock));
+            newblock = newblock->next;
+            memcpy(newblock->block, oldblock->block, BLOCK_SIZE);
+            oldblock = oldblock->next;
+        }
+    }
+
+    return newhead;
+}
+
+/*---------------------------- event handler ------------------------------------*/
+void swapDbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(sub);
+
+    RedisModuleSwapDbInfo *ei = data;
+
+    // swap
+    RedisModuleDict *tmp = mem_pool[ei->dbnum_first];
+    mem_pool[ei->dbnum_first] = mem_pool[ei->dbnum_second];
+    mem_pool[ei->dbnum_second] = tmp;
+}
+
+void flushdbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(e);
+    int i;
+    RedisModuleFlushInfo *fi = data;
+
+    RedisModule_AutoMemory(ctx);
+
+    if (sub == REDISMODULE_SUBEVENT_FLUSHDB_START) {
+        if (fi->dbnum != -1) {
+           MemPoolFreeDb(ctx, fi->dbnum);
+        } else {
+            for (i = 0; i < MAX_DB; i++) {
+                MemPoolFreeDb(ctx, i);
+            }
+        }
+    }
+}
+
+/*---------------------------- command implementation ------------------------------------*/
+
+/* MEM.ALLOC key block_num */
+int MemAlloc_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc != 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    long long block_num;
+    if ((RedisModule_StringToLongLong(argv[2], &block_num) != REDISMODULE_OK) || block_num <= 0) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid block_num: must be a value greater than 0");
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ | REDISMODULE_WRITE);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(key) != MemAllocType) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    MemAllocObject *o;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        o = createMemAllocObject();
+        RedisModule_ModuleTypeSetValue(key, MemAllocType, o);
+    } else {
+        o = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    struct MemBlock *mem = MemBlockCreate(block_num);
+    RedisModule_Assert(mem != NULL);
+    RedisModule_DictSet(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], mem);
+    o->size = block_num;
+    o->used = 0;
+    o->mask = 0;
+
+    RedisModule_ReplyWithLongLong(ctx, block_num);
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+/* MEM.FREE key */
+int MemFree_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc != 2) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(key) != MemAllocType) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    int ret = 0;
+    MemAllocObject *o;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        RedisModule_ReplyWithLongLong(ctx, ret);
+        return REDISMODULE_OK;
+    } else {
+        o = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    int nokey;
+    struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], &nokey);
+    if (!nokey && mem) {
+        RedisModule_DictDel(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], NULL);
+        MemBlockFree(mem);
+        o->used = 0;
+        o->size = 0;
+        o->mask = 0;
+        ret = 1;
+    }
+
+    RedisModule_ReplyWithLongLong(ctx, ret);
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+/* MEM.WRITE key block_index data */
+int MemWrite_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc != 4) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    long long block_index;
+    if ((RedisModule_StringToLongLong(argv[2], &block_index) != REDISMODULE_OK) || block_index < 0) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid block_index: must be a value greater than 0");
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ | REDISMODULE_WRITE);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(key) != MemAllocType) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    MemAllocObject *o;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        return RedisModule_ReplyWithError(ctx, "ERR Memory has not been allocated");
+    } else {
+        o = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    if (o->mask & (1UL << block_index)) {
+        return RedisModule_ReplyWithError(ctx, "ERR block is busy");
+    }
+
+    int ret = 0;
+    int nokey;
+    struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], &nokey);
+    if (!nokey && mem) {
+        size_t len;
+        const char *buf = RedisModule_StringPtrLen(argv[3], &len);
+        ret = MemBlockWrite(mem, block_index, buf, len);
+        o->mask |= (1UL << block_index);
+        o->used++;
+    }
+
+    RedisModule_ReplyWithLongLong(ctx, ret);
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+/* MEM.READ key block_index */
+int MemRead_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc != 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    long long block_index;
+    if ((RedisModule_StringToLongLong(argv[2], &block_index) != REDISMODULE_OK) || block_index < 0) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid block_index: must be a value greater than 0");
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(key) != MemAllocType) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    MemAllocObject *o;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        return RedisModule_ReplyWithError(ctx, "ERR Memory has not been allocated");
+    } else {
+        o = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    if (!(o->mask & (1UL << block_index))) {
+        return RedisModule_ReplyWithNull(ctx);
+    }
+
+    int nokey;
+    struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], &nokey);
+    RedisModule_Assert(nokey == 0 && mem != NULL);
+     
+    char buf[BLOCK_SIZE];
+    MemBlockRead(mem, block_index, buf, sizeof(buf));
+    
+    /* Assuming that the contents are all c-style strings */
+    RedisModule_ReplyWithStringBuffer(ctx, buf, strlen(buf));
+    return REDISMODULE_OK;
+}
+
+/* MEM.USAGE dbid */
+int MemUsage_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc != 2) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    long long dbid;
+    if ((RedisModule_StringToLongLong(argv[1], (long long *)&dbid) != REDISMODULE_OK)) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid value: must be a integer");
+    }
+
+    if (dbid < 0 || dbid >= MAX_DB) {
+        return RedisModule_ReplyWithError(ctx, "ERR dbid out of range");
+    }
+
+
+    long long size = 0, used = 0;
+
+    void *data;
+    RedisModuleString *key;
+    RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(mem_pool[dbid], "^", NULL, 0);
+    while((key = RedisModule_DictNext(ctx, iter, &data)) != NULL) {
+        int dbbackup = RedisModule_GetSelectedDb(ctx);
+        RedisModule_SelectDb(ctx, dbid);
+        RedisModuleKey *openkey = RedisModule_OpenKey(ctx, key, REDISMODULE_READ);
+        int type = RedisModule_KeyType(openkey);
+        RedisModule_Assert(type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(openkey) == MemAllocType);
+        MemAllocObject *o = RedisModule_ModuleTypeGetValue(openkey);
+        used += o->used;
+        size += o->size;
+        RedisModule_CloseKey(openkey);
+        RedisModule_SelectDb(ctx, dbbackup);
+    }
+    RedisModule_DictIteratorStop(iter);
+
+    RedisModule_ReplyWithArray(ctx, 4);
+    RedisModule_ReplyWithSimpleString(ctx, "total");
+    RedisModule_ReplyWithLongLong(ctx, size);
+    RedisModule_ReplyWithSimpleString(ctx, "used");
+    RedisModule_ReplyWithLongLong(ctx, used);
+    return REDISMODULE_OK;
+}
+
+/* MEM.ALLOCANDWRITE key block_num block_index data block_index data ... */
+int MemAllocAndWrite_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx);  
+
+    if (argc < 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    long long block_num;
+    if ((RedisModule_StringToLongLong(argv[2], &block_num) != REDISMODULE_OK) || block_num <= 0) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid block_num: must be a value greater than 0");
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ | REDISMODULE_WRITE);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY && RedisModule_ModuleTypeGetType(key) != MemAllocType) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    MemAllocObject *o;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        o = createMemAllocObject();
+        RedisModule_ModuleTypeSetValue(key, MemAllocType, o);
+    } else {
+        o = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    struct MemBlock *mem = MemBlockCreate(block_num);
+    RedisModule_Assert(mem != NULL);
+    RedisModule_DictSet(mem_pool[RedisModule_GetSelectedDb(ctx)], argv[1], mem);
+    o->used = 0;
+    o->mask = 0;
+    o->size = block_num;
+
+    int i = 3;
+    long long block_index;
+    for (; i < argc; i++) {
+        /* Security is guaranteed internally, so no security check. */
+        RedisModule_StringToLongLong(argv[i], &block_index);
+        size_t len;
+        const char * buf = RedisModule_StringPtrLen(argv[i + 1], &len);
+        MemBlockWrite(mem, block_index, buf, len);
+        o->used++;
+        o->mask |= (1UL << block_index);
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+/*---------------------------- type callbacks ------------------------------------*/
+
+void *MemAllocRdbLoad(RedisModuleIO *rdb, int encver) {
+    if (encver != 0) {
+        return NULL;
+    }
+
+    MemAllocObject *o = createMemAllocObject();
+    o->size = RedisModule_LoadSigned(rdb);
+    o->used = RedisModule_LoadSigned(rdb);
+    o->mask = RedisModule_LoadUnsigned(rdb);
+
+    const RedisModuleString *key = RedisModule_GetKeyNameFromIO(rdb);
+    int dbid = RedisModule_GetDbIdFromIO(rdb);
+
+    if (o->size) {
+        size_t size;
+        char *tmpbuf;
+        long long num = o->size;
+        struct MemBlock *head = RedisModule_Calloc(1, sizeof(struct MemBlock));
+        tmpbuf = RedisModule_LoadStringBuffer(rdb, &size);
+        memcpy(head->block, tmpbuf, size > BLOCK_SIZE ? BLOCK_SIZE:size);
+        RedisModule_Free(tmpbuf);
+        struct MemBlock *block = head;
+        while (--num) {
+            block->next = RedisModule_Calloc(1, sizeof(struct MemBlock));
+            block = block->next;
+
+            tmpbuf = RedisModule_LoadStringBuffer(rdb, &size);
+            memcpy(block->block, tmpbuf, size > BLOCK_SIZE ? BLOCK_SIZE:size);
+            RedisModule_Free(tmpbuf);
+        }
+
+        RedisModule_DictSet(mem_pool[dbid], (RedisModuleString *)key, head);
+    }
+     
+    return o;
+}
+
+void MemAllocRdbSave(RedisModuleIO *rdb, void *value) {
+    MemAllocObject *o = value;
+    RedisModule_SaveSigned(rdb, o->size);
+    RedisModule_SaveSigned(rdb, o->used);
+    RedisModule_SaveUnsigned(rdb, o->mask);
+
+    const RedisModuleString *key = RedisModule_GetKeyNameFromIO(rdb);
+    int dbid = RedisModule_GetDbIdFromIO(rdb);
+
+    if (o->size) {
+        int nokey;
+        struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[dbid], (RedisModuleString *)key, &nokey);
+        RedisModule_Assert(nokey == 0 && mem != NULL);
+
+        struct MemBlock *block = mem; 
+        while (block) {
+            RedisModule_SaveStringBuffer(rdb, block->block, BLOCK_SIZE);
+            block = block->next;
+        }
+    }
+}
+
+void MemAllocAofRewrite(RedisModuleIO *aof, RedisModuleString *key, void *value) {
+    MemAllocObject *o = (MemAllocObject *)value;
+    if (o->size) {
+        int dbid = RedisModule_GetDbIdFromIO(aof);
+        int nokey;
+        size_t i = 0, j = 0;
+        struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[dbid], (RedisModuleString *)key, &nokey);
+        RedisModule_Assert(nokey == 0 && mem != NULL);
+        size_t array_size = o->size * 2;
+        RedisModuleString ** string_array = RedisModule_Calloc(array_size, sizeof(RedisModuleString *));
+        while (mem) {
+            string_array[i] = RedisModule_CreateStringFromLongLong(NULL, j);
+            string_array[i + 1] = RedisModule_CreateString(NULL, mem->block, BLOCK_SIZE);
+            mem = mem->next;
+            i += 2;
+            j++;
+        }
+        RedisModule_EmitAOF(aof, "mem.allocandwrite", "slv", key, o->size, string_array, array_size);
+        for (i = 0; i < array_size; i++) {
+            RedisModule_FreeString(NULL, string_array[i]);
+        }
+        RedisModule_Free(string_array);
+    } else {
+        RedisModule_EmitAOF(aof, "mem.allocandwrite", "sl", key, o->size);
+    }
+}
+
+void MemAllocFree(void *value) {
+    RedisModule_Free(value);
+}
+
+void MemAllocUnlink(RedisModuleString *key, const void *value) {
+    REDISMODULE_NOT_USED(key);
+    REDISMODULE_NOT_USED(value);
+
+    /* When unlink and unlink2 exist at the same time, we will only call unlink2. */
+    RedisModule_Assert(0);
+}
+
+void MemAllocUnlink2(RedisModuleKeyOptCtx *ctx, const void *value) {
+    MemAllocObject *o = (MemAllocObject *)value;
+
+    const RedisModuleString *key = RedisModule_GetKeyNameFromOptCtx(ctx);
+    int dbid = RedisModule_GetDbIdFromOptCtx(ctx);
+    
+    if (o->size) {
+        void *oldval;
+        RedisModule_DictDel(mem_pool[dbid], (RedisModuleString *)key, &oldval);
+        RedisModule_Assert(oldval != NULL);
+        MemBlockFree((struct MemBlock *)oldval);
+    }
+}
+
+void MemAllocDigest(RedisModuleDigest *md, void *value) {
+    MemAllocObject *o = (MemAllocObject *)value;
+    RedisModule_DigestAddLongLong(md, o->size);
+    RedisModule_DigestAddLongLong(md, o->used);
+    RedisModule_DigestAddLongLong(md, o->mask);
+
+    int dbid = RedisModule_GetDbIdFromDigest(md);
+    const RedisModuleString *key = RedisModule_GetKeyNameFromDigest(md);
+    
+    if (o->size) {
+        int nokey;
+        struct MemBlock *mem = (struct MemBlock *)RedisModule_DictGet(mem_pool[dbid], (RedisModuleString *)key, &nokey);
+        RedisModule_Assert(nokey == 0 && mem != NULL);
+
+        struct MemBlock *block = mem;
+        while (block) {
+            RedisModule_DigestAddStringBuffer(md, (const char *)block->block, BLOCK_SIZE);
+            block = block->next;
+        }
+    }
+}
+
+void *MemAllocCopy2(RedisModuleKeyOptCtx *ctx, const void *value) {
+    const MemAllocObject *old = value;
+    MemAllocObject *new = createMemAllocObject();
+    new->size = old->size;
+    new->used = old->used;
+    new->mask = old->mask;
+
+    int from_dbid = RedisModule_GetDbIdFromOptCtx(ctx);
+    int to_dbid = RedisModule_GetToDbIdFromOptCtx(ctx);
+    const RedisModuleString *fromkey = RedisModule_GetKeyNameFromOptCtx(ctx);
+    const RedisModuleString *tokey = RedisModule_GetToKeyNameFromOptCtx(ctx);
+
+    if (old->size) {
+        int nokey;
+        struct MemBlock *oldmem = (struct MemBlock *)RedisModule_DictGet(mem_pool[from_dbid], (RedisModuleString *)fromkey, &nokey);
+        RedisModule_Assert(nokey == 0 && oldmem != NULL);
+        struct MemBlock *newmem = MemBlockClone(oldmem);
+        RedisModule_Assert(newmem != NULL);
+        RedisModule_DictSet(mem_pool[to_dbid], (RedisModuleString *)tokey, newmem);
+    }   
+
+    return new;
+}
+
+size_t MemAllocMemUsage2(RedisModuleKeyOptCtx *ctx, const void *value, size_t sample_size) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(sample_size);
+    uint64_t size = 0;
+    MemAllocObject *o = (MemAllocObject *)value;
+
+    size += sizeof(*o);
+    size += o->size * sizeof(struct MemBlock);
+
+    return size;
+}
+
+size_t MemAllocMemFreeEffort2(RedisModuleKeyOptCtx *ctx, const void *value) {
+    REDISMODULE_NOT_USED(ctx);
+    MemAllocObject *o = (MemAllocObject *)value;
+    return o->size;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "datatype2", 1,REDISMODULE_APIVER_1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    RedisModuleTypeMethods tm = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = MemAllocRdbLoad,
+        .rdb_save = MemAllocRdbSave,
+        .aof_rewrite = MemAllocAofRewrite,
+        .free = MemAllocFree,
+        .digest = MemAllocDigest,
+        .unlink = MemAllocUnlink,
+        // .defrag = MemAllocDefrag, // Tested in defragtest.c
+        .unlink2 = MemAllocUnlink2,
+        .copy2 = MemAllocCopy2,
+        .mem_usage2 = MemAllocMemUsage2,
+        .free_effort2 = MemAllocMemFreeEffort2,
+    };
+
+    MemAllocType = RedisModule_CreateDataType(ctx, "mem_alloc", 0, &tm);
+    if (MemAllocType == NULL) {
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "mem.alloc", MemAlloc_RedisCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "mem.free", MemFree_RedisCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "mem.write", MemWrite_RedisCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "mem.read", MemRead_RedisCommand, "readonly", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "mem.usage", MemUsage_RedisCommand, "readonly", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    /* used for internal aof rewrite */
+    if (RedisModule_CreateCommand(ctx, "mem.allocandwrite", MemAllocAndWrite_RedisCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    for(int i = 0; i < MAX_DB; i++){
+        mem_pool[i] = RedisModule_CreateDict(NULL);
+    }
+
+    RedisModule_SubscribeToServerEvent(ctx, RedisModuleEvent_FlushDB, flushdbCallback);
+    RedisModule_SubscribeToServerEvent(ctx, RedisModuleEvent_SwapDB, swapDbCallback);
+  
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/defragtest.c b/tests/modules/defragtest.c
new file mode 100644
index 0000000..6a02a05
--- /dev/null
+++ b/tests/modules/defragtest.c
@@ -0,0 +1,235 @@
+/* A module that implements defrag callback mechanisms.
+ */
+
+#include "redismodule.h"
+#include <stdlib.h>
+
+static RedisModuleType *FragType;
+
+struct FragObject {
+    unsigned long len;
+    void **values;
+    int maxstep;
+};
+
+/* Make sure we get the expected cursor */
+unsigned long int last_set_cursor = 0;
+
+unsigned long int datatype_attempts = 0;
+unsigned long int datatype_defragged = 0;
+unsigned long int datatype_resumes = 0;
+unsigned long int datatype_wrong_cursor = 0;
+unsigned long int global_attempts = 0;
+unsigned long int global_defragged = 0;
+
+int global_strings_len = 0;
+RedisModuleString **global_strings = NULL;
+
+static void createGlobalStrings(RedisModuleCtx *ctx, int count)
+{
+    global_strings_len = count;
+    global_strings = RedisModule_Alloc(sizeof(RedisModuleString *) * count);
+
+    for (int i = 0; i < count; i++) {
+        global_strings[i] = RedisModule_CreateStringFromLongLong(ctx, i);
+    }
+}
+
+static void defragGlobalStrings(RedisModuleDefragCtx *ctx)
+{
+    for (int i = 0; i < global_strings_len; i++) {
+        RedisModuleString *new = RedisModule_DefragRedisModuleString(ctx, global_strings[i]);
+        global_attempts++;
+        if (new != NULL) {
+            global_strings[i] = new;
+            global_defragged++;
+        }
+    }
+}
+
+static void FragInfo(RedisModuleInfoCtx *ctx, int for_crash_report) {
+    REDISMODULE_NOT_USED(for_crash_report);
+
+    RedisModule_InfoAddSection(ctx, "stats");
+    RedisModule_InfoAddFieldLongLong(ctx, "datatype_attempts", datatype_attempts);
+    RedisModule_InfoAddFieldLongLong(ctx, "datatype_defragged", datatype_defragged);
+    RedisModule_InfoAddFieldLongLong(ctx, "datatype_resumes", datatype_resumes);
+    RedisModule_InfoAddFieldLongLong(ctx, "datatype_wrong_cursor", datatype_wrong_cursor);
+    RedisModule_InfoAddFieldLongLong(ctx, "global_attempts", global_attempts);
+    RedisModule_InfoAddFieldLongLong(ctx, "global_defragged", global_defragged);
+}
+
+struct FragObject *createFragObject(unsigned long len, unsigned long size, int maxstep) {
+    struct FragObject *o = RedisModule_Alloc(sizeof(*o));
+    o->len = len;
+    o->values = RedisModule_Alloc(sizeof(RedisModuleString*) * len);
+    o->maxstep = maxstep;
+
+    for (unsigned long i = 0; i < len; i++) {
+        o->values[i] = RedisModule_Calloc(1, size);
+    }
+
+    return o;
+}
+
+/* FRAG.RESETSTATS */
+static int fragResetStatsCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    datatype_attempts = 0;
+    datatype_defragged = 0;
+    datatype_resumes = 0;
+    datatype_wrong_cursor = 0;
+    global_attempts = 0;
+    global_defragged = 0;
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+/* FRAG.CREATE key len size maxstep */
+static int fragCreateCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 5)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx,argv[1],
+                                              REDISMODULE_READ|REDISMODULE_WRITE);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY)
+    {
+        return RedisModule_ReplyWithError(ctx, "ERR key exists");
+    }
+
+    long long len;
+    if ((RedisModule_StringToLongLong(argv[2], &len) != REDISMODULE_OK)) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid len");
+    }
+
+    long long size;
+    if ((RedisModule_StringToLongLong(argv[3], &size) != REDISMODULE_OK)) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid size");
+    }
+
+    long long maxstep;
+    if ((RedisModule_StringToLongLong(argv[4], &maxstep) != REDISMODULE_OK)) {
+        return RedisModule_ReplyWithError(ctx, "ERR invalid maxstep");
+    }
+
+    struct FragObject *o = createFragObject(len, size, maxstep);
+    RedisModule_ModuleTypeSetValue(key, FragType, o);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    RedisModule_CloseKey(key);
+
+    return REDISMODULE_OK;
+}
+
+void FragFree(void *value) {
+    struct FragObject *o = value;
+
+    for (unsigned long i = 0; i < o->len; i++)
+        RedisModule_Free(o->values[i]);
+    RedisModule_Free(o->values);
+    RedisModule_Free(o);
+}
+
+size_t FragFreeEffort(RedisModuleString *key, const void *value) {
+    REDISMODULE_NOT_USED(key);
+
+    const struct FragObject *o = value;
+    return o->len;
+}
+
+int FragDefrag(RedisModuleDefragCtx *ctx, RedisModuleString *key, void **value) {
+    REDISMODULE_NOT_USED(key);
+    unsigned long i = 0;
+    int steps = 0;
+
+    int dbid = RedisModule_GetDbIdFromDefragCtx(ctx);
+    RedisModule_Assert(dbid != -1);
+
+    /* Attempt to get cursor, validate it's what we're exepcting */
+    if (RedisModule_DefragCursorGet(ctx, &i) == REDISMODULE_OK) {
+        if (i > 0) datatype_resumes++;
+
+        /* Validate we're expecting this cursor */
+        if (i != last_set_cursor) datatype_wrong_cursor++;
+    } else {
+        if (last_set_cursor != 0) datatype_wrong_cursor++;
+    }
+
+    /* Attempt to defrag the object itself */
+    datatype_attempts++;
+    struct FragObject *o = RedisModule_DefragAlloc(ctx, *value);
+    if (o == NULL) {
+        /* Not defragged */
+        o = *value;
+    } else {
+        /* Defragged */
+        *value = o;
+        datatype_defragged++;
+    }
+
+    /* Deep defrag now */
+    for (; i < o->len; i++) {
+        datatype_attempts++;
+        void *new = RedisModule_DefragAlloc(ctx, o->values[i]);
+        if (new) {
+            o->values[i] = new;
+            datatype_defragged++;
+        }
+
+        if ((o->maxstep && ++steps > o->maxstep) ||
+            ((i % 64 == 0) && RedisModule_DefragShouldStop(ctx)))
+        {
+            RedisModule_DefragCursorSet(ctx, i);
+            last_set_cursor = i;
+            return 1;
+        }
+    }
+
+    last_set_cursor = 0;
+    return 0;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "defragtest", 1, REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_GetTypeMethodVersion() < REDISMODULE_TYPE_METHOD_VERSION) {
+        return REDISMODULE_ERR;
+    }
+
+    long long glen;
+    if (argc != 1 || RedisModule_StringToLongLong(argv[0], &glen) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    createGlobalStrings(ctx, glen);
+
+    RedisModuleTypeMethods tm = {
+            .version = REDISMODULE_TYPE_METHOD_VERSION,
+            .free = FragFree,
+            .free_effort = FragFreeEffort,
+            .defrag = FragDefrag
+    };
+
+    FragType = RedisModule_CreateDataType(ctx, "frag_type", 0, &tm);
+    if (FragType == NULL) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "frag.create",
+                                  fragCreateCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "frag.resetstats",
+                                  fragResetStatsCommand, "write deny-oom", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModule_RegisterInfoFunc(ctx, FragInfo);
+    RedisModule_RegisterDefragFunc(ctx, defragGlobalStrings);
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/eventloop.c b/tests/modules/eventloop.c
new file mode 100644
index 0000000..c0cfdf0
--- /dev/null
+++ b/tests/modules/eventloop.c
@@ -0,0 +1,276 @@
+/* This module contains four tests :
+ * 1- test.sanity    : Basic tests for argument validation mostly.
+ * 2- test.sendbytes : Creates a pipe and registers its fds to the event loop,
+ *                     one end of the pipe for read events and the other end for
+ *                     the write events. On writable event, data is written. On
+ *                     readable event data is read. Repeated until all data is
+ *                     received.
+ * 3- test.iteration : A test for BEFORE_SLEEP and AFTER_SLEEP callbacks.
+ *                     Counters are incremented each time these events are
+ *                     fired. They should be equal and increment monotonically.
+ * 4- test.oneshot   : Test for oneshot API
+ */
+
+#include "redismodule.h"
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <memory.h>
+#include <errno.h>
+
+int fds[2];
+long long buf_size;
+char *src;
+long long src_offset;
+char *dst;
+long long dst_offset;
+
+RedisModuleBlockedClient *bc;
+RedisModuleCtx *reply_ctx;
+
+void onReadable(int fd, void *user_data, int mask) {
+    REDISMODULE_NOT_USED(mask);
+
+    RedisModule_Assert(strcmp(user_data, "userdataread") == 0);
+
+    while (1) {
+        int rd = read(fd, dst + dst_offset, buf_size - dst_offset);
+        if (rd <= 0)
+            return;
+        dst_offset += rd;
+
+        /* Received all bytes */
+        if (dst_offset == buf_size) {
+            if (memcmp(src, dst, buf_size) == 0)
+                RedisModule_ReplyWithSimpleString(reply_ctx, "OK");
+            else
+                RedisModule_ReplyWithError(reply_ctx, "ERR bytes mismatch");
+
+            RedisModule_EventLoopDel(fds[0], REDISMODULE_EVENTLOOP_READABLE);
+            RedisModule_EventLoopDel(fds[1], REDISMODULE_EVENTLOOP_WRITABLE);
+            RedisModule_Free(src);
+            RedisModule_Free(dst);
+            close(fds[0]);
+            close(fds[1]);
+
+            RedisModule_FreeThreadSafeContext(reply_ctx);
+            RedisModule_UnblockClient(bc, NULL);
+            return;
+        }
+    };
+}
+
+void onWritable(int fd, void *user_data, int mask) {
+    REDISMODULE_NOT_USED(user_data);
+    REDISMODULE_NOT_USED(mask);
+
+    RedisModule_Assert(strcmp(user_data, "userdatawrite") == 0);
+
+    while (1) {
+        /* Check if we sent all data */
+        if (src_offset >= buf_size)
+            return;
+        int written = write(fd, src + src_offset, buf_size - src_offset);
+        if (written <= 0) {
+            return;
+        }
+
+        src_offset += written;
+    };
+}
+
+/* Create a pipe(), register pipe fds to the event loop and send/receive data
+ * using them. */
+int sendbytes(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    if (RedisModule_StringToLongLong(argv[1], &buf_size) != REDISMODULE_OK ||
+        buf_size == 0) {
+        RedisModule_ReplyWithError(ctx, "Invalid integer value");
+        return REDISMODULE_OK;
+    }
+
+    bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+    reply_ctx = RedisModule_GetThreadSafeContext(bc);
+
+    /* Allocate source buffer and write some random data */
+    src = RedisModule_Calloc(1,buf_size);
+    src_offset = 0;
+    memset(src, rand() % 0xFF, buf_size);
+    memcpy(src, "randomtestdata", strlen("randomtestdata"));
+
+    dst = RedisModule_Calloc(1,buf_size);
+    dst_offset = 0;
+
+    /* Create a pipe and register it to the event loop. */
+    if (pipe(fds) < 0) return REDISMODULE_ERR;
+    if (fcntl(fds[0], F_SETFL, O_NONBLOCK) < 0) return REDISMODULE_ERR;
+    if (fcntl(fds[1], F_SETFL, O_NONBLOCK) < 0) return REDISMODULE_ERR;
+
+    if (RedisModule_EventLoopAdd(fds[0], REDISMODULE_EVENTLOOP_READABLE,
+        onReadable, "userdataread") != REDISMODULE_OK) return REDISMODULE_ERR;
+    if (RedisModule_EventLoopAdd(fds[1], REDISMODULE_EVENTLOOP_WRITABLE,
+        onWritable, "userdatawrite") != REDISMODULE_OK) return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
+
+int sanity(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (pipe(fds) < 0) return REDISMODULE_ERR;
+
+    if (RedisModule_EventLoopAdd(fds[0], 9999999, onReadable, NULL)
+        == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, "ERR non-existing event type should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(-1, REDISMODULE_EVENTLOOP_READABLE, onReadable, NULL)
+        == REDISMODULE_OK || errno != ERANGE) {
+        RedisModule_ReplyWithError(ctx, "ERR out of range fd should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(99999999, REDISMODULE_EVENTLOOP_READABLE, onReadable, NULL)
+        == REDISMODULE_OK || errno != ERANGE) {
+        RedisModule_ReplyWithError(ctx, "ERR out of range fd should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(fds[0], REDISMODULE_EVENTLOOP_READABLE, NULL, NULL)
+        == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, "ERR null callback should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(fds[0], 9999999, onReadable, NULL)
+        == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, "ERR non-existing event type should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopDel(fds[0], REDISMODULE_EVENTLOOP_READABLE)
+        != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, "ERR del on non-registered fd should not fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopDel(fds[0], 9999999) == REDISMODULE_OK ||
+        errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, "ERR non-existing event type should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopDel(-1, REDISMODULE_EVENTLOOP_READABLE)
+        == REDISMODULE_OK || errno != ERANGE) {
+        RedisModule_ReplyWithError(ctx, "ERR out of range fd should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopDel(99999999, REDISMODULE_EVENTLOOP_READABLE)
+        == REDISMODULE_OK || errno != ERANGE) {
+        RedisModule_ReplyWithError(ctx, "ERR out of range fd should fail");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(fds[0], REDISMODULE_EVENTLOOP_READABLE, onReadable, NULL)
+        != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, "ERR Add failed");
+        goto out;
+    }
+    if (RedisModule_EventLoopAdd(fds[0], REDISMODULE_EVENTLOOP_READABLE, onReadable, NULL)
+        != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, "ERR Adding same fd twice failed");
+        goto out;
+    }
+    if (RedisModule_EventLoopDel(fds[0], REDISMODULE_EVENTLOOP_READABLE)
+        != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, "ERR Del failed");
+        goto out;
+    }
+    if (RedisModule_EventLoopAddOneShot(NULL, NULL) == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, "ERR null callback should fail");
+        goto out;
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+out:
+    close(fds[0]);
+    close(fds[1]);
+    return REDISMODULE_OK;
+}
+
+static long long beforeSleepCount;
+static long long afterSleepCount;
+
+int iteration(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    /* On each event loop iteration, eventloopCallback() is called. We increment
+     * beforeSleepCount and afterSleepCount, so these two should be equal.
+     * We reply with iteration count, caller can test if iteration count
+     * increments monotonically */
+    RedisModule_Assert(beforeSleepCount == afterSleepCount);
+    RedisModule_ReplyWithLongLong(ctx, beforeSleepCount);
+    return REDISMODULE_OK;
+}
+
+void oneshotCallback(void* arg)
+{
+    RedisModule_Assert(strcmp(arg, "userdata") == 0);
+    RedisModule_ReplyWithSimpleString(reply_ctx, "OK");
+    RedisModule_FreeThreadSafeContext(reply_ctx);
+    RedisModule_UnblockClient(bc, NULL);
+}
+
+int oneshot(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+    reply_ctx = RedisModule_GetThreadSafeContext(bc);
+
+    if (RedisModule_EventLoopAddOneShot(oneshotCallback, "userdata") != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "ERR oneshot failed");
+        RedisModule_FreeThreadSafeContext(reply_ctx);
+        RedisModule_UnblockClient(bc, NULL);
+    }
+    return REDISMODULE_OK;
+}
+
+void eventloopCallback(struct RedisModuleCtx *ctx, RedisModuleEvent eid, uint64_t subevent, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(eid);
+    REDISMODULE_NOT_USED(subevent);
+    REDISMODULE_NOT_USED(data);
+
+    RedisModule_Assert(eid.id == REDISMODULE_EVENT_EVENTLOOP);
+    if (subevent == REDISMODULE_SUBEVENT_EVENTLOOP_BEFORE_SLEEP)
+        beforeSleepCount++;
+    else if (subevent == REDISMODULE_SUBEVENT_EVENTLOOP_AFTER_SLEEP)
+        afterSleepCount++;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"eventloop",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* Test basics. */
+    if (RedisModule_CreateCommand(ctx, "test.sanity", sanity, "", 0, 0, 0)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* Register a command to create a pipe() and send data through it by using
+     * event loop API. */
+    if (RedisModule_CreateCommand(ctx, "test.sendbytes", sendbytes, "", 0, 0, 0)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* Register a command to return event loop iteration count. */
+    if (RedisModule_CreateCommand(ctx, "test.iteration", iteration, "", 0, 0, 0)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "test.oneshot", oneshot, "", 0, 0, 0)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_SubscribeToServerEvent(ctx, RedisModuleEvent_EventLoop,
+        eventloopCallback) != REDISMODULE_OK) return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/fork.c b/tests/modules/fork.c
new file mode 100644
index 0000000..d7a0d15
--- /dev/null
+++ b/tests/modules/fork.c
@@ -0,0 +1,96 @@
+
+/* define macros for having usleep */
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE
+
+#include "redismodule.h"
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+
+#define UNUSED(V) ((void) V)
+
+int child_pid = -1;
+int exitted_with_code = -1;
+
+void done_handler(int exitcode, int bysignal, void *user_data) {
+    child_pid = -1;
+    exitted_with_code = exitcode;
+    assert(user_data==(void*)0xdeadbeef);
+    UNUSED(bysignal);
+}
+
+int fork_create(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    long long code_to_exit_with;
+    long long usleep_us;
+    if (argc != 3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    if(!RMAPI_FUNC_SUPPORTED(RedisModule_Fork)){
+        RedisModule_ReplyWithError(ctx, "Fork api is not supported in the current redis version");
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_StringToLongLong(argv[1], &code_to_exit_with);
+    RedisModule_StringToLongLong(argv[2], &usleep_us);
+    exitted_with_code = -1;
+    int fork_child_pid = RedisModule_Fork(done_handler, (void*)0xdeadbeef);
+    if (fork_child_pid < 0) {
+        RedisModule_ReplyWithError(ctx, "Fork failed");
+        return REDISMODULE_OK;
+    } else if (fork_child_pid > 0) {
+        /* parent */
+        child_pid = fork_child_pid;
+        RedisModule_ReplyWithLongLong(ctx, child_pid);
+        return REDISMODULE_OK;
+    }
+
+    /* child */
+    RedisModule_Log(ctx, "notice", "fork child started");
+    usleep(usleep_us);
+    RedisModule_Log(ctx, "notice", "fork child exiting");
+    RedisModule_ExitFromChild(code_to_exit_with);
+    /* unreachable */
+    return 0;
+}
+
+int fork_exitcode(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModule_ReplyWithLongLong(ctx, exitted_with_code);
+    return REDISMODULE_OK;
+}
+
+int fork_kill(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    UNUSED(argv);
+    UNUSED(argc);
+    if (RedisModule_KillForkChild(child_pid) != REDISMODULE_OK)
+        RedisModule_ReplyWithError(ctx, "KillForkChild failed");
+    else
+        RedisModule_ReplyWithLongLong(ctx, 1);
+    child_pid = -1;
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    if (RedisModule_Init(ctx,"fork",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fork.create", fork_create,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fork.exitcode", fork_exitcode,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"fork.kill", fork_kill,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/getchannels.c b/tests/modules/getchannels.c
new file mode 100644
index 0000000..330531d
--- /dev/null
+++ b/tests/modules/getchannels.c
@@ -0,0 +1,69 @@
+#include "redismodule.h"
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+#include <errno.h>
+
+/* A sample with declarable channels, that are used to validate against ACLs */
+int getChannels_subscribe(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if ((argc - 1) % 3 != 0) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    char *err = NULL;
+    
+    /* getchannels.command [[subscribe|unsubscribe|publish] [pattern|literal] <channel> ...]
+     * This command marks the given channel is accessed based on the
+     * provided modifiers. */
+    for (int i = 1; i < argc; i += 3) {
+        const char *operation = RedisModule_StringPtrLen(argv[i], NULL);
+        const char *type = RedisModule_StringPtrLen(argv[i+1], NULL);
+        int flags = 0;
+
+        if (!strcasecmp(operation, "subscribe")) {
+            flags |= REDISMODULE_CMD_CHANNEL_SUBSCRIBE;
+        } else if (!strcasecmp(operation, "unsubscribe")) {
+            flags |= REDISMODULE_CMD_CHANNEL_UNSUBSCRIBE;
+        } else if (!strcasecmp(operation, "publish")) {
+            flags |= REDISMODULE_CMD_CHANNEL_PUBLISH;
+        } else {
+            err = "Invalid channel operation";
+            break;
+        }
+
+        if (!strcasecmp(type, "literal")) {
+            /* No op */
+        } else if (!strcasecmp(type, "pattern")) {
+            flags |= REDISMODULE_CMD_CHANNEL_PATTERN;
+        } else {
+            err = "Invalid channel type";
+            break;
+        }
+        if (RedisModule_IsChannelsPositionRequest(ctx)) {
+            RedisModule_ChannelAtPosWithFlags(ctx, i+2, flags);
+        }
+    }
+
+    if (!RedisModule_IsChannelsPositionRequest(ctx)) {
+        if (err) {
+            RedisModule_ReplyWithError(ctx, err);
+        } else {
+            /* Normal implementation would go here, but for tests just return okay */
+            RedisModule_ReplyWithSimpleString(ctx, "OK");
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "getchannels", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "getchannels.command", getChannels_subscribe, "getchannels-api", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/getkeys.c b/tests/modules/getkeys.c
new file mode 100644
index 0000000..cee3b3e
--- /dev/null
+++ b/tests/modules/getkeys.c
@@ -0,0 +1,178 @@
+
+#include "redismodule.h"
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+#include <errno.h>
+
+#define UNUSED(V) ((void) V)
+
+/* A sample movable keys command that returns a list of all
+ * arguments that follow a KEY argument, i.e.
+ */
+int getkeys_command(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    int i;
+    int count = 0;
+
+    /* Handle getkeys-api introspection */
+    if (RedisModule_IsKeysPositionRequest(ctx)) {
+        for (i = 0; i < argc; i++) {
+            size_t len;
+            const char *str = RedisModule_StringPtrLen(argv[i], &len);
+
+            if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc)
+                RedisModule_KeyAtPos(ctx, i + 1);
+        }
+
+        return REDISMODULE_OK;
+    }
+
+    /* Handle real command invocation */
+    RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
+    for (i = 0; i < argc; i++) {
+        size_t len;
+        const char *str = RedisModule_StringPtrLen(argv[i], &len);
+
+        if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc) {
+            RedisModule_ReplyWithString(ctx, argv[i+1]);
+            count++;
+        }
+    }
+    RedisModule_ReplySetArrayLength(ctx, count);
+
+    return REDISMODULE_OK;
+}
+
+int getkeys_command_with_flags(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    int i;
+    int count = 0;
+
+    /* Handle getkeys-api introspection */
+    if (RedisModule_IsKeysPositionRequest(ctx)) {
+        for (i = 0; i < argc; i++) {
+            size_t len;
+            const char *str = RedisModule_StringPtrLen(argv[i], &len);
+
+            if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc)
+                RedisModule_KeyAtPosWithFlags(ctx, i + 1, REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS);
+        }
+
+        return REDISMODULE_OK;
+    }
+
+    /* Handle real command invocation */
+    RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
+    for (i = 0; i < argc; i++) {
+        size_t len;
+        const char *str = RedisModule_StringPtrLen(argv[i], &len);
+
+        if (len == 3 && !strncasecmp(str, "key", 3) && i + 1 < argc) {
+            RedisModule_ReplyWithString(ctx, argv[i+1]);
+            count++;
+        }
+    }
+    RedisModule_ReplySetArrayLength(ctx, count);
+
+    return REDISMODULE_OK;
+}
+
+int getkeys_fixed(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    int i;
+
+    RedisModule_ReplyWithArray(ctx, argc - 1);
+    for (i = 1; i < argc; i++) {
+        RedisModule_ReplyWithString(ctx, argv[i]);
+    }
+    return REDISMODULE_OK;
+}
+
+/* Introspect a command using RM_GetCommandKeys() and returns the list
+ * of keys. Essentially this is COMMAND GETKEYS implemented in a module.
+ * INTROSPECT <with-flags> <cmd> <args>
+ */
+int getkeys_introspect(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    long long with_flags = 0;
+
+    if (argc < 4) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    if (RedisModule_StringToLongLong(argv[1],&with_flags) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx,"ERR invalid integer");
+
+    int num_keys, *keyflags = NULL;
+    int *keyidx = RedisModule_GetCommandKeysWithFlags(ctx, &argv[2], argc - 2, &num_keys, with_flags ? &keyflags : NULL);
+
+    if (!keyidx) {
+        if (!errno)
+            RedisModule_ReplyWithEmptyArray(ctx);
+        else {
+            char err[100];
+            switch (errno) {
+                case ENOENT:
+                    RedisModule_ReplyWithError(ctx, "ERR ENOENT");
+                    break;
+                case EINVAL:
+                    RedisModule_ReplyWithError(ctx, "ERR EINVAL");
+                    break;
+                default:
+                    snprintf(err, sizeof(err) - 1, "ERR errno=%d", errno);
+                    RedisModule_ReplyWithError(ctx, err);
+                    break;
+            }
+        }
+    } else {
+        int i;
+
+        RedisModule_ReplyWithArray(ctx, num_keys);
+        for (i = 0; i < num_keys; i++) {
+            if (!with_flags) {
+                RedisModule_ReplyWithString(ctx, argv[2 + keyidx[i]]);
+                continue;
+            }
+            RedisModule_ReplyWithArray(ctx, 2);
+            RedisModule_ReplyWithString(ctx, argv[2 + keyidx[i]]);
+            char* sflags = "";
+            if (keyflags[i] & REDISMODULE_CMD_KEY_RO)
+                sflags = "RO";
+            else if (keyflags[i] & REDISMODULE_CMD_KEY_RW)
+                sflags = "RW";
+            else if (keyflags[i] & REDISMODULE_CMD_KEY_OW)
+                sflags = "OW";
+            else if (keyflags[i] & REDISMODULE_CMD_KEY_RM)
+                sflags = "RM";
+            RedisModule_ReplyWithCString(ctx, sflags);
+        }
+
+        RedisModule_Free(keyidx);
+        RedisModule_Free(keyflags);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    if (RedisModule_Init(ctx,"getkeys",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"getkeys.command", getkeys_command,"getkeys-api",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"getkeys.command_with_flags", getkeys_command_with_flags,"getkeys-api",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"getkeys.fixed", getkeys_fixed,"",2,4,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"getkeys.introspect", getkeys_introspect,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/hash.c b/tests/modules/hash.c
new file mode 100644
index 0000000..001a34e
--- /dev/null
+++ b/tests/modules/hash.c
@@ -0,0 +1,90 @@
+#include "redismodule.h"
+#include <strings.h>
+#include <errno.h>
+#include <stdlib.h>
+
+/* If a string is ":deleted:", the special value for deleted hash fields is
+ * returned; otherwise the input string is returned. */
+static RedisModuleString *value_or_delete(RedisModuleString *s) {
+    if (!strcasecmp(RedisModule_StringPtrLen(s, NULL), ":delete:"))
+        return REDISMODULE_HASH_DELETE;
+    else
+        return s;
+}
+
+/* HASH.SET key flags field1 value1 [field2 value2 ..]
+ *
+ * Sets 1-4 fields. Returns the same as RedisModule_HashSet().
+ * Flags is a string of "nxa" where n = NX, x = XX, a = COUNT_ALL.
+ * To delete a field, use the value ":delete:".
+ */
+int hash_set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 5 || argc % 2 == 0 || argc > 11)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModule_AutoMemory(ctx);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+
+    size_t flags_len;
+    const char *flags_str = RedisModule_StringPtrLen(argv[2], &flags_len);
+    int flags = REDISMODULE_HASH_NONE;
+    for (size_t i = 0; i < flags_len; i++) {
+        switch (flags_str[i]) {
+        case 'n': flags |= REDISMODULE_HASH_NX; break;
+        case 'x': flags |= REDISMODULE_HASH_XX; break;
+        case 'a': flags |= REDISMODULE_HASH_COUNT_ALL; break;
+        }
+    }
+
+    /* Test some varargs. (In real-world, use a loop and set one at a time.) */
+    int result;
+    errno = 0;
+    if (argc == 5) {
+        result = RedisModule_HashSet(key, flags,
+                                     argv[3], value_or_delete(argv[4]),
+                                     NULL);
+    } else if (argc == 7) {
+        result = RedisModule_HashSet(key, flags,
+                                     argv[3], value_or_delete(argv[4]),
+                                     argv[5], value_or_delete(argv[6]),
+                                     NULL);
+    } else if (argc == 9) {
+        result = RedisModule_HashSet(key, flags,
+                                     argv[3], value_or_delete(argv[4]),
+                                     argv[5], value_or_delete(argv[6]),
+                                     argv[7], value_or_delete(argv[8]),
+                                     NULL);
+    } else if (argc == 11) {
+        result = RedisModule_HashSet(key, flags,
+                                     argv[3], value_or_delete(argv[4]),
+                                     argv[5], value_or_delete(argv[6]),
+                                     argv[7], value_or_delete(argv[8]),
+                                     argv[9], value_or_delete(argv[10]),
+                                     NULL);
+    } else {
+        return RedisModule_ReplyWithError(ctx, "ERR too many fields");
+    }
+
+    /* Check errno */
+    if (result == 0) {
+        if (errno == ENOTSUP)
+            return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+        else
+            RedisModule_Assert(errno == ENOENT);
+    }
+
+    return RedisModule_ReplyWithLongLong(ctx, result);
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "hash", 1, REDISMODULE_APIVER_1) ==
+        REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "hash.set", hash_set, "write",
+                                  1, 1, 1) == REDISMODULE_OK) {
+        return REDISMODULE_OK;
+    } else {
+        return REDISMODULE_ERR;
+    }
+}
diff --git a/tests/modules/hooks.c b/tests/modules/hooks.c
new file mode 100644
index 0000000..fc357d1
--- /dev/null
+++ b/tests/modules/hooks.c
@@ -0,0 +1,516 @@
+/* This module is used to test the server events hooks API.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2019, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "redismodule.h"
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+
+/* We need to store events to be able to test and see what we got, and we can't
+ * store them in the key-space since that would mess up rdb loading (duplicates)
+ * and be lost of flushdb. */
+RedisModuleDict *event_log = NULL;
+/* stores all the keys on which we got 'removed' event */
+RedisModuleDict *removed_event_log = NULL;
+/* stores all the subevent on which we got 'removed' event */
+RedisModuleDict *removed_subevent_type = NULL;
+/* stores all the keys on which we got 'removed' event with expiry information */
+RedisModuleDict *removed_expiry_log = NULL;
+
+typedef struct EventElement {
+    long count;
+    RedisModuleString *last_val_string;
+    long last_val_int;
+} EventElement;
+
+void LogStringEvent(RedisModuleCtx *ctx, const char* keyname, const char* data) {
+    EventElement *event = RedisModule_DictGetC(event_log, (void*)keyname, strlen(keyname), NULL);
+    if (!event) {
+        event = RedisModule_Alloc(sizeof(EventElement));
+        memset(event, 0, sizeof(EventElement));
+        RedisModule_DictSetC(event_log, (void*)keyname, strlen(keyname), event);
+    }
+    if (event->last_val_string) RedisModule_FreeString(ctx, event->last_val_string);
+    event->last_val_string = RedisModule_CreateString(ctx, data, strlen(data));
+    event->count++;
+}
+
+void LogNumericEvent(RedisModuleCtx *ctx, const char* keyname, long data) {
+    REDISMODULE_NOT_USED(ctx);
+    EventElement *event = RedisModule_DictGetC(event_log, (void*)keyname, strlen(keyname), NULL);
+    if (!event) {
+        event = RedisModule_Alloc(sizeof(EventElement));
+        memset(event, 0, sizeof(EventElement));
+        RedisModule_DictSetC(event_log, (void*)keyname, strlen(keyname), event);
+    }
+    event->last_val_int = data;
+    event->count++;
+}
+
+void FreeEvent(RedisModuleCtx *ctx, EventElement *event) {
+    if (event->last_val_string)
+        RedisModule_FreeString(ctx, event->last_val_string);
+    RedisModule_Free(event);
+}
+
+int cmdEventCount(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    EventElement *event = RedisModule_DictGet(event_log, argv[1], NULL);
+    RedisModule_ReplyWithLongLong(ctx, event? event->count: 0);
+    return REDISMODULE_OK;
+}
+
+int cmdEventLast(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    EventElement *event = RedisModule_DictGet(event_log, argv[1], NULL);
+    if (event && event->last_val_string)
+        RedisModule_ReplyWithString(ctx, event->last_val_string);
+    else if (event)
+        RedisModule_ReplyWithLongLong(ctx, event->last_val_int);
+    else
+        RedisModule_ReplyWithNull(ctx);
+    return REDISMODULE_OK;
+}
+
+void clearEvents(RedisModuleCtx *ctx)
+{
+    RedisModuleString *key;
+    EventElement *event;
+    RedisModuleDictIter *iter = RedisModule_DictIteratorStart(event_log, "^", NULL);
+    while((key = RedisModule_DictNext(ctx, iter, (void**)&event)) != NULL) {
+        event->count = 0;
+        event->last_val_int = 0;
+        if (event->last_val_string) RedisModule_FreeString(ctx, event->last_val_string);
+        event->last_val_string = NULL;
+        RedisModule_DictDel(event_log, key, NULL);
+        RedisModule_Free(event);
+    }
+    RedisModule_DictIteratorStop(iter);
+}
+
+int cmdEventsClear(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argc);
+    REDISMODULE_NOT_USED(argv);
+    clearEvents(ctx);
+    return REDISMODULE_OK;
+}
+
+/* Client state change callback. */
+void clientChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+
+    RedisModuleClientInfo *ci = data;
+    char *keyname = (sub == REDISMODULE_SUBEVENT_CLIENT_CHANGE_CONNECTED) ?
+        "client-connected" : "client-disconnected";
+    LogNumericEvent(ctx, keyname, ci->id);
+}
+
+void flushdbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+
+    RedisModuleFlushInfo *fi = data;
+    char *keyname = (sub == REDISMODULE_SUBEVENT_FLUSHDB_START) ?
+        "flush-start" : "flush-end";
+    LogNumericEvent(ctx, keyname, fi->dbnum);
+}
+
+void roleChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    RedisModuleReplicationInfo *ri = data;
+    char *keyname = (sub == REDISMODULE_EVENT_REPLROLECHANGED_NOW_MASTER) ?
+        "role-master" : "role-replica";
+    LogStringEvent(ctx, keyname, ri->masterhost);
+}
+
+void replicationChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    char *keyname = (sub == REDISMODULE_SUBEVENT_REPLICA_CHANGE_ONLINE) ?
+        "replica-online" : "replica-offline";
+    LogNumericEvent(ctx, keyname, 0);
+}
+
+void rasterLinkChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    char *keyname = (sub == REDISMODULE_SUBEVENT_MASTER_LINK_UP) ?
+        "masterlink-up" : "masterlink-down";
+    LogNumericEvent(ctx, keyname, 0);
+}
+
+void persistenceCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    char *keyname = NULL;
+    switch (sub) {
+        case REDISMODULE_SUBEVENT_PERSISTENCE_RDB_START: keyname = "persistence-rdb-start"; break;
+        case REDISMODULE_SUBEVENT_PERSISTENCE_AOF_START: keyname = "persistence-aof-start"; break;
+        case REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_AOF_START: keyname = "persistence-syncaof-start"; break;
+        case REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_RDB_START: keyname = "persistence-syncrdb-start"; break;
+        case REDISMODULE_SUBEVENT_PERSISTENCE_ENDED: keyname = "persistence-end"; break;
+        case REDISMODULE_SUBEVENT_PERSISTENCE_FAILED: keyname = "persistence-failed"; break;
+    }
+    /* modifying the keyspace from the fork child is not an option, using log instead */
+    RedisModule_Log(ctx, "warning", "module-event-%s", keyname);
+    if (sub == REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_RDB_START ||
+        sub == REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_AOF_START) 
+    {
+        LogNumericEvent(ctx, keyname, 0);
+    }
+}
+
+void loadingCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    char *keyname = NULL;
+    switch (sub) {
+        case REDISMODULE_SUBEVENT_LOADING_RDB_START: keyname = "loading-rdb-start"; break;
+        case REDISMODULE_SUBEVENT_LOADING_AOF_START: keyname = "loading-aof-start"; break;
+        case REDISMODULE_SUBEVENT_LOADING_REPL_START: keyname = "loading-repl-start"; break;
+        case REDISMODULE_SUBEVENT_LOADING_ENDED: keyname = "loading-end"; break;
+        case REDISMODULE_SUBEVENT_LOADING_FAILED: keyname = "loading-failed"; break;
+    }
+    LogNumericEvent(ctx, keyname, 0);
+}
+
+void loadingProgressCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+
+    RedisModuleLoadingProgress *ei = data;
+    char *keyname = (sub == REDISMODULE_SUBEVENT_LOADING_PROGRESS_RDB) ?
+        "loading-progress-rdb" : "loading-progress-aof";
+    LogNumericEvent(ctx, keyname, ei->progress);
+}
+
+void shutdownCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+    REDISMODULE_NOT_USED(sub);
+
+    RedisModule_Log(ctx, "warning", "module-event-%s", "shutdown");
+}
+
+void cronLoopCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(sub);
+
+    RedisModuleCronLoop *ei = data;
+    LogNumericEvent(ctx, "cron-loop", ei->hz);
+}
+
+void moduleChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+
+    RedisModuleModuleChange *ei = data;
+    char *keyname = (sub == REDISMODULE_SUBEVENT_MODULE_LOADED) ?
+        "module-loaded" : "module-unloaded";
+    LogStringEvent(ctx, keyname, ei->module_name);
+}
+
+void swapDbCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(sub);
+
+    RedisModuleSwapDbInfo *ei = data;
+    LogNumericEvent(ctx, "swapdb-first", ei->dbnum_first);
+    LogNumericEvent(ctx, "swapdb-second", ei->dbnum_second);
+}
+
+void configChangeCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    if (sub != REDISMODULE_SUBEVENT_CONFIG_CHANGE) {
+        return;
+    }
+
+    RedisModuleConfigChangeV1 *ei = data;
+    LogNumericEvent(ctx, "config-change-count", ei->num_changes);
+    LogStringEvent(ctx, "config-change-first", ei->config_names[0]);
+}
+
+void keyInfoCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+
+    RedisModuleKeyInfoV1 *ei = data;
+    RedisModuleKey *kp = ei->key;
+    RedisModuleString *key = (RedisModuleString *) RedisModule_GetKeyNameFromModuleKey(kp);
+    const char *keyname = RedisModule_StringPtrLen(key, NULL);
+    RedisModuleString *event_keyname = RedisModule_CreateStringPrintf(ctx, "key-info-%s", keyname);
+    LogStringEvent(ctx, RedisModule_StringPtrLen(event_keyname, NULL), keyname);
+    RedisModule_FreeString(ctx, event_keyname);
+
+    /* Despite getting a key object from the callback, we also try to re-open it
+     * to make sure the callback is called before it is actually removed from the keyspace. */
+    RedisModuleKey *kp_open = RedisModule_OpenKey(ctx, key, REDISMODULE_READ);
+    assert(RedisModule_ValueLength(kp) == RedisModule_ValueLength(kp_open));
+    RedisModule_CloseKey(kp_open);
+
+    /* We also try to RM_Call a command that accesses that key, also to make sure it's still in the keyspace. */
+    char *size_command = NULL;
+    int key_type = RedisModule_KeyType(kp);
+    if (key_type == REDISMODULE_KEYTYPE_STRING) {
+        size_command = "STRLEN";
+    } else if (key_type == REDISMODULE_KEYTYPE_LIST) {
+        size_command = "LLEN";
+    } else if (key_type == REDISMODULE_KEYTYPE_HASH) {
+        size_command = "HLEN";
+    } else if (key_type == REDISMODULE_KEYTYPE_SET) {
+        size_command = "SCARD";
+    } else if (key_type == REDISMODULE_KEYTYPE_ZSET) {
+        size_command = "ZCARD";
+    } else if (key_type == REDISMODULE_KEYTYPE_STREAM) {
+        size_command = "XLEN";
+    }
+    if (size_command != NULL) {
+        RedisModuleCallReply *reply = RedisModule_Call(ctx, size_command, "s", key);
+        assert(reply != NULL);
+        assert(RedisModule_ValueLength(kp) == (size_t) RedisModule_CallReplyInteger(reply));
+        RedisModule_FreeCallReply(reply);
+    }
+
+    /* Now use the key object we got from the callback for various validations. */
+    RedisModuleString *prev = RedisModule_DictGetC(removed_event_log, (void*)keyname, strlen(keyname), NULL);
+    /* We keep object length */
+    RedisModuleString *v = RedisModule_CreateStringPrintf(ctx, "%zd", RedisModule_ValueLength(kp));
+    /* For string type, we keep value instead of length */
+    if (RedisModule_KeyType(kp) == REDISMODULE_KEYTYPE_STRING) {
+        RedisModule_FreeString(ctx, v);
+        size_t len;
+        /* We need to access the string value with RedisModule_StringDMA.
+         * RedisModule_StringDMA may call dbUnshareStringValue to free the origin object,
+         * so we also can test it. */
+        char *s = RedisModule_StringDMA(kp, &len, REDISMODULE_READ);
+        v = RedisModule_CreateString(ctx, s, len);
+    }
+    RedisModule_DictReplaceC(removed_event_log, (void*)keyname, strlen(keyname), v);
+    if (prev != NULL) {
+        RedisModule_FreeString(ctx, prev);
+    }
+
+    const char *subevent = "deleted";
+    if (sub == REDISMODULE_SUBEVENT_KEY_EXPIRED) {
+        subevent = "expired";
+    } else if (sub == REDISMODULE_SUBEVENT_KEY_EVICTED) {
+        subevent = "evicted";
+    } else if (sub == REDISMODULE_SUBEVENT_KEY_OVERWRITTEN) {
+        subevent = "overwritten";
+    }
+    RedisModule_DictReplaceC(removed_subevent_type, (void*)keyname, strlen(keyname), (void *)subevent);
+
+    RedisModuleString *prevexpire = RedisModule_DictGetC(removed_expiry_log, (void*)keyname, strlen(keyname), NULL);
+    RedisModuleString *expire = RedisModule_CreateStringPrintf(ctx, "%lld", RedisModule_GetAbsExpire(kp));
+    RedisModule_DictReplaceC(removed_expiry_log, (void*)keyname, strlen(keyname), (void *)expire);
+    if (prevexpire != NULL) {
+        RedisModule_FreeString(ctx, prevexpire);
+    }
+}
+
+static int cmdIsKeyRemoved(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc != 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char *key  = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleString *value = RedisModule_DictGetC(removed_event_log, (void*)key, strlen(key), NULL);
+
+    if (value == NULL) {
+        return RedisModule_ReplyWithError(ctx, "ERR Key was not removed");
+    }
+
+    const char *subevent = RedisModule_DictGetC(removed_subevent_type, (void*)key, strlen(key), NULL);
+    RedisModule_ReplyWithArray(ctx, 2);
+    RedisModule_ReplyWithString(ctx, value);
+    RedisModule_ReplyWithSimpleString(ctx, subevent);
+
+    return REDISMODULE_OK;
+}
+
+static int cmdKeyExpiry(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc != 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* key  = RedisModule_StringPtrLen(argv[1], NULL);
+    RedisModuleString *expire = RedisModule_DictGetC(removed_expiry_log, (void*)key, strlen(key), NULL);
+    if (expire == NULL) {
+        return RedisModule_ReplyWithError(ctx, "ERR Key was not removed");
+    }
+    RedisModule_ReplyWithString(ctx, expire);
+    return REDISMODULE_OK;
+}
+
+/* This function must be present on each Redis module. It is used in order to
+ * register the commands into the Redis server. */
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+#define VerifySubEventSupported(e, s) \
+    if (!RedisModule_IsSubEventSupported(e, s)) { \
+        return REDISMODULE_ERR; \
+    }
+
+    if (RedisModule_Init(ctx,"testhook",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* Example on how to check if a server sub event is supported */
+    if (!RedisModule_IsSubEventSupported(RedisModuleEvent_ReplicationRoleChanged, REDISMODULE_EVENT_REPLROLECHANGED_NOW_MASTER)) {
+        return REDISMODULE_ERR;
+    }
+
+    /* replication related hooks */
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_ReplicationRoleChanged, roleChangeCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_ReplicaChange, replicationChangeCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_MasterLinkChange, rasterLinkChangeCallback);
+
+    /* persistence related hooks */
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_Persistence, persistenceCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_Loading, loadingCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_LoadingProgress, loadingProgressCallback);
+
+    /* other hooks */
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_ClientChange, clientChangeCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_FlushDB, flushdbCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_Shutdown, shutdownCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_CronLoop, cronLoopCallback);
+
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_ModuleChange, moduleChangeCallback);
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_SwapDB, swapDbCallback);
+
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_Config, configChangeCallback);
+
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_Key, keyInfoCallback);
+
+    event_log = RedisModule_CreateDict(ctx);
+    removed_event_log = RedisModule_CreateDict(ctx);
+    removed_subevent_type = RedisModule_CreateDict(ctx);
+    removed_expiry_log = RedisModule_CreateDict(ctx);
+
+    if (RedisModule_CreateCommand(ctx,"hooks.event_count", cmdEventCount,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"hooks.event_last", cmdEventLast,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"hooks.clear", cmdEventsClear,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"hooks.is_key_removed", cmdIsKeyRemoved,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"hooks.pexpireat", cmdKeyExpiry,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (argc == 1) {
+        const char *ptr = RedisModule_StringPtrLen(argv[0], NULL);
+        if (!strcasecmp(ptr, "noload")) {
+            /* This is a hint that we return ERR at the last moment of OnLoad. */
+            RedisModule_FreeDict(ctx, event_log);
+            RedisModule_FreeDict(ctx, removed_event_log);
+            RedisModule_FreeDict(ctx, removed_subevent_type);
+            RedisModule_FreeDict(ctx, removed_expiry_log);
+            return REDISMODULE_ERR;
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    clearEvents(ctx);
+    RedisModule_FreeDict(ctx, event_log);
+    event_log = NULL;
+
+    RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(removed_event_log, "^", NULL, 0);
+    char* key;
+    size_t keyLen;
+    RedisModuleString* val;
+    while((key = RedisModule_DictNextC(iter, &keyLen, (void**)&val))){
+        RedisModule_FreeString(ctx, val);
+    }
+    RedisModule_FreeDict(ctx, removed_event_log);
+    RedisModule_DictIteratorStop(iter);
+    removed_event_log = NULL;
+
+    RedisModule_FreeDict(ctx, removed_subevent_type);
+    removed_subevent_type = NULL;
+
+    iter = RedisModule_DictIteratorStartC(removed_expiry_log, "^", NULL, 0);
+    while((key = RedisModule_DictNextC(iter, &keyLen, (void**)&val))){
+        RedisModule_FreeString(ctx, val);
+    }
+    RedisModule_FreeDict(ctx, removed_expiry_log);
+    RedisModule_DictIteratorStop(iter);
+    removed_expiry_log = NULL;
+
+    return REDISMODULE_OK;
+}
+
diff --git a/tests/modules/infotest.c b/tests/modules/infotest.c
new file mode 100644
index 0000000..87a89dc
--- /dev/null
+++ b/tests/modules/infotest.c
@@ -0,0 +1,119 @@
+#include "redismodule.h"
+
+#include <string.h>
+
+void InfoFunc(RedisModuleInfoCtx *ctx, int for_crash_report) {
+    RedisModule_InfoAddSection(ctx, "");
+    RedisModule_InfoAddFieldLongLong(ctx, "global", -2);
+    RedisModule_InfoAddFieldULongLong(ctx, "uglobal", (unsigned long long)-2);
+
+    RedisModule_InfoAddSection(ctx, "Spanish");
+    RedisModule_InfoAddFieldCString(ctx, "uno", "one");
+    RedisModule_InfoAddFieldLongLong(ctx, "dos", 2);
+
+    RedisModule_InfoAddSection(ctx, "Italian");
+    RedisModule_InfoAddFieldLongLong(ctx, "due", 2);
+    RedisModule_InfoAddFieldDouble(ctx, "tre", 3.3);
+
+    RedisModule_InfoAddSection(ctx, "keyspace");
+    RedisModule_InfoBeginDictField(ctx, "db0");
+    RedisModule_InfoAddFieldLongLong(ctx, "keys", 3);
+    RedisModule_InfoAddFieldLongLong(ctx, "expires", 1);
+    RedisModule_InfoEndDictField(ctx);
+
+    RedisModule_InfoAddSection(ctx, "unsafe");
+    RedisModule_InfoBeginDictField(ctx, "unsafe:field");
+    RedisModule_InfoAddFieldLongLong(ctx, "value", 1);
+    RedisModule_InfoEndDictField(ctx);
+
+    if (for_crash_report) {
+        RedisModule_InfoAddSection(ctx, "Klingon");
+        RedisModule_InfoAddFieldCString(ctx, "one", "wa’");
+        RedisModule_InfoAddFieldCString(ctx, "two", "cha’");
+        RedisModule_InfoAddFieldCString(ctx, "three", "wej");
+    }
+
+}
+
+int info_get(RedisModuleCtx *ctx, RedisModuleString **argv, int argc, char field_type)
+{
+    if (argc != 3 && argc != 4) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    int err = REDISMODULE_OK;
+    const char *section, *field;
+    section = RedisModule_StringPtrLen(argv[1], NULL);
+    field = RedisModule_StringPtrLen(argv[2], NULL);
+    RedisModuleServerInfoData *info = RedisModule_GetServerInfo(ctx, section);
+    if (field_type=='i') {
+        long long ll = RedisModule_ServerInfoGetFieldSigned(info, field, &err);
+        if (err==REDISMODULE_OK)
+            RedisModule_ReplyWithLongLong(ctx, ll);
+    } else if (field_type=='u') {
+        unsigned long long ll = (unsigned long long)RedisModule_ServerInfoGetFieldUnsigned(info, field, &err);
+        if (err==REDISMODULE_OK)
+            RedisModule_ReplyWithLongLong(ctx, ll);
+    } else if (field_type=='d') {
+        double d = RedisModule_ServerInfoGetFieldDouble(info, field, &err);
+        if (err==REDISMODULE_OK)
+            RedisModule_ReplyWithDouble(ctx, d);
+    } else if (field_type=='c') {
+        const char *str = RedisModule_ServerInfoGetFieldC(info, field);
+        if (str)
+            RedisModule_ReplyWithCString(ctx, str);
+    } else {
+        RedisModuleString *str = RedisModule_ServerInfoGetField(ctx, info, field);
+        if (str) {
+            RedisModule_ReplyWithString(ctx, str);
+            RedisModule_FreeString(ctx, str);
+        } else
+            err=REDISMODULE_ERR;
+    }
+    if (err!=REDISMODULE_OK)
+        RedisModule_ReplyWithError(ctx, "not found");
+    RedisModule_FreeServerInfo(ctx, info);
+    return REDISMODULE_OK;
+}
+
+int info_gets(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    return info_get(ctx, argv, argc, 's');
+}
+
+int info_getc(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    return info_get(ctx, argv, argc, 'c');
+}
+
+int info_geti(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    return info_get(ctx, argv, argc, 'i');
+}
+
+int info_getu(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    return info_get(ctx, argv, argc, 'u');
+}
+
+int info_getd(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    return info_get(ctx, argv, argc, 'd');
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"infotest",1,REDISMODULE_APIVER_1)
+            == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_RegisterInfoFunc(ctx, InfoFunc) == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"info.gets", info_gets,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"info.getc", info_getc,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"info.geti", info_geti,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"info.getu", info_getu,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"info.getd", info_getd,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/keyspace_events.c b/tests/modules/keyspace_events.c
new file mode 100644
index 0000000..1a284b5
--- /dev/null
+++ b/tests/modules/keyspace_events.c
@@ -0,0 +1,440 @@
+/* This module is used to test the server keyspace events API.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2020, Meir Shpilraien <meir at redislabs dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE /* For usleep */
+
+#include "redismodule.h"
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+
+ustime_t cached_time = 0;
+
+/** stores all the keys on which we got 'loaded' keyspace notification **/
+RedisModuleDict *loaded_event_log = NULL;
+/** stores all the keys on which we got 'module' keyspace notification **/
+RedisModuleDict *module_event_log = NULL;
+
+/** Counts how many deleted KSN we got on keys with a prefix of "count_dels_" **/
+static size_t dels = 0;
+
+static int KeySpace_NotificationLoaded(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+
+    if(strcmp(event, "loaded") == 0){
+        const char* keyName = RedisModule_StringPtrLen(key, NULL);
+        int nokey;
+        RedisModule_DictGetC(loaded_event_log, (void*)keyName, strlen(keyName), &nokey);
+        if(nokey){
+            RedisModule_DictSetC(loaded_event_log, (void*)keyName, strlen(keyName), RedisModule_HoldString(ctx, key));
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationGeneric(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(type);
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+    if (strncmp(key_str, "count_dels_", 11) == 0 && strcmp(event, "del") == 0) {
+        if (RedisModule_GetContextFlags(ctx) & REDISMODULE_CTX_FLAGS_MASTER) {
+            dels++;
+            RedisModule_Replicate(ctx, "keyspace.incr_dels", "");
+        }
+        return REDISMODULE_OK;
+    }
+    if (cached_time) {
+        RedisModule_Assert(cached_time == RedisModule_CachedMicroseconds());
+        usleep(1);
+        RedisModule_Assert(cached_time != RedisModule_Microseconds());
+    }
+
+    if (strcmp(event, "del") == 0) {
+        RedisModuleString *copykey = RedisModule_CreateStringPrintf(ctx, "%s_copy", RedisModule_StringPtrLen(key, NULL));
+        RedisModuleCallReply* rep = RedisModule_Call(ctx, "DEL", "s!", copykey);
+        RedisModule_FreeString(ctx, copykey);
+        RedisModule_FreeCallReply(rep);
+
+        int ctx_flags = RedisModule_GetContextFlags(ctx);
+        if (ctx_flags & REDISMODULE_CTX_FLAGS_LUA) {
+            RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "c", "lua");
+            RedisModule_FreeCallReply(rep);
+        }
+        if (ctx_flags & REDISMODULE_CTX_FLAGS_MULTI) {
+            RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "c", "multi");
+            RedisModule_FreeCallReply(rep);
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationExpired(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    REDISMODULE_NOT_USED(key);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "c!", "testkeyspace:expired");
+    RedisModule_FreeCallReply(rep);
+
+    return REDISMODULE_OK;
+}
+
+/* This key miss notification handler is performing a write command inside the notification callback.
+ * Notice, it is discourage and currently wrong to perform a write command inside key miss event.
+ * It can cause read commands to be replicated to the replica/aof. This test is here temporary (for coverage and
+ * verification that it's not crashing). */
+static int KeySpace_NotificationModuleKeyMiss(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    REDISMODULE_NOT_USED(key);
+
+    int flags = RedisModule_GetContextFlags(ctx);
+    if (!(flags & REDISMODULE_CTX_FLAGS_MASTER)) {
+        return REDISMODULE_OK; // ignore the event on replica
+    }
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "incr", "!c", "missed");
+    RedisModule_FreeCallReply(rep);
+
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationModuleString(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    RedisModuleKey *redis_key = RedisModule_OpenKey(ctx, key, REDISMODULE_READ);
+
+    size_t len = 0;
+    /* RedisModule_StringDMA could change the data format and cause the old robj to be freed.
+     * This code verifies that such format change will not cause any crashes.*/
+    char *data = RedisModule_StringDMA(redis_key, &len, REDISMODULE_READ);
+    int res = strncmp(data, "dummy", 5);
+    REDISMODULE_NOT_USED(res);
+
+    RedisModule_CloseKey(redis_key);
+
+    return REDISMODULE_OK;
+}
+
+static void KeySpace_PostNotificationStringFreePD(void *pd) {
+    RedisModule_FreeString(NULL, pd);
+}
+
+static void KeySpace_PostNotificationString(RedisModuleCtx *ctx, void *pd) {
+    REDISMODULE_NOT_USED(ctx);
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "incr", "!s", pd);
+    RedisModule_FreeCallReply(rep);
+}
+
+static int KeySpace_NotificationModuleStringPostNotificationJob(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+
+    if (strncmp(key_str, "string1_", 8) != 0) {
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleString *new_key = RedisModule_CreateStringPrintf(NULL, "string_changed{%s}", key_str);
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationModule(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+
+    const char* keyName = RedisModule_StringPtrLen(key, NULL);
+    int nokey;
+    RedisModule_DictGetC(module_event_log, (void*)keyName, strlen(keyName), &nokey);
+    if(nokey){
+        RedisModule_DictSetC(module_event_log, (void*)keyName, strlen(keyName), RedisModule_HoldString(ctx, key));
+    }
+    return REDISMODULE_OK;
+}
+
+static int cmdNotify(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc != 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    RedisModule_NotifyKeyspaceEvent(ctx, REDISMODULE_NOTIFY_MODULE, "notify", argv[1]);
+    RedisModule_ReplyWithNull(ctx);
+    return REDISMODULE_OK;
+}
+
+static int cmdIsModuleKeyNotified(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc != 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* key  = RedisModule_StringPtrLen(argv[1], NULL);
+
+    int nokey;
+    RedisModuleString* keyStr = RedisModule_DictGetC(module_event_log, (void*)key, strlen(key), &nokey);
+
+    RedisModule_ReplyWithArray(ctx, 2);
+    RedisModule_ReplyWithLongLong(ctx, !nokey);
+    if(nokey){
+        RedisModule_ReplyWithNull(ctx);
+    }else{
+        RedisModule_ReplyWithString(ctx, keyStr);
+    }
+    return REDISMODULE_OK;
+}
+
+static int cmdIsKeyLoaded(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc != 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* key  = RedisModule_StringPtrLen(argv[1], NULL);
+
+    int nokey;
+    RedisModuleString* keyStr = RedisModule_DictGetC(loaded_event_log, (void*)key, strlen(key), &nokey);
+
+    RedisModule_ReplyWithArray(ctx, 2);
+    RedisModule_ReplyWithLongLong(ctx, !nokey);
+    if(nokey){
+        RedisModule_ReplyWithNull(ctx);
+    }else{
+        RedisModule_ReplyWithString(ctx, keyStr);
+    }
+    return REDISMODULE_OK;
+}
+
+static int cmdDelKeyCopy(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    cached_time = RedisModule_CachedMicroseconds();
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "DEL", "s!", argv[1]);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    cached_time = 0;
+    return REDISMODULE_OK;
+}
+
+/* Call INCR and propagate using RM_Call with `!`. */
+static int cmdIncrCase1(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "s!", argv[1]);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    return REDISMODULE_OK;
+}
+
+/* Call INCR and propagate using RM_Replicate. */
+static int cmdIncrCase2(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "s", argv[1]);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    RedisModule_Replicate(ctx, "INCR", "s", argv[1]);
+    return REDISMODULE_OK;
+}
+
+/* Call INCR and propagate using RM_ReplicateVerbatim. */
+static int cmdIncrCase3(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2)
+        return RedisModule_WrongArity(ctx);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "s", argv[1]);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+static int cmdIncrDels(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    dels++;
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+static int cmdGetDels(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    return RedisModule_ReplyWithLongLong(ctx, dels);
+}
+
+/* This function must be present on each Redis module. It is used in order to
+ * register the commands into the Redis server. */
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (RedisModule_Init(ctx,"testkeyspace",1,REDISMODULE_APIVER_1) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    loaded_event_log = RedisModule_CreateDict(ctx);
+    module_event_log = RedisModule_CreateDict(ctx);
+
+    int keySpaceAll = RedisModule_GetKeyspaceNotificationFlagsAll();
+
+    if (!(keySpaceAll & REDISMODULE_NOTIFY_LOADED)) {
+        // REDISMODULE_NOTIFY_LOADED event are not supported we can not start
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_LOADED, KeySpace_NotificationLoaded) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_GENERIC, KeySpace_NotificationGeneric) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_EXPIRED, KeySpace_NotificationExpired) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_MODULE, KeySpace_NotificationModule) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_KEY_MISS, KeySpace_NotificationModuleKeyMiss) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NotificationModuleString) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NotificationModuleStringPostNotificationJob) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx,"keyspace.notify", cmdNotify,"",0,0,0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx,"keyspace.is_module_key_notified", cmdIsModuleKeyNotified,"",0,0,0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx,"keyspace.is_key_loaded", cmdIsKeyLoaded,"",0,0,0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "keyspace.del_key_copy", cmdDelKeyCopy,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+    
+    if (RedisModule_CreateCommand(ctx, "keyspace.incr_case1", cmdIncrCase1,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+    
+    if (RedisModule_CreateCommand(ctx, "keyspace.incr_case2", cmdIncrCase2,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+    
+    if (RedisModule_CreateCommand(ctx, "keyspace.incr_case3", cmdIncrCase3,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "keyspace.incr_dels", cmdIncrDels,
+                                  "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx, "keyspace.get_dels", cmdGetDels,
+                                  "readonly", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (argc == 1) {
+        const char *ptr = RedisModule_StringPtrLen(argv[0], NULL);
+        if (!strcasecmp(ptr, "noload")) {
+            /* This is a hint that we return ERR at the last moment of OnLoad. */
+            RedisModule_FreeDict(ctx, loaded_event_log);
+            RedisModule_FreeDict(ctx, module_event_log);
+            return REDISMODULE_ERR;
+        }
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(loaded_event_log, "^", NULL, 0);
+    char* key;
+    size_t keyLen;
+    RedisModuleString* val;
+    while((key = RedisModule_DictNextC(iter, &keyLen, (void**)&val))){
+        RedisModule_FreeString(ctx, val);
+    }
+    RedisModule_FreeDict(ctx, loaded_event_log);
+    RedisModule_DictIteratorStop(iter);
+    loaded_event_log = NULL;
+
+    iter = RedisModule_DictIteratorStartC(module_event_log, "^", NULL, 0);
+    while((key = RedisModule_DictNextC(iter, &keyLen, (void**)&val))){
+        RedisModule_FreeString(ctx, val);
+    }
+    RedisModule_FreeDict(ctx, module_event_log);
+    RedisModule_DictIteratorStop(iter);
+    module_event_log = NULL;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/keyspecs.c b/tests/modules/keyspecs.c
new file mode 100644
index 0000000..0a70de8
--- /dev/null
+++ b/tests/modules/keyspecs.c
@@ -0,0 +1,236 @@
+#include "redismodule.h"
+
+#define UNUSED(V) ((void) V)
+
+/* This function implements all commands in this module. All we care about is
+ * the COMMAND metadata anyway. */
+int kspec_impl(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    /* Handle getkeys-api introspection (for "kspec.nonewithgetkeys")  */
+    if (RedisModule_IsKeysPositionRequest(ctx)) {
+        for (int i = 1; i < argc; i += 2)
+            RedisModule_KeyAtPosWithFlags(ctx, i, REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS);
+
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int createKspecNone(RedisModuleCtx *ctx) {
+    /* A command without keyspecs; only the legacy (first,last,step) triple (MSET like spec). */
+    if (RedisModule_CreateCommand(ctx,"kspec.none",kspec_impl,"",1,-1,2) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
+
+int createKspecNoneWithGetkeys(RedisModuleCtx *ctx) {
+    /* A command without keyspecs; only the legacy (first,last,step) triple (MSET like spec), but also has a getkeys callback */
+    if (RedisModule_CreateCommand(ctx,"kspec.nonewithgetkeys",kspec_impl,"getkeys-api",1,-1,2) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
+
+int createKspecTwoRanges(RedisModuleCtx *ctx) {
+    /* Test that two position/range-based key specs are combined to produce the
+     * legacy (first,last,step) values representing both keys. */
+    if (RedisModule_CreateCommand(ctx,"kspec.tworanges",kspec_impl,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *command = RedisModule_GetCommand(ctx,"kspec.tworanges");
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .arity = -2,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 2,
+                /* Omitted find_keys_type is shorthand for RANGE {0,1,0} */
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(command, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int createKspecTwoRangesWithGap(RedisModuleCtx *ctx) {
+    /* Test that two position/range-based key specs are combined to produce the
+     * legacy (first,last,step) values representing just one key. */
+    if (RedisModule_CreateCommand(ctx,"kspec.tworangeswithgap",kspec_impl,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *command = RedisModule_GetCommand(ctx,"kspec.tworangeswithgap");
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .arity = -2,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 3,
+                /* Omitted find_keys_type is shorthand for RANGE {0,1,0} */
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(command, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int createKspecKeyword(RedisModuleCtx *ctx) {
+    /* Only keyword-based specs. The legacy triple is wiped and set to (0,0,0). */
+    if (RedisModule_CreateCommand(ctx,"kspec.keyword",kspec_impl,"",3,-1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *command = RedisModule_GetCommand(ctx,"kspec.keyword");
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_KEYWORD,
+                .bs.keyword.keyword = "KEYS",
+                .bs.keyword.startfrom = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {-1,1,0}
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(command, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int createKspecComplex1(RedisModuleCtx *ctx) {
+    /* First is a range a single key. The rest are keyword-based specs. */
+    if (RedisModule_CreateCommand(ctx,"kspec.complex1",kspec_impl,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *command = RedisModule_GetCommand(ctx,"kspec.complex1");
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RO,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_KEYWORD,
+                .bs.keyword.keyword = "STORE",
+                .bs.keyword.startfrom = 2,
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_KEYWORD,
+                .bs.keyword.keyword = "KEYS",
+                .bs.keyword.startfrom = 2,
+                .find_keys_type = REDISMODULE_KSPEC_FK_KEYNUM,
+                .fk.keynum = {0,1,1}
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(command, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int createKspecComplex2(RedisModuleCtx *ctx) {
+    /* First is not legacy, more than STATIC_KEYS_SPECS_NUM specs */
+    if (RedisModule_CreateCommand(ctx,"kspec.complex2",kspec_impl,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *command = RedisModule_GetCommand(ctx,"kspec.complex2");
+    RedisModuleCommandInfo info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_KEYWORD,
+                .bs.keyword.keyword = "STORE",
+                .bs.keyword.startfrom = 5,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 2,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 3,
+                .find_keys_type = REDISMODULE_KSPEC_FK_KEYNUM,
+                .fk.keynum = {0,1,1}
+            },
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_KEYWORD,
+                .bs.keyword.keyword = "MOREKEYS",
+                .bs.keyword.startfrom = 5,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {-1,1,0}
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(command, &info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "keyspecs", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (createKspecNone(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecNoneWithGetkeys(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecTwoRanges(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecTwoRangesWithGap(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecKeyword(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecComplex1(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    if (createKspecComplex2(ctx) == REDISMODULE_ERR) return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/list.c b/tests/modules/list.c
new file mode 100644
index 0000000..401b2d8
--- /dev/null
+++ b/tests/modules/list.c
@@ -0,0 +1,252 @@
+#include "redismodule.h"
+#include <assert.h>
+#include <errno.h>
+#include <strings.h>
+
+/* LIST.GETALL key [REVERSE] */
+int list_getall(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 2 || argc > 3) return RedisModule_WrongArity(ctx);
+    int reverse = (argc == 3 &&
+                   !strcasecmp(RedisModule_StringPtrLen(argv[2], NULL),
+                               "REVERSE"));
+    RedisModule_AutoMemory(ctx);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    if (RedisModule_KeyType(key) != REDISMODULE_KEYTYPE_LIST) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+    long n = RedisModule_ValueLength(key);
+    RedisModule_ReplyWithArray(ctx, n);
+    if (!reverse) {
+        for (long i = 0; i < n; i++) {
+            RedisModuleString *elem = RedisModule_ListGet(key, i);
+            RedisModule_ReplyWithString(ctx, elem);
+            RedisModule_FreeString(ctx, elem);
+        }
+    } else {
+        for (long i = -1; i >= -n; i--) {
+            RedisModuleString *elem = RedisModule_ListGet(key, i);
+            RedisModule_ReplyWithString(ctx, elem);
+            RedisModule_FreeString(ctx, elem);
+        }
+    }
+
+    /* Test error condition: index out of bounds */
+    assert(RedisModule_ListGet(key, n) == NULL);
+    assert(errno == EDOM); /* no more elements in list */
+
+    /* RedisModule_CloseKey(key); //implicit, done by auto memory */
+    return REDISMODULE_OK;
+}
+
+/* LIST.EDIT key [REVERSE] cmdstr [value ..]
+ *
+ * cmdstr is a string of the following characters:
+ *
+ *     k -- keep
+ *     d -- delete
+ *     i -- insert value from args
+ *     r -- replace with value from args
+ *
+ * The number of occurrences of "i" and "r" in cmdstr) should correspond to the
+ * number of args after cmdstr.
+ *
+ * Reply with a RESP3 Map, containing the number of edits (inserts, replaces, deletes)
+ * performed, as well as the last index and the entry it points to.
+ */
+int list_edit(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3) return RedisModule_WrongArity(ctx);
+    RedisModule_AutoMemory(ctx);
+    int argpos = 1; /* the next arg */
+
+    /* key */
+    int keymode = REDISMODULE_READ | REDISMODULE_WRITE;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[argpos++], keymode);
+    if (RedisModule_KeyType(key) != REDISMODULE_KEYTYPE_LIST) {
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    /* REVERSE */
+    int reverse = 0;
+    if (argc >= 4 &&
+        !strcasecmp(RedisModule_StringPtrLen(argv[argpos], NULL), "REVERSE")) {
+        reverse = 1;
+        argpos++;
+    }
+
+    /* cmdstr */
+    size_t cmdstr_len;
+    const char *cmdstr = RedisModule_StringPtrLen(argv[argpos++], &cmdstr_len);
+
+    /* validate cmdstr vs. argc */
+    long num_req_args = 0;
+    long min_list_length = 0;
+    for (size_t cmdpos = 0; cmdpos < cmdstr_len; cmdpos++) {
+        char c = cmdstr[cmdpos];
+        if (c == 'i' || c == 'r') num_req_args++;
+        if (c == 'd' || c == 'r' || c == 'k') min_list_length++;
+    }
+    if (argc < argpos + num_req_args) {
+        return RedisModule_ReplyWithError(ctx, "ERR too few args");
+    }
+    if ((long)RedisModule_ValueLength(key) < min_list_length) {
+        return RedisModule_ReplyWithError(ctx, "ERR list too short");
+    }
+
+    /* Iterate over the chars in cmdstr (edit instructions) */
+    long long num_inserts = 0, num_deletes = 0, num_replaces = 0;
+    long index = reverse ? -1 : 0;
+    RedisModuleString *value;
+
+    for (size_t cmdpos = 0; cmdpos < cmdstr_len; cmdpos++) {
+        switch (cmdstr[cmdpos]) {
+        case 'i': /* insert */
+            value = argv[argpos++];
+            assert(RedisModule_ListInsert(key, index, value) == REDISMODULE_OK);
+            index += reverse ? -1 : 1;
+            num_inserts++;
+            break;
+        case 'd': /* delete */
+            assert(RedisModule_ListDelete(key, index) == REDISMODULE_OK);
+            num_deletes++;
+            break;
+        case 'r': /* replace */
+            value = argv[argpos++];
+            assert(RedisModule_ListSet(key, index, value) == REDISMODULE_OK);
+            index += reverse ? -1 : 1;
+            num_replaces++;
+            break;
+        case 'k': /* keep */
+            index += reverse ? -1 : 1;
+            break;
+        }
+    }
+
+    RedisModuleString *v = RedisModule_ListGet(key, index);
+    RedisModule_ReplyWithMap(ctx, v ? 5 : 4);
+    RedisModule_ReplyWithCString(ctx, "i");
+    RedisModule_ReplyWithLongLong(ctx, num_inserts);
+    RedisModule_ReplyWithCString(ctx, "d");
+    RedisModule_ReplyWithLongLong(ctx, num_deletes);
+    RedisModule_ReplyWithCString(ctx, "r");
+    RedisModule_ReplyWithLongLong(ctx, num_replaces);
+    RedisModule_ReplyWithCString(ctx, "index");
+    RedisModule_ReplyWithLongLong(ctx, index);
+    if (v) {
+        RedisModule_ReplyWithCString(ctx, "entry");
+        RedisModule_ReplyWithString(ctx, v);
+        RedisModule_FreeString(ctx, v);
+    } 
+
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* Reply based on errno as set by the List API functions. */
+static int replyByErrno(RedisModuleCtx *ctx) {
+    switch (errno) {
+    case EDOM:
+        return RedisModule_ReplyWithError(ctx, "ERR index out of bounds");
+    case ENOTSUP:
+        return RedisModule_ReplyWithError(ctx, REDISMODULE_ERRORMSG_WRONGTYPE);
+    default: assert(0); /* Can't happen */
+    }
+}
+
+/* LIST.GET key index */
+int list_get(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    long long index;
+    if (RedisModule_StringToLongLong(argv[2], &index) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx, "ERR index must be a number");
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    RedisModuleString *value = RedisModule_ListGet(key, index);
+    if (value) {
+        RedisModule_ReplyWithString(ctx, value);
+        RedisModule_FreeString(ctx, value);
+    } else {
+        replyByErrno(ctx);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* LIST.SET key index value */
+int list_set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) return RedisModule_WrongArity(ctx);
+    long long index;
+    if (RedisModule_StringToLongLong(argv[2], &index) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "ERR index must be a number");
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_ListSet(key, index, argv[3]) == REDISMODULE_OK) {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        replyByErrno(ctx);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* LIST.INSERT key index value
+ *
+ * If index is negative, value is inserted after, otherwise before the element
+ * at index.
+ */
+int list_insert(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) return RedisModule_WrongArity(ctx);
+    long long index;
+    if (RedisModule_StringToLongLong(argv[2], &index) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "ERR index must be a number");
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_ListInsert(key, index, argv[3]) == REDISMODULE_OK) {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        replyByErrno(ctx);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* LIST.DELETE key index */
+int list_delete(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    long long index;
+    if (RedisModule_StringToLongLong(argv[2], &index) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "ERR index must be a number");
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_ListDelete(key, index) == REDISMODULE_OK) {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        replyByErrno(ctx);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "list", 1, REDISMODULE_APIVER_1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.getall", list_getall, "",
+                                  1, 1, 1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.edit", list_edit, "write",
+                                  1, 1, 1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.get", list_get, "write",
+                                  1, 1, 1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.set", list_set, "write",
+                                  1, 1, 1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.insert", list_insert, "write",
+                                  1, 1, 1) == REDISMODULE_OK &&
+        RedisModule_CreateCommand(ctx, "list.delete", list_delete, "write",
+                                  1, 1, 1) == REDISMODULE_OK) {
+        return REDISMODULE_OK;
+    } else {
+        return REDISMODULE_ERR;
+    }
+}
diff --git a/tests/modules/mallocsize.c b/tests/modules/mallocsize.c
new file mode 100644
index 0000000..a1d31c1
--- /dev/null
+++ b/tests/modules/mallocsize.c
@@ -0,0 +1,237 @@
+#include "redismodule.h"
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+
+#define UNUSED(V) ((void) V)
+
+/* Registered type */
+RedisModuleType *mallocsize_type = NULL;
+
+typedef enum {
+    UDT_RAW,
+    UDT_STRING,
+    UDT_DICT
+} udt_type_t;
+
+typedef struct {
+    void *ptr;
+    size_t len;
+} raw_t;
+
+typedef struct {
+    udt_type_t type;
+    union {
+        raw_t raw;
+        RedisModuleString *str;
+        RedisModuleDict *dict;
+    } data;
+} udt_t;
+
+void udt_free(void *value) {
+    udt_t *udt = value;
+    switch (udt->type) {
+        case (UDT_RAW): {
+            RedisModule_Free(udt->data.raw.ptr);
+            break;
+        }
+        case (UDT_STRING): {
+            RedisModule_FreeString(NULL, udt->data.str);
+            break;
+        }
+        case (UDT_DICT): {
+            RedisModuleString *dk, *dv;
+            RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(udt->data.dict, "^", NULL, 0);
+            while((dk = RedisModule_DictNext(NULL, iter, (void **)&dv)) != NULL) {
+                RedisModule_FreeString(NULL, dk);
+                RedisModule_FreeString(NULL, dv);
+            }
+            RedisModule_DictIteratorStop(iter);
+            RedisModule_FreeDict(NULL, udt->data.dict);
+            break;
+        }
+    }
+    RedisModule_Free(udt);
+}
+
+void udt_rdb_save(RedisModuleIO *rdb, void *value) {
+    udt_t *udt = value;
+    RedisModule_SaveUnsigned(rdb, udt->type);
+    switch (udt->type) {
+        case (UDT_RAW): {
+            RedisModule_SaveStringBuffer(rdb, udt->data.raw.ptr, udt->data.raw.len);
+            break;
+        }
+        case (UDT_STRING): {
+            RedisModule_SaveString(rdb, udt->data.str);
+            break;
+        }
+        case (UDT_DICT): {
+            RedisModule_SaveUnsigned(rdb, RedisModule_DictSize(udt->data.dict));
+            RedisModuleString *dk, *dv;
+            RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(udt->data.dict, "^", NULL, 0);
+            while((dk = RedisModule_DictNext(NULL, iter, (void **)&dv)) != NULL) {
+                RedisModule_SaveString(rdb, dk);
+                RedisModule_SaveString(rdb, dv);
+                RedisModule_FreeString(NULL, dk); /* Allocated by RedisModule_DictNext */
+            }
+            RedisModule_DictIteratorStop(iter);
+            break;
+        }
+    }
+}
+
+void *udt_rdb_load(RedisModuleIO *rdb, int encver) {
+    if (encver != 0)
+        return NULL;
+    udt_t *udt = RedisModule_Alloc(sizeof(*udt));
+    udt->type = RedisModule_LoadUnsigned(rdb);
+    switch (udt->type) {
+        case (UDT_RAW): {
+            udt->data.raw.ptr = RedisModule_LoadStringBuffer(rdb, &udt->data.raw.len);
+            break;
+        }
+        case (UDT_STRING): {
+            udt->data.str = RedisModule_LoadString(rdb);
+            break;
+        }
+        case (UDT_DICT): {
+            long long dict_len = RedisModule_LoadUnsigned(rdb);
+            udt->data.dict = RedisModule_CreateDict(NULL);
+            for (int i = 0; i < dict_len; i += 2) {
+                RedisModuleString *key = RedisModule_LoadString(rdb);
+                RedisModuleString *val = RedisModule_LoadString(rdb);
+                RedisModule_DictSet(udt->data.dict, key, val);
+            }
+            break;
+        }
+    }
+
+    return udt;
+}
+
+size_t udt_mem_usage(RedisModuleKeyOptCtx *ctx, const void *value, size_t sample_size) {
+    UNUSED(ctx);
+    UNUSED(sample_size);
+    
+    const udt_t *udt = value;
+    size_t size = sizeof(*udt);
+    
+    switch (udt->type) {
+        case (UDT_RAW): {
+            size += RedisModule_MallocSize(udt->data.raw.ptr);
+            break;
+        }
+        case (UDT_STRING): {
+            size += RedisModule_MallocSizeString(udt->data.str);
+            break;
+        }
+        case (UDT_DICT): {
+            void *dk;
+            size_t keylen;
+            RedisModuleString *dv;
+            RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(udt->data.dict, "^", NULL, 0);
+            while((dk = RedisModule_DictNextC(iter, &keylen, (void **)&dv)) != NULL) {
+                size += keylen;
+                size += RedisModule_MallocSizeString(dv);
+            }
+            RedisModule_DictIteratorStop(iter);
+            break;
+        }
+    }
+    
+    return size;
+}
+
+/* MALLOCSIZE.SETRAW key len */
+int cmd_setraw(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3)
+        return RedisModule_WrongArity(ctx);
+        
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+
+    udt_t *udt = RedisModule_Alloc(sizeof(*udt));
+    udt->type = UDT_RAW;
+    
+    long long raw_len;
+    RedisModule_StringToLongLong(argv[2], &raw_len);
+    udt->data.raw.ptr = RedisModule_Alloc(raw_len);
+    udt->data.raw.len = raw_len;
+    
+    RedisModule_ModuleTypeSetValue(key, mallocsize_type, udt);
+    RedisModule_CloseKey(key);
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+/* MALLOCSIZE.SETSTR key string */
+int cmd_setstr(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3)
+        return RedisModule_WrongArity(ctx);
+        
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+
+    udt_t *udt = RedisModule_Alloc(sizeof(*udt));
+    udt->type = UDT_STRING;
+    
+    udt->data.str = argv[2];
+    RedisModule_RetainString(ctx, argv[2]);
+    
+    RedisModule_ModuleTypeSetValue(key, mallocsize_type, udt);
+    RedisModule_CloseKey(key);
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+/* MALLOCSIZE.SETDICT key field value [field value ...] */
+int cmd_setdict(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 4 || argc % 2)
+        return RedisModule_WrongArity(ctx);
+        
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+
+    udt_t *udt = RedisModule_Alloc(sizeof(*udt));
+    udt->type = UDT_DICT;
+    
+    udt->data.dict = RedisModule_CreateDict(ctx);
+    for (int i = 2; i < argc; i += 2) {
+        RedisModule_DictSet(udt->data.dict, argv[i], argv[i+1]);
+        /* No need to retain argv[i], it is copied as the rax key */
+        RedisModule_RetainString(ctx, argv[i+1]);   
+    }
+    
+    RedisModule_ModuleTypeSetValue(key, mallocsize_type, udt);
+    RedisModule_CloseKey(key);
+
+    return RedisModule_ReplyWithSimpleString(ctx, "OK");
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    if (RedisModule_Init(ctx,"mallocsize",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+        
+    RedisModuleTypeMethods tm = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = udt_rdb_load,
+        .rdb_save = udt_rdb_save,
+        .free = udt_free,
+        .mem_usage2 = udt_mem_usage,
+    };
+
+    mallocsize_type = RedisModule_CreateDataType(ctx, "allocsize", 0, &tm);
+    if (mallocsize_type == NULL)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "mallocsize.setraw", cmd_setraw, "", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+        
+    if (RedisModule_CreateCommand(ctx, "mallocsize.setstr", cmd_setstr, "", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+        
+    if (RedisModule_CreateCommand(ctx, "mallocsize.setdict", cmd_setdict, "", 1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/misc.c b/tests/modules/misc.c
new file mode 100644
index 0000000..46bfcb1
--- /dev/null
+++ b/tests/modules/misc.c
@@ -0,0 +1,571 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+#include <errno.h>
+#include <limits.h>
+
+#define UNUSED(x) (void)(x)
+
+static int n_events = 0;
+
+static int KeySpace_NotificationModuleKeyMissExpired(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    UNUSED(ctx);
+    UNUSED(type);
+    UNUSED(event);
+    UNUSED(key);
+    n_events++;
+    return REDISMODULE_OK;
+}
+
+int test_clear_n_events(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    n_events = 0;
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int test_get_n_events(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModule_ReplyWithLongLong(ctx, n_events);
+    return REDISMODULE_OK;
+}
+
+int test_open_key_no_effects(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc<2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    int supportedMode = RedisModule_GetOpenKeyModesAll();
+    if (!(supportedMode & REDISMODULE_READ) || !(supportedMode & REDISMODULE_OPEN_KEY_NOEFFECTS)) {
+        RedisModule_ReplyWithError(ctx, "OpenKey modes are not supported");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ | REDISMODULE_OPEN_KEY_NOEFFECTS);
+    if (!key) {
+        RedisModule_ReplyWithError(ctx, "key not found");
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_CloseKey(key);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int test_call_generic(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc<2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    const char* cmdname = RedisModule_StringPtrLen(argv[1], NULL);
+    RedisModuleCallReply *reply = RedisModule_Call(ctx, cmdname, "v", argv+2, argc-2);
+    if (reply) {
+        RedisModule_ReplyWithCallReply(ctx, reply);
+        RedisModule_FreeCallReply(reply);
+    } else {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+    }
+    return REDISMODULE_OK;
+}
+
+int test_call_info(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    RedisModuleCallReply *reply;
+    if (argc>1)
+        reply = RedisModule_Call(ctx, "info", "s", argv[1]);
+    else
+        reply = RedisModule_Call(ctx, "info", "");
+    if (reply) {
+        RedisModule_ReplyWithCallReply(ctx, reply);
+        RedisModule_FreeCallReply(reply);
+    } else {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+    }
+    return REDISMODULE_OK;
+}
+
+int test_ld_conv(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    long double ld = 0.00000000000000001L;
+    const char *ldstr = "0.00000000000000001";
+    RedisModuleString *s1 = RedisModule_CreateStringFromLongDouble(ctx, ld, 1);
+    RedisModuleString *s2 =
+        RedisModule_CreateString(ctx, ldstr, strlen(ldstr));
+    if (RedisModule_StringCompare(s1, s2) != 0) {
+        char err[4096];
+        snprintf(err, 4096,
+            "Failed to convert long double to string ('%s' != '%s')",
+            RedisModule_StringPtrLen(s1, NULL),
+            RedisModule_StringPtrLen(s2, NULL));
+        RedisModule_ReplyWithError(ctx, err);
+        goto final;
+    }
+    long double ld2 = 0;
+    if (RedisModule_StringToLongDouble(s2, &ld2) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx,
+            "Failed to convert string to long double");
+        goto final;
+    }
+    if (ld2 != ld) {
+        char err[4096];
+        snprintf(err, 4096,
+            "Failed to convert string to long double (%.40Lf != %.40Lf)",
+            ld2,
+            ld);
+        RedisModule_ReplyWithError(ctx, err);
+        goto final;
+    }
+
+    /* Make sure we can't convert a string that has \0 in it */
+    char buf[4] = "123";
+    buf[1] = '\0';
+    RedisModuleString *s3 = RedisModule_CreateString(ctx, buf, 3);
+    long double ld3;
+    if (RedisModule_StringToLongDouble(s3, &ld3) == REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid string successfully converted to long double");
+        RedisModule_FreeString(ctx, s3);
+        goto final;
+    }
+    RedisModule_FreeString(ctx, s3);
+
+    RedisModule_ReplyWithLongDouble(ctx, ld2);
+final:
+    RedisModule_FreeString(ctx, s1);
+    RedisModule_FreeString(ctx, s2);
+    return REDISMODULE_OK;
+}
+
+int test_flushall(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_ResetDataset(1, 0);
+    RedisModule_ReplyWithCString(ctx, "Ok");
+    return REDISMODULE_OK;
+}
+
+int test_dbsize(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    long long ll = RedisModule_DbSize(ctx);
+    RedisModule_ReplyWithLongLong(ctx, ll);
+    return REDISMODULE_OK;
+}
+
+int test_randomkey(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleString *str = RedisModule_RandomKey(ctx);
+    RedisModule_ReplyWithString(ctx, str);
+    RedisModule_FreeString(ctx, str);
+    return REDISMODULE_OK;
+}
+
+int test_keyexists(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 2) return RedisModule_WrongArity(ctx);
+    RedisModuleString *key = argv[1];
+    int exists = RedisModule_KeyExists(ctx, key);
+    return RedisModule_ReplyWithBool(ctx, exists);
+}
+
+RedisModuleKey *open_key_or_reply(RedisModuleCtx *ctx, RedisModuleString *keyname, int mode) {
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, keyname, mode);
+    if (!key) {
+        RedisModule_ReplyWithError(ctx, "key not found");
+        return NULL;
+    }
+    return key;
+}
+
+int test_getlru(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc<2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = open_key_or_reply(ctx, argv[1], REDISMODULE_READ|REDISMODULE_OPEN_KEY_NOTOUCH);
+    mstime_t lru;
+    RedisModule_GetLRU(key, &lru);
+    RedisModule_ReplyWithLongLong(ctx, lru);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int test_setlru(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc<3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = open_key_or_reply(ctx, argv[1], REDISMODULE_READ|REDISMODULE_OPEN_KEY_NOTOUCH);
+    mstime_t lru;
+    if (RedisModule_StringToLongLong(argv[2], &lru) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "invalid idle time");
+        return REDISMODULE_OK;
+    }
+    int was_set = RedisModule_SetLRU(key, lru)==REDISMODULE_OK;
+    RedisModule_ReplyWithLongLong(ctx, was_set);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int test_getlfu(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc<2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = open_key_or_reply(ctx, argv[1], REDISMODULE_READ|REDISMODULE_OPEN_KEY_NOTOUCH);
+    mstime_t lfu;
+    RedisModule_GetLFU(key, &lfu);
+    RedisModule_ReplyWithLongLong(ctx, lfu);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int test_setlfu(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc<3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    RedisModuleKey *key = open_key_or_reply(ctx, argv[1], REDISMODULE_READ|REDISMODULE_OPEN_KEY_NOTOUCH);
+    mstime_t lfu;
+    if (RedisModule_StringToLongLong(argv[2], &lfu) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "invalid freq");
+        return REDISMODULE_OK;
+    }
+    int was_set = RedisModule_SetLFU(key, lfu)==REDISMODULE_OK;
+    RedisModule_ReplyWithLongLong(ctx, was_set);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int test_redisversion(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    (void) argv;
+    (void) argc;
+
+    int version = RedisModule_GetServerVersion();
+    int patch = version & 0x000000ff;
+    int minor = (version & 0x0000ff00) >> 8;
+    int major = (version & 0x00ff0000) >> 16;
+
+    RedisModuleString* vStr = RedisModule_CreateStringPrintf(ctx, "%d.%d.%d", major, minor, patch);
+    RedisModule_ReplyWithString(ctx, vStr);
+    RedisModule_FreeString(ctx, vStr);
+  
+    return REDISMODULE_OK;
+}
+
+int test_getclientcert(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    (void) argv;
+    (void) argc;
+
+    RedisModuleString *cert = RedisModule_GetClientCertificate(ctx,
+            RedisModule_GetClientId(ctx));
+    if (!cert) {
+        RedisModule_ReplyWithNull(ctx);
+    } else {
+        RedisModule_ReplyWithString(ctx, cert);
+        RedisModule_FreeString(ctx, cert);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int test_clientinfo(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    (void) argv;
+    (void) argc;
+
+    RedisModuleClientInfoV1 ci = REDISMODULE_CLIENTINFO_INITIALIZER_V1;
+    uint64_t client_id = RedisModule_GetClientId(ctx);
+
+    /* Check expected result from the V1 initializer. */
+    assert(ci.version == 1);
+    /* Trying to populate a future version of the struct should fail. */
+    ci.version = REDISMODULE_CLIENTINFO_VERSION + 1;
+    assert(RedisModule_GetClientInfoById(&ci, client_id) == REDISMODULE_ERR);
+
+    ci.version = 1;
+    if (RedisModule_GetClientInfoById(&ci, client_id) == REDISMODULE_ERR) {
+            RedisModule_ReplyWithError(ctx, "failed to get client info");
+            return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithArray(ctx, 10);
+    char flags[512];
+    snprintf(flags, sizeof(flags) - 1, "%s:%s:%s:%s:%s:%s",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_SSL ? "ssl" : "",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_PUBSUB ? "pubsub" : "",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_BLOCKED ? "blocked" : "",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_TRACKING ? "tracking" : "",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_UNIXSOCKET ? "unixsocket" : "",
+        ci.flags & REDISMODULE_CLIENTINFO_FLAG_MULTI ? "multi" : "");
+
+    RedisModule_ReplyWithCString(ctx, "flags");
+    RedisModule_ReplyWithCString(ctx, flags);
+    RedisModule_ReplyWithCString(ctx, "id");
+    RedisModule_ReplyWithLongLong(ctx, ci.id);
+    RedisModule_ReplyWithCString(ctx, "addr");
+    RedisModule_ReplyWithCString(ctx, ci.addr);
+    RedisModule_ReplyWithCString(ctx, "port");
+    RedisModule_ReplyWithLongLong(ctx, ci.port);
+    RedisModule_ReplyWithCString(ctx, "db");
+    RedisModule_ReplyWithLongLong(ctx, ci.db);
+
+    return REDISMODULE_OK;
+}
+
+int test_getname(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    (void)argv;
+    if (argc != 1) return RedisModule_WrongArity(ctx);
+    unsigned long long id = RedisModule_GetClientId(ctx);
+    RedisModuleString *name = RedisModule_GetClientNameById(ctx, id);
+    if (name == NULL)
+        return RedisModule_ReplyWithError(ctx, "-ERR No name");
+    RedisModule_ReplyWithString(ctx, name);
+    RedisModule_FreeString(ctx, name);
+    return REDISMODULE_OK;
+}
+
+int test_setname(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+    unsigned long long id = RedisModule_GetClientId(ctx);
+    if (RedisModule_SetClientNameById(id, argv[1]) == REDISMODULE_OK)
+        return RedisModule_ReplyWithSimpleString(ctx, "OK");
+    else
+        return RedisModule_ReplyWithError(ctx, strerror(errno));
+}
+
+int test_log_tsctx(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    RedisModuleCtx *tsctx = RedisModule_GetDetachedThreadSafeContext(ctx);
+
+    if (argc != 3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    char level[50];
+    size_t level_len;
+    const char *level_str = RedisModule_StringPtrLen(argv[1], &level_len);
+    snprintf(level, sizeof(level) - 1, "%.*s", (int) level_len, level_str);
+
+    size_t msg_len;
+    const char *msg_str = RedisModule_StringPtrLen(argv[2], &msg_len);
+
+    RedisModule_Log(tsctx, level, "%.*s", (int) msg_len, msg_str);
+    RedisModule_FreeThreadSafeContext(tsctx);
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int test_weird_cmd(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int test_monotonic_time(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModule_ReplyWithLongLong(ctx, RedisModule_MonotonicMicroseconds());
+    return REDISMODULE_OK;
+}
+
+/* wrapper for RM_Call */
+int test_rm_call(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc < 2){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char* cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, "Ev", argv + 2, argc - 2);
+    if(!rep){
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    }else{
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    return REDISMODULE_OK;
+}
+
+/* wrapper for RM_Call which also replicates the module command */
+int test_rm_call_replicate(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    test_rm_call(ctx, argv, argc);
+    RedisModule_ReplicateVerbatim(ctx);
+
+    return REDISMODULE_OK;
+}
+
+/* wrapper for RM_Call with flags */
+int test_rm_call_flags(RedisModuleCtx *ctx, RedisModuleString **argv, int argc){
+    if(argc < 3){
+        return RedisModule_WrongArity(ctx);
+    }
+
+    /* Append Ev to the provided flags. */
+    RedisModuleString *flags = RedisModule_CreateStringFromString(ctx, argv[1]);
+    RedisModule_StringAppendBuffer(ctx, flags, "Ev", 2);
+
+    const char* flg = RedisModule_StringPtrLen(flags, NULL);
+    const char* cmd = RedisModule_StringPtrLen(argv[2], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, flg, argv + 3, argc - 3);
+    if(!rep){
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    }else{
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    RedisModule_FreeString(ctx, flags);
+
+    return REDISMODULE_OK;
+}
+
+int test_ull_conv(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    unsigned long long ull = 18446744073709551615ULL;
+    const char *ullstr = "18446744073709551615";
+
+    RedisModuleString *s1 = RedisModule_CreateStringFromULongLong(ctx, ull);
+    RedisModuleString *s2 =
+        RedisModule_CreateString(ctx, ullstr, strlen(ullstr));
+    if (RedisModule_StringCompare(s1, s2) != 0) {
+        char err[4096];
+        snprintf(err, 4096,
+            "Failed to convert unsigned long long to string ('%s' != '%s')",
+            RedisModule_StringPtrLen(s1, NULL),
+            RedisModule_StringPtrLen(s2, NULL));
+        RedisModule_ReplyWithError(ctx, err);
+        goto final;
+    }
+    unsigned long long ull2 = 0;
+    if (RedisModule_StringToULongLong(s2, &ull2) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx,
+            "Failed to convert string to unsigned long long");
+        goto final;
+    }
+    if (ull2 != ull) {
+        char err[4096];
+        snprintf(err, 4096,
+            "Failed to convert string to unsigned long long (%llu != %llu)",
+            ull2,
+            ull);
+        RedisModule_ReplyWithError(ctx, err);
+        goto final;
+    }
+    
+    /* Make sure we can't convert a string more than ULLONG_MAX or less than 0 */
+    ullstr = "18446744073709551616";
+    RedisModuleString *s3 = RedisModule_CreateString(ctx, ullstr, strlen(ullstr));
+    unsigned long long ull3;
+    if (RedisModule_StringToULongLong(s3, &ull3) == REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid string successfully converted to unsigned long long");
+        RedisModule_FreeString(ctx, s3);
+        goto final;
+    }
+    RedisModule_FreeString(ctx, s3);
+    ullstr = "-1";
+    RedisModuleString *s4 = RedisModule_CreateString(ctx, ullstr, strlen(ullstr));
+    unsigned long long ull4;
+    if (RedisModule_StringToULongLong(s4, &ull4) == REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid string successfully converted to unsigned long long");
+        RedisModule_FreeString(ctx, s4);
+        goto final;
+    }
+    RedisModule_FreeString(ctx, s4);
+   
+    RedisModule_ReplyWithSimpleString(ctx, "ok");
+
+final:
+    RedisModule_FreeString(ctx, s1);
+    RedisModule_FreeString(ctx, s2);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"misc",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_KEY_MISS | REDISMODULE_NOTIFY_EXPIRED, KeySpace_NotificationModuleKeyMissExpired) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if (RedisModule_CreateCommand(ctx,"test.call_generic", test_call_generic,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.call_info", test_call_info,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.ld_conversion", test_ld_conv, "",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.ull_conversion", test_ull_conv, "",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.flushall", test_flushall,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.dbsize", test_dbsize,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.randomkey", test_randomkey,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.keyexists", test_keyexists,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.setlru", test_setlru,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.getlru", test_getlru,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.setlfu", test_setlfu,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.getlfu", test_getlfu,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.clientinfo", test_clientinfo,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.getname", test_getname,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.setname", test_setname,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.redisversion", test_redisversion,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.getclientcert", test_getclientcert,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.log_tsctx", test_log_tsctx,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    /* Add a command with ':' in it's name, so that we can check commandstats sanitization. */
+    if (RedisModule_CreateCommand(ctx,"test.weird:cmd", test_weird_cmd,"readonly",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.monotonic_time", test_monotonic_time,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.rm_call", test_rm_call,"allow-stale", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.rm_call_flags", test_rm_call_flags,"allow-stale", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.rm_call_replicate", test_rm_call_replicate,"allow-stale", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.silent_open_key", test_open_key_no_effects,"", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.get_n_events", test_get_n_events,"", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "test.clear_n_events", test_clear_n_events,"", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/moduleauthtwo.c b/tests/modules/moduleauthtwo.c
new file mode 100644
index 0000000..0a4f56b
--- /dev/null
+++ b/tests/modules/moduleauthtwo.c
@@ -0,0 +1,43 @@
+#include "redismodule.h"
+
+#include <string.h>
+
+/* This is a second sample module to validate that module authentication callbacks can be registered
+ * from multiple modules. */
+
+/* Non Blocking Module Auth callback / implementation. */
+int auth_cb(RedisModuleCtx *ctx, RedisModuleString *username, RedisModuleString *password, RedisModuleString **err) {
+    const char *user = RedisModule_StringPtrLen(username, NULL);
+    const char *pwd = RedisModule_StringPtrLen(password, NULL);
+    if (!strcmp(user,"foo") && !strcmp(pwd,"allow_two")) {
+        RedisModule_AuthenticateClientWithACLUser(ctx, "foo", 3, NULL, NULL, NULL);
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    else if (!strcmp(user,"foo") && !strcmp(pwd,"deny_two")) {
+        RedisModuleString *log = RedisModule_CreateString(ctx, "Module Auth", 11);
+        RedisModule_ACLAddLogEntryByUserName(ctx, username, log, REDISMODULE_ACL_LOG_AUTH);
+        RedisModule_FreeString(ctx, log);
+        const char *err_msg = "Auth denied by Misc Module.";
+        *err = RedisModule_CreateString(ctx, err_msg, strlen(err_msg));
+        return REDISMODULE_AUTH_HANDLED;
+    }
+    return REDISMODULE_AUTH_NOT_HANDLED;
+}
+
+int test_rm_register_auth_cb(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_RegisterAuthCallback(ctx, auth_cb);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"moduleauthtwo",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"testmoduletwo.rm_register_auth_cb", test_rm_register_auth_cb,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
\ No newline at end of file
diff --git a/tests/modules/moduleconfigs.c b/tests/modules/moduleconfigs.c
new file mode 100644
index 0000000..2c1737d
--- /dev/null
+++ b/tests/modules/moduleconfigs.c
@@ -0,0 +1,195 @@
+#include "redismodule.h"
+#include <strings.h>
+int mutable_bool_val;
+int immutable_bool_val;
+long long longval;
+long long memval;
+RedisModuleString *strval = NULL;
+int enumval;
+int flagsval;
+
+/* Series of get and set callbacks for each type of config, these rely on the privdata ptr
+ * to point to the config, and they register the configs as such. Note that one could also just
+ * use names if they wanted, and store anything in privdata. */
+int getBoolConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    return (*(int *)privdata);
+}
+
+int setBoolConfigCommand(const char *name, int new, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    *(int *)privdata = new;
+    return REDISMODULE_OK;
+}
+
+long long getNumericConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    return (*(long long *) privdata);
+}
+
+int setNumericConfigCommand(const char *name, long long new, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    *(long long *)privdata = new;
+    return REDISMODULE_OK;
+}
+
+RedisModuleString *getStringConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(privdata);
+    return strval;
+}
+int setStringConfigCommand(const char *name, RedisModuleString *new, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    REDISMODULE_NOT_USED(privdata);
+    size_t len;
+    if (!strcasecmp(RedisModule_StringPtrLen(new, &len), "rejectisfreed")) {
+        *err = RedisModule_CreateString(NULL, "Cannot set string to 'rejectisfreed'", 36);
+        return REDISMODULE_ERR;
+    }
+    if (strval) RedisModule_FreeString(NULL, strval);
+    RedisModule_RetainString(NULL, new);
+    strval = new;
+    return REDISMODULE_OK;
+}
+
+int getEnumConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(privdata);
+    return enumval;
+}
+
+int setEnumConfigCommand(const char *name, int val, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    REDISMODULE_NOT_USED(privdata);
+    enumval = val;
+    return REDISMODULE_OK;
+}
+
+int getFlagsConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(privdata);
+    return flagsval;
+}
+
+int setFlagsConfigCommand(const char *name, int val, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    REDISMODULE_NOT_USED(privdata);
+    flagsval = val;
+    return REDISMODULE_OK;
+}
+
+int boolApplyFunc(RedisModuleCtx *ctx, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(privdata);
+    if (mutable_bool_val && immutable_bool_val) {
+        *err = RedisModule_CreateString(NULL, "Bool configs cannot both be yes.", 32);
+        return REDISMODULE_ERR;
+    }
+    return REDISMODULE_OK;
+}
+
+int longlongApplyFunc(RedisModuleCtx *ctx, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(privdata);
+    if (longval == memval) {
+        *err = RedisModule_CreateString(NULL, "These configs cannot equal each other.", 38);
+        return REDISMODULE_ERR;
+    }
+    return REDISMODULE_OK;
+}
+
+int registerBlockCheck(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    int response_ok = 0;
+    int result = RedisModule_RegisterBoolConfig(ctx, "mutable_bool", 1, REDISMODULE_CONFIG_DEFAULT, getBoolConfigCommand, setBoolConfigCommand, boolApplyFunc, &mutable_bool_val);
+    response_ok |= (result == REDISMODULE_OK);
+
+    result = RedisModule_RegisterStringConfig(ctx, "string", "secret password", REDISMODULE_CONFIG_DEFAULT, getStringConfigCommand, setStringConfigCommand, NULL, NULL);
+    response_ok |= (result == REDISMODULE_OK);
+
+    const char *enum_vals[] = {"none", "five", "one", "two", "four"};
+    const int int_vals[] = {0, 5, 1, 2, 4};
+    result = RedisModule_RegisterEnumConfig(ctx, "enum", 1, REDISMODULE_CONFIG_DEFAULT, enum_vals, int_vals, 5, getEnumConfigCommand, setEnumConfigCommand, NULL, NULL);
+    response_ok |= (result == REDISMODULE_OK);
+
+    result = RedisModule_RegisterNumericConfig(ctx, "numeric", -1, REDISMODULE_CONFIG_DEFAULT, -5, 2000, getNumericConfigCommand, setNumericConfigCommand, longlongApplyFunc, &longval);
+    response_ok |= (result == REDISMODULE_OK);
+
+    result = RedisModule_LoadConfigs(ctx);
+    response_ok |= (result == REDISMODULE_OK);
+    
+    /* This validates that it's not possible to register/load configs outside OnLoad,
+     * thus returns an error if they succeed. */
+    if (response_ok) {
+        RedisModule_ReplyWithError(ctx, "UNEXPECTEDOK");
+    } else {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    }
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "moduleconfigs", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_RegisterBoolConfig(ctx, "mutable_bool", 1, REDISMODULE_CONFIG_DEFAULT, getBoolConfigCommand, setBoolConfigCommand, boolApplyFunc, &mutable_bool_val) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    /* Immutable config here. */
+    if (RedisModule_RegisterBoolConfig(ctx, "immutable_bool", 0, REDISMODULE_CONFIG_IMMUTABLE, getBoolConfigCommand, setBoolConfigCommand, boolApplyFunc, &immutable_bool_val) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    if (RedisModule_RegisterStringConfig(ctx, "string", "secret password", REDISMODULE_CONFIG_DEFAULT, getStringConfigCommand, setStringConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+
+    /* On the stack to make sure we're copying them. */
+    const char *enum_vals[] = {"none", "five", "one", "two", "four"};
+    const int int_vals[] = {0, 5, 1, 2, 4};
+
+    if (RedisModule_RegisterEnumConfig(ctx, "enum", 1, REDISMODULE_CONFIG_DEFAULT, enum_vals, int_vals, 5, getEnumConfigCommand, setEnumConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 5, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    /* Memory config here. */
+    if (RedisModule_RegisterNumericConfig(ctx, "memory_numeric", 1024, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_MEMORY, 0, 3000000, getNumericConfigCommand, setNumericConfigCommand, longlongApplyFunc, &memval) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    if (RedisModule_RegisterNumericConfig(ctx, "numeric", -1, REDISMODULE_CONFIG_DEFAULT, -5, 2000, getNumericConfigCommand, setNumericConfigCommand, longlongApplyFunc, &longval) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    size_t len;
+    if (argc && !strcasecmp(RedisModule_StringPtrLen(argv[0], &len), "noload")) {
+        return REDISMODULE_OK;
+    } else if (RedisModule_LoadConfigs(ctx) == REDISMODULE_ERR) {
+        if (strval) {
+            RedisModule_FreeString(ctx, strval);
+            strval = NULL;
+        }
+        return REDISMODULE_ERR;
+    }
+    /* Creates a command which registers configs outside OnLoad() function. */
+    if (RedisModule_CreateCommand(ctx,"block.register.configs.outside.onload", registerBlockCheck, "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+  
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    REDISMODULE_NOT_USED(ctx);
+    if (strval) {
+        RedisModule_FreeString(ctx, strval);
+        strval = NULL;
+    }
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/moduleconfigstwo.c b/tests/modules/moduleconfigstwo.c
new file mode 100644
index 0000000..c0e8f91
--- /dev/null
+++ b/tests/modules/moduleconfigstwo.c
@@ -0,0 +1,39 @@
+#include "redismodule.h"
+#include <strings.h>
+
+/* Second module configs module, for testing.
+ * Need to make sure that multiple modules with configs don't interfere with each other */
+int bool_config;
+
+int getBoolConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(privdata);
+    if (!strcasecmp(name, "test")) {
+        return bool_config;
+    }
+    return 0;
+}
+
+int setBoolConfigCommand(const char *name, int new, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(privdata);
+    REDISMODULE_NOT_USED(err);
+    if (!strcasecmp(name, "test")) {
+        bool_config = new;
+        return REDISMODULE_OK;
+    }
+    return REDISMODULE_ERR;
+}
+
+/* No arguments are expected */ 
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "configs", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_RegisterBoolConfig(ctx, "test", 1, REDISMODULE_CONFIG_DEFAULT, getBoolConfigCommand, setBoolConfigCommand, NULL, &argc) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    if (RedisModule_LoadConfigs(ctx) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    return REDISMODULE_OK;
+}
\ No newline at end of file
diff --git a/tests/modules/postnotifications.c b/tests/modules/postnotifications.c
new file mode 100644
index 0000000..b4a97cb
--- /dev/null
+++ b/tests/modules/postnotifications.c
@@ -0,0 +1,303 @@
+/* This module is used to test the server post keyspace jobs API.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2020, Meir Shpilraien <meir at redislabs dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* This module allow to verify 'RedisModule_AddPostNotificationJob' by registering to 3
+ * key space event:
+ * * STRINGS - the module register to all strings notifications and set post notification job
+ *             that increase a counter indicating how many times the string key was changed.
+ *             In addition, it increase another counter that counts the total changes that
+ *             was made on all strings keys.
+ * * EXPIRED - the module register to expired event and set post notification job that that
+ *             counts the total number of expired events.
+ * * EVICTED - the module register to evicted event and set post notification job that that
+ *             counts the total number of evicted events.
+ *
+ * In addition, the module register a new command, 'postnotification.async_set', that performs a set
+ * command from a background thread. This allows to check the 'RedisModule_AddPostNotificationJob' on
+ * notifications that was triggered on a background thread. */
+
+#define _BSD_SOURCE
+#define _DEFAULT_SOURCE /* For usleep */
+
+#include "redismodule.h"
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <pthread.h>
+
+static void KeySpace_PostNotificationStringFreePD(void *pd) {
+    RedisModule_FreeString(NULL, pd);
+}
+
+static void KeySpace_PostNotificationReadKey(RedisModuleCtx *ctx, void *pd) {
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "get", "!s", pd);
+    RedisModule_FreeCallReply(rep);
+}
+
+static void KeySpace_PostNotificationString(RedisModuleCtx *ctx, void *pd) {
+    REDISMODULE_NOT_USED(ctx);
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "incr", "!s", pd);
+    RedisModule_FreeCallReply(rep);
+}
+
+static int KeySpace_NotificationExpired(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    REDISMODULE_NOT_USED(key);
+
+    RedisModuleString *new_key = RedisModule_CreateString(NULL, "expired", 7);
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationEvicted(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    REDISMODULE_NOT_USED(key);
+
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+
+    if (strncmp(key_str, "evicted", 7) == 0) {
+        return REDISMODULE_OK; /* do not count the evicted key */
+    }
+
+    if (strncmp(key_str, "before_evicted", 14) == 0) {
+        return REDISMODULE_OK; /* do not count the before_evicted key */
+    }
+
+    RedisModuleString *new_key = RedisModule_CreateString(NULL, "evicted", 7);
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NotificationString(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+
+    if (strncmp(key_str, "string_", 7) != 0) {
+        return REDISMODULE_OK;
+    }
+
+    if (strcmp(key_str, "string_total") == 0) {
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleString *new_key;
+    if (strncmp(key_str, "string_changed{", 15) == 0) {
+        new_key = RedisModule_CreateString(NULL, "string_total", 12);
+    } else {
+        new_key = RedisModule_CreateStringPrintf(NULL, "string_changed{%s}", key_str);
+    }
+
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationString, new_key, KeySpace_PostNotificationStringFreePD);
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_LazyExpireInsidePostNotificationJob(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+
+    if (strncmp(key_str, "read_", 5) != 0) {
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleString *new_key = RedisModule_CreateString(NULL, key_str + 5, strlen(key_str) - 5);;
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_PostNotificationReadKey, new_key, KeySpace_PostNotificationStringFreePD);
+    return REDISMODULE_OK;
+}
+
+static int KeySpace_NestedNotification(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key){
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+
+    const char *key_str = RedisModule_StringPtrLen(key, NULL);
+
+    if (strncmp(key_str, "write_sync_", 11) != 0) {
+        return REDISMODULE_OK;
+    }
+
+    /* This test was only meant to check REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS.
+     * In general it is wrong and discourage to perform any writes inside a notification callback.  */
+    RedisModuleString *new_key = RedisModule_CreateString(NULL, key_str + 11, strlen(key_str) - 11);;
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "set", "!sc", new_key, "1");
+    RedisModule_FreeCallReply(rep);
+    RedisModule_FreeString(NULL, new_key);
+    return REDISMODULE_OK;
+}
+
+static void *KeySpace_PostNotificationsAsyncSetInner(void *arg) {
+    RedisModuleBlockedClient *bc = arg;
+    RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(bc);
+    RedisModule_ThreadSafeContextLock(ctx);
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "set", "!cc", "string_x", "1");
+    RedisModule_ThreadSafeContextUnlock(ctx);
+    RedisModule_ReplyWithCallReply(ctx, rep);
+    RedisModule_FreeCallReply(rep);
+
+    RedisModule_UnblockClient(bc, NULL);
+    RedisModule_FreeThreadSafeContext(ctx);
+    return NULL;
+}
+
+static int KeySpace_PostNotificationsAsyncSet(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1)
+        return RedisModule_WrongArity(ctx);
+
+    pthread_t tid;
+    RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,NULL,NULL,NULL,0);
+
+    if (pthread_create(&tid,NULL,KeySpace_PostNotificationsAsyncSetInner,bc) != 0) {
+        RedisModule_AbortBlock(bc);
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    }
+    return REDISMODULE_OK;
+}
+
+typedef struct KeySpace_EventPostNotificationCtx {
+    RedisModuleString *triggered_on;
+    RedisModuleString *new_key;
+} KeySpace_EventPostNotificationCtx;
+
+static void KeySpace_ServerEventPostNotificationFree(void *pd) {
+    KeySpace_EventPostNotificationCtx *pn_ctx = pd;
+    RedisModule_FreeString(NULL, pn_ctx->new_key);
+    RedisModule_FreeString(NULL, pn_ctx->triggered_on);
+    RedisModule_Free(pn_ctx);
+}
+
+static void KeySpace_ServerEventPostNotification(RedisModuleCtx *ctx, void *pd) {
+    REDISMODULE_NOT_USED(ctx);
+    KeySpace_EventPostNotificationCtx *pn_ctx = pd;
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "lpush", "!ss", pn_ctx->new_key, pn_ctx->triggered_on);
+    RedisModule_FreeCallReply(rep);
+}
+
+static void KeySpace_ServerEventCallback(RedisModuleCtx *ctx, RedisModuleEvent eid, uint64_t subevent, void *data) {
+    REDISMODULE_NOT_USED(eid);
+    REDISMODULE_NOT_USED(data);
+    if (subevent > 3) {
+        RedisModule_Log(ctx, "warning", "Got an unexpected subevent '%ld'", subevent);
+        return;
+    }
+    static const char* events[] = {
+            "before_deleted",
+            "before_expired",
+            "before_evicted",
+            "before_overwritten",
+    };
+
+    const RedisModuleString *key_name = RedisModule_GetKeyNameFromModuleKey(((RedisModuleKeyInfo*)data)->key);
+    const char *key_str = RedisModule_StringPtrLen(key_name, NULL);
+
+    for (int i = 0 ; i < 4 ; ++i) {
+        const char *event = events[i];
+        if (strncmp(key_str, event , strlen(event)) == 0) {
+            return; /* don't log any event on our tracking keys */
+        }
+    }
+
+    KeySpace_EventPostNotificationCtx *pn_ctx = RedisModule_Alloc(sizeof(*pn_ctx));
+    pn_ctx->triggered_on = RedisModule_HoldString(NULL, (RedisModuleString*)key_name);
+    pn_ctx->new_key = RedisModule_CreateString(NULL, events[subevent], strlen(events[subevent]));
+    RedisModule_AddPostNotificationJob(ctx, KeySpace_ServerEventPostNotification, pn_ctx, KeySpace_ServerEventPostNotificationFree);
+}
+
+/* This function must be present on each Redis module. It is used in order to
+ * register the commands into the Redis server. */
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"postnotifications",1,REDISMODULE_APIVER_1) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    if (!(RedisModule_GetModuleOptionsAll() & REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS)) {
+        return REDISMODULE_ERR;
+    }
+
+    int with_key_events = 0;
+    if (argc >= 1) {
+        const char *arg = RedisModule_StringPtrLen(argv[0], 0);
+        if (strcmp(arg, "with_key_events") == 0) {
+            with_key_events = 1;
+        }
+    }
+
+    RedisModule_SetModuleOptions(ctx, REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS);
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NotificationString) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_LazyExpireInsidePostNotificationJob) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_STRING, KeySpace_NestedNotification) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_EXPIRED, KeySpace_NotificationExpired) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if(RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_EVICTED, KeySpace_NotificationEvicted) != REDISMODULE_OK){
+        return REDISMODULE_ERR;
+    }
+
+    if (with_key_events) {
+        if(RedisModule_SubscribeToServerEvent(ctx, RedisModuleEvent_Key, KeySpace_ServerEventCallback) != REDISMODULE_OK){
+            return REDISMODULE_ERR;
+        }
+    }
+
+    if (RedisModule_CreateCommand(ctx, "postnotification.async_set", KeySpace_PostNotificationsAsyncSet,
+                                      "write", 0, 0, 0) == REDISMODULE_ERR){
+        return REDISMODULE_ERR;
+    }
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    REDISMODULE_NOT_USED(ctx);
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/propagate.c b/tests/modules/propagate.c
new file mode 100644
index 0000000..d5132a5
--- /dev/null
+++ b/tests/modules/propagate.c
@@ -0,0 +1,403 @@
+/* This module is used to test the propagation (replication + AOF) of
+ * commands, via the RedisModule_Replicate() interface, in asynchronous
+ * contexts, such as callbacks not implementing commands, and thread safe
+ * contexts.
+ *
+ * We create a timer callback and a threads using a thread safe context.
+ * Using both we try to propagate counters increments, and later we check
+ * if the replica contains the changes as expected.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2019, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "redismodule.h"
+#include <pthread.h>
+#include <errno.h>
+
+#define UNUSED(V) ((void) V)
+
+RedisModuleCtx *detached_ctx = NULL;
+
+static int KeySpace_NotificationGeneric(RedisModuleCtx *ctx, int type, const char *event, RedisModuleString *key) {
+    REDISMODULE_NOT_USED(type);
+    REDISMODULE_NOT_USED(event);
+    REDISMODULE_NOT_USED(key);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, "INCR", "c!", "notifications");
+    RedisModule_FreeCallReply(rep);
+
+    return REDISMODULE_OK;
+}
+
+/* Timer callback. */
+void timerHandler(RedisModuleCtx *ctx, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(data);
+
+    static int times = 0;
+
+    RedisModule_Replicate(ctx,"INCR","c","timer");
+    times++;
+
+    if (times < 3)
+        RedisModule_CreateTimer(ctx,100,timerHandler,NULL);
+    else
+        times = 0;
+}
+
+int propagateTestTimerCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleTimerID timer_id =
+        RedisModule_CreateTimer(ctx,100,timerHandler,NULL);
+    REDISMODULE_NOT_USED(timer_id);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+/* Timer callback. */
+void timerNestedHandler(RedisModuleCtx *ctx, void *data) {
+    int repl = (long long)data;
+
+    /* The goal is the trigger a module command that calls RM_Replicate
+     * in order to test MULTI/EXEC structure */
+    RedisModule_Replicate(ctx,"INCRBY","cc","timer-nested-start","1");
+    RedisModuleCallReply *reply = RedisModule_Call(ctx,"propagate-test.nested", repl? "!" : "");
+    RedisModule_FreeCallReply(reply);
+    reply = RedisModule_Call(ctx, "INCR", repl? "c!" : "c", "timer-nested-middle");
+    RedisModule_FreeCallReply(reply);
+    RedisModule_Replicate(ctx,"INCRBY","cc","timer-nested-end","1");
+}
+
+int propagateTestTimerNestedCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleTimerID timer_id =
+        RedisModule_CreateTimer(ctx,100,timerNestedHandler,(void*)0);
+    REDISMODULE_NOT_USED(timer_id);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+int propagateTestTimerNestedReplCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleTimerID timer_id =
+        RedisModule_CreateTimer(ctx,100,timerNestedHandler,(void*)1);
+    REDISMODULE_NOT_USED(timer_id);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+void timerHandlerMaxmemory(RedisModuleCtx *ctx, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(data);
+
+    RedisModuleCallReply *reply = RedisModule_Call(ctx,"SETEX","ccc!","timer-maxmemory-volatile-start","100","1");
+    RedisModule_FreeCallReply(reply);
+    reply = RedisModule_Call(ctx, "CONFIG", "ccc!", "SET", "maxmemory", "1");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_Replicate(ctx, "INCR", "c", "timer-maxmemory-middle");
+
+    reply = RedisModule_Call(ctx,"SETEX","ccc!","timer-maxmemory-volatile-end","100","1");
+    RedisModule_FreeCallReply(reply);
+}
+
+int propagateTestTimerMaxmemoryCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleTimerID timer_id =
+        RedisModule_CreateTimer(ctx,100,timerHandlerMaxmemory,(void*)1);
+    REDISMODULE_NOT_USED(timer_id);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+void timerHandlerEval(RedisModuleCtx *ctx, void *data) {
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(data);
+
+    RedisModuleCallReply *reply = RedisModule_Call(ctx,"INCRBY","cc!","timer-eval-start","1");
+    RedisModule_FreeCallReply(reply);
+    reply = RedisModule_Call(ctx, "EVAL", "cccc!", "redis.call('set',KEYS[1],ARGV[1])", "1", "foo", "bar");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_Replicate(ctx, "INCR", "c", "timer-eval-middle");
+
+    reply = RedisModule_Call(ctx,"INCRBY","cc!","timer-eval-end","1");
+    RedisModule_FreeCallReply(reply);
+}
+
+int propagateTestTimerEvalCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleTimerID timer_id =
+        RedisModule_CreateTimer(ctx,100,timerHandlerEval,(void*)1);
+    REDISMODULE_NOT_USED(timer_id);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+/* The thread entry point. */
+void *threadMain(void *arg) {
+    REDISMODULE_NOT_USED(arg);
+    RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(NULL);
+    RedisModule_SelectDb(ctx,9); /* Tests ran in database number 9. */
+    for (int i = 0; i < 3; i++) {
+        RedisModule_ThreadSafeContextLock(ctx);
+        RedisModule_Replicate(ctx,"INCR","c","a-from-thread");
+        RedisModuleCallReply *reply = RedisModule_Call(ctx,"INCR","c!","thread-call");
+        RedisModule_FreeCallReply(reply);
+        RedisModule_Replicate(ctx,"INCR","c","b-from-thread");
+        RedisModule_ThreadSafeContextUnlock(ctx);
+    }
+    RedisModule_FreeThreadSafeContext(ctx);
+    return NULL;
+}
+
+int propagateTestThreadCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    pthread_t tid;
+    if (pthread_create(&tid,NULL,threadMain,NULL) != 0)
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    REDISMODULE_NOT_USED(tid);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+/* The thread entry point. */
+void *threadDetachedMain(void *arg) {
+    REDISMODULE_NOT_USED(arg);
+    RedisModule_SelectDb(detached_ctx,9); /* Tests ran in database number 9. */
+
+    RedisModule_ThreadSafeContextLock(detached_ctx);
+    RedisModule_Replicate(detached_ctx,"INCR","c","thread-detached-before");
+    RedisModuleCallReply *reply = RedisModule_Call(detached_ctx,"INCR","c!","thread-detached-1");
+    RedisModule_FreeCallReply(reply);
+    reply = RedisModule_Call(detached_ctx,"INCR","c!","thread-detached-2");
+    RedisModule_FreeCallReply(reply);
+    RedisModule_Replicate(detached_ctx,"INCR","c","thread-detached-after");
+    RedisModule_ThreadSafeContextUnlock(detached_ctx);
+
+    return NULL;
+}
+
+int propagateTestDetachedThreadCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    pthread_t tid;
+    if (pthread_create(&tid,NULL,threadDetachedMain,NULL) != 0)
+        return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");
+    REDISMODULE_NOT_USED(tid);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+int propagateTestSimpleCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    /* Replicate two commands to test MULTI/EXEC wrapping. */
+    RedisModule_Replicate(ctx,"INCR","c","counter-1");
+    RedisModule_Replicate(ctx,"INCR","c","counter-2");
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+int propagateTestMixedCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleCallReply *reply;
+
+    /* This test mixes multiple propagation systems. */
+    reply = RedisModule_Call(ctx, "INCR", "c!", "using-call");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_Replicate(ctx,"INCR","c","counter-1");
+    RedisModule_Replicate(ctx,"INCR","c","counter-2");
+
+    reply = RedisModule_Call(ctx, "INCR", "c!", "after-call");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+int propagateTestNestedCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleCallReply *reply;
+
+    /* This test mixes multiple propagation systems. */
+    reply = RedisModule_Call(ctx, "INCR", "c!", "using-call");
+    RedisModule_FreeCallReply(reply);
+
+    reply = RedisModule_Call(ctx,"propagate-test.simple", "!");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_Replicate(ctx,"INCR","c","counter-3");
+    RedisModule_Replicate(ctx,"INCR","c","counter-4");
+
+    reply = RedisModule_Call(ctx, "INCR", "c!", "after-call");
+    RedisModule_FreeCallReply(reply);
+
+    reply = RedisModule_Call(ctx, "INCR", "c!", "before-call-2");
+    RedisModule_FreeCallReply(reply);
+
+    reply = RedisModule_Call(ctx, "keyspace.incr_case1", "c!", "asdf"); /* Propagates INCR */
+    RedisModule_FreeCallReply(reply);
+
+    reply = RedisModule_Call(ctx, "keyspace.del_key_copy", "c!", "asdf"); /* Propagates DEL */
+    RedisModule_FreeCallReply(reply);
+
+    reply = RedisModule_Call(ctx, "INCR", "c!", "after-call-2");
+    RedisModule_FreeCallReply(reply);
+
+    RedisModule_ReplyWithSimpleString(ctx,"OK");
+    return REDISMODULE_OK;
+}
+
+int propagateTestIncr(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argc);
+    RedisModuleCallReply *reply;
+
+    /* This test propagates the module command, not the INCR it executes. */
+    reply = RedisModule_Call(ctx, "INCR", "s", argv[1]);
+    RedisModule_ReplyWithCallReply(ctx,reply);
+    RedisModule_FreeCallReply(reply);
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"propagate-test",1,REDISMODULE_APIVER_1)
+            == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    detached_ctx = RedisModule_GetDetachedThreadSafeContext(ctx);
+
+    if (RedisModule_SubscribeToKeyspaceEvents(ctx, REDISMODULE_NOTIFY_ALL, KeySpace_NotificationGeneric) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.timer",
+                propagateTestTimerCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.timer-nested",
+                propagateTestTimerNestedCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.timer-nested-repl",
+                propagateTestTimerNestedReplCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.timer-maxmemory",
+                propagateTestTimerMaxmemoryCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.timer-eval",
+                propagateTestTimerEvalCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.thread",
+                propagateTestThreadCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.detached-thread",
+                propagateTestDetachedThreadCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.simple",
+                propagateTestSimpleCommand,
+                "",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.mixed",
+                propagateTestMixedCommand,
+                "write",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.nested",
+                propagateTestNestedCommand,
+                "write",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"propagate-test.incr",
+                propagateTestIncr,
+                "write",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    UNUSED(ctx);
+
+    if (detached_ctx)
+        RedisModule_FreeThreadSafeContext(detached_ctx);
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/publish.c b/tests/modules/publish.c
new file mode 100644
index 0000000..ff276d8
--- /dev/null
+++ b/tests/modules/publish.c
@@ -0,0 +1,57 @@
+#include "redismodule.h"
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+
+#define UNUSED(V) ((void) V)
+
+int cmd_publish_classic_multi(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc < 3)
+        return RedisModule_WrongArity(ctx);
+    RedisModule_ReplyWithArray(ctx, argc-2);
+    for (int i = 2; i < argc; i++) {
+        int receivers = RedisModule_PublishMessage(ctx, argv[1], argv[i]);
+        RedisModule_ReplyWithLongLong(ctx, receivers);
+    }
+    return REDISMODULE_OK;
+}
+
+int cmd_publish_classic(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 3)
+        return RedisModule_WrongArity(ctx);
+    
+    int receivers = RedisModule_PublishMessage(ctx, argv[1], argv[2]);
+    RedisModule_ReplyWithLongLong(ctx, receivers);
+    return REDISMODULE_OK;
+}
+
+int cmd_publish_shard(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 3)
+        return RedisModule_WrongArity(ctx);
+    
+    int receivers = RedisModule_PublishMessageShard(ctx, argv[1], argv[2]);
+    RedisModule_ReplyWithLongLong(ctx, receivers);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    
+    if (RedisModule_Init(ctx,"publish",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"publish.classic",cmd_publish_classic,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"publish.classic_multi",cmd_publish_classic_multi,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"publish.shard",cmd_publish_shard,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+        
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/rdbloadsave.c b/tests/modules/rdbloadsave.c
new file mode 100644
index 0000000..687269a
--- /dev/null
+++ b/tests/modules/rdbloadsave.c
@@ -0,0 +1,162 @@
+#include "redismodule.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <memory.h>
+#include <errno.h>
+
+/* Sanity tests to verify inputs and return values. */
+int sanity(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    RedisModuleRdbStream *s = RedisModule_RdbStreamCreateFromFile("dbnew.rdb");
+
+    /* NULL stream should fail. */
+    if (RedisModule_RdbLoad(ctx, NULL, 0) == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    /* Invalid flags should fail. */
+    if (RedisModule_RdbLoad(ctx, s, 188) == REDISMODULE_OK || errno != EINVAL) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    /* Missing file should fail. */
+    if (RedisModule_RdbLoad(ctx, s, 0) == REDISMODULE_OK || errno != ENOENT) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    /* Save RDB file. */
+    if (RedisModule_RdbSave(ctx, s, 0) != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    /* Load the saved RDB file. */
+    if (RedisModule_RdbLoad(ctx, s, 0) != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+ out:
+    RedisModule_RdbStreamFree(s);
+    return REDISMODULE_OK;
+}
+
+int cmd_rdbsave(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    size_t len;
+    const char *filename = RedisModule_StringPtrLen(argv[1], &len);
+
+    char tmp[len + 1];
+    memcpy(tmp, filename, len);
+    tmp[len] = '\0';
+
+    RedisModuleRdbStream *stream = RedisModule_RdbStreamCreateFromFile(tmp);
+
+    if (RedisModule_RdbSave(ctx, stream, 0) != REDISMODULE_OK || errno != 0) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        goto out;
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+out:
+    RedisModule_RdbStreamFree(stream);
+    return REDISMODULE_OK;
+}
+
+/* Fork before calling RM_RdbSave(). */
+int cmd_rdbsave_fork(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    size_t len;
+    const char *filename = RedisModule_StringPtrLen(argv[1], &len);
+
+    char tmp[len + 1];
+    memcpy(tmp, filename, len);
+    tmp[len] = '\0';
+
+    int fork_child_pid = RedisModule_Fork(NULL, NULL);
+    if (fork_child_pid < 0) {
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        return REDISMODULE_OK;
+    } else if (fork_child_pid > 0) {
+        /* parent */
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleRdbStream *stream = RedisModule_RdbStreamCreateFromFile(tmp);
+
+    int ret = 0;
+    if (RedisModule_RdbSave(ctx, stream, 0) != REDISMODULE_OK) {
+        ret = errno;
+    }
+    RedisModule_RdbStreamFree(stream);
+
+    RedisModule_ExitFromChild(ret);
+    return REDISMODULE_OK;
+}
+
+int cmd_rdbload(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    size_t len;
+    const char *filename = RedisModule_StringPtrLen(argv[1], &len);
+
+    char tmp[len + 1];
+    memcpy(tmp, filename, len);
+    tmp[len] = '\0';
+
+    RedisModuleRdbStream *stream = RedisModule_RdbStreamCreateFromFile(tmp);
+
+    if (RedisModule_RdbLoad(ctx, stream, 0) != REDISMODULE_OK || errno != 0) {
+        RedisModule_RdbStreamFree(stream);
+        RedisModule_ReplyWithError(ctx, strerror(errno));
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_RdbStreamFree(stream);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "rdbloadsave", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "test.sanity", sanity, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "test.rdbsave", cmd_rdbsave, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "test.rdbsave_fork", cmd_rdbsave_fork, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "test.rdbload", cmd_rdbload, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/reply.c b/tests/modules/reply.c
new file mode 100644
index 0000000..c5baa66
--- /dev/null
+++ b/tests/modules/reply.c
@@ -0,0 +1,214 @@
+/* 
+ * A module the tests RM_ReplyWith family of commands
+ */
+
+#include "redismodule.h"
+#include <math.h>
+
+int rw_string(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    return RedisModule_ReplyWithString(ctx, argv[1]);
+}
+
+int rw_cstring(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1) return RedisModule_WrongArity(ctx);
+
+    return RedisModule_ReplyWithSimpleString(ctx, "A simple string");
+}
+
+int rw_int(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long long integer;
+    if (RedisModule_StringToLongLong(argv[1], &integer) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as an integer");
+
+    return RedisModule_ReplyWithLongLong(ctx, integer);
+}
+
+/* When one argument is given, it is returned as a double,
+ * when two arguments are given, it returns a/b. */
+int rw_double(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc==1)
+        return RedisModule_ReplyWithDouble(ctx, NAN);
+
+    if (argc != 2 && argc != 3) return RedisModule_WrongArity(ctx);
+
+    double dbl, dbl2;
+    if (RedisModule_StringToDouble(argv[1], &dbl) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a double");
+    if (argc == 3) {
+        if (RedisModule_StringToDouble(argv[2], &dbl2) != REDISMODULE_OK)
+            return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a double");
+        dbl /= dbl2;
+    }
+
+    return RedisModule_ReplyWithDouble(ctx, dbl);
+}
+
+int rw_longdouble(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long double longdbl;
+    if (RedisModule_StringToLongDouble(argv[1], &longdbl) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a double");
+
+    return RedisModule_ReplyWithLongDouble(ctx, longdbl);
+}
+
+int rw_bignumber(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    size_t bignum_len;
+    const char *bignum_str = RedisModule_StringPtrLen(argv[1], &bignum_len);
+
+    return RedisModule_ReplyWithBigNumber(ctx, bignum_str, bignum_len);
+}
+
+int rw_array(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long long integer;
+    if (RedisModule_StringToLongLong(argv[1], &integer) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a integer");
+
+    RedisModule_ReplyWithArray(ctx, integer);
+    for (int i = 0; i < integer; ++i) {
+        RedisModule_ReplyWithLongLong(ctx, i);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int rw_map(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long long integer;
+    if (RedisModule_StringToLongLong(argv[1], &integer) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a integer");
+
+    RedisModule_ReplyWithMap(ctx, integer);
+    for (int i = 0; i < integer; ++i) {
+        RedisModule_ReplyWithLongLong(ctx, i);
+        RedisModule_ReplyWithDouble(ctx, i * 1.5);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int rw_set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long long integer;
+    if (RedisModule_StringToLongLong(argv[1], &integer) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a integer");
+
+    RedisModule_ReplyWithSet(ctx, integer);
+    for (int i = 0; i < integer; ++i) {
+        RedisModule_ReplyWithLongLong(ctx, i);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int rw_attribute(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    long long integer;
+    if (RedisModule_StringToLongLong(argv[1], &integer) != REDISMODULE_OK)
+        return RedisModule_ReplyWithError(ctx, "Arg cannot be parsed as a integer");
+
+    if (RedisModule_ReplyWithAttribute(ctx, integer) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx, "Attributes aren't supported by RESP 2");
+    }
+
+    for (int i = 0; i < integer; ++i) {
+        RedisModule_ReplyWithLongLong(ctx, i);
+        RedisModule_ReplyWithDouble(ctx, i * 1.5);
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int rw_bool(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1) return RedisModule_WrongArity(ctx);
+
+    RedisModule_ReplyWithArray(ctx, 2);
+    RedisModule_ReplyWithBool(ctx, 0);
+    return RedisModule_ReplyWithBool(ctx, 1);
+}
+
+int rw_null(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1) return RedisModule_WrongArity(ctx);
+
+    return RedisModule_ReplyWithNull(ctx);
+}
+
+int rw_error(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1) return RedisModule_WrongArity(ctx);
+
+    return RedisModule_ReplyWithError(ctx, "An error");
+}
+
+int rw_error_format(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+
+    return RedisModule_ReplyWithErrorFormat(ctx,
+                                            RedisModule_StringPtrLen(argv[1], NULL),
+                                            RedisModule_StringPtrLen(argv[2], NULL));
+}
+
+int rw_verbatim(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+
+    size_t verbatim_len;
+    const char *verbatim_str = RedisModule_StringPtrLen(argv[1], &verbatim_len);
+
+    return RedisModule_ReplyWithVerbatimString(ctx, verbatim_str, verbatim_len);
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "replywith", 1, REDISMODULE_APIVER_1) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"rw.string",rw_string,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.cstring",rw_cstring,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.bignumber",rw_bignumber,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.int",rw_int,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.double",rw_double,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.longdouble",rw_longdouble,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.array",rw_array,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.map",rw_map,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.attribute",rw_attribute,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.set",rw_set,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.bool",rw_bool,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.null",rw_null,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.error",rw_error,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.error_format",rw_error_format,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"rw.verbatim",rw_verbatim,"",0,0,0) != REDISMODULE_OK)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/scan.c b/tests/modules/scan.c
new file mode 100644
index 0000000..1723d30
--- /dev/null
+++ b/tests/modules/scan.c
@@ -0,0 +1,121 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+
+typedef struct {
+    size_t nkeys;
+} scan_strings_pd;
+
+void scan_strings_callback(RedisModuleCtx *ctx, RedisModuleString* keyname, RedisModuleKey* key, void *privdata) {
+    scan_strings_pd* pd = privdata;
+    int was_opened = 0;
+    if (!key) {
+        key = RedisModule_OpenKey(ctx, keyname, REDISMODULE_READ);
+        was_opened = 1;
+    }
+
+    if (RedisModule_KeyType(key) == REDISMODULE_KEYTYPE_STRING) {
+        size_t len;
+        char * data = RedisModule_StringDMA(key, &len, REDISMODULE_READ);
+        RedisModule_ReplyWithArray(ctx, 2);
+        RedisModule_ReplyWithString(ctx, keyname);
+        RedisModule_ReplyWithStringBuffer(ctx, data, len);
+        pd->nkeys++;
+    }
+    if (was_opened)
+        RedisModule_CloseKey(key);
+}
+
+int scan_strings(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    scan_strings_pd pd = {
+        .nkeys = 0,
+    };
+
+    RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
+
+    RedisModuleScanCursor* cursor = RedisModule_ScanCursorCreate();
+    while(RedisModule_Scan(ctx, cursor, scan_strings_callback, &pd));
+    RedisModule_ScanCursorDestroy(cursor);
+
+    RedisModule_ReplySetArrayLength(ctx, pd.nkeys);
+    return REDISMODULE_OK;
+}
+
+typedef struct {
+    RedisModuleCtx *ctx;
+    size_t nreplies;
+} scan_key_pd;
+
+void scan_key_callback(RedisModuleKey *key, RedisModuleString* field, RedisModuleString* value, void *privdata) {
+    REDISMODULE_NOT_USED(key);
+    scan_key_pd* pd = privdata;
+    RedisModule_ReplyWithArray(pd->ctx, 2);
+    size_t fieldCStrLen;
+
+    // The implementation of RedisModuleString is robj with lots of encodings.
+    // We want to make sure the robj that passes to this callback in
+    // String encoded, this is why we use RedisModule_StringPtrLen and
+    // RedisModule_ReplyWithStringBuffer instead of directly use
+    // RedisModule_ReplyWithString.
+    const char* fieldCStr = RedisModule_StringPtrLen(field, &fieldCStrLen);
+    RedisModule_ReplyWithStringBuffer(pd->ctx, fieldCStr, fieldCStrLen);
+    if(value){
+        size_t valueCStrLen;
+        const char* valueCStr = RedisModule_StringPtrLen(value, &valueCStrLen);
+        RedisModule_ReplyWithStringBuffer(pd->ctx, valueCStr, valueCStrLen);
+    } else {
+        RedisModule_ReplyWithNull(pd->ctx);
+    }
+
+    pd->nreplies++;
+}
+
+int scan_key(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    scan_key_pd pd = {
+        .ctx = ctx,
+        .nreplies = 0,
+    };
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    if (!key) {
+        RedisModule_ReplyWithError(ctx, "not found");
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_ARRAY_LEN);
+
+    RedisModuleScanCursor* cursor = RedisModule_ScanCursorCreate();
+    while(RedisModule_ScanKey(key, cursor, scan_key_callback, &pd));
+    RedisModule_ScanCursorDestroy(cursor);
+
+    RedisModule_ReplySetArrayLength(ctx, pd.nreplies);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "scan", 1, REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "scan.scan_strings", scan_strings, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "scan.scan_key", scan_key, "", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
+
+
diff --git a/tests/modules/stream.c b/tests/modules/stream.c
new file mode 100644
index 0000000..65762a3
--- /dev/null
+++ b/tests/modules/stream.c
@@ -0,0 +1,258 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+#include <errno.h>
+
+/* Command which adds a stream entry with automatic ID, like XADD *.
+ *
+ * Syntax: STREAM.ADD key field1 value1 [ field2 value2 ... ]
+ *
+ * The response is the ID of the added stream entry or an error message.
+ */
+int stream_add(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 2 || argc % 2 != 0) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    RedisModuleStreamID id;
+    if (RedisModule_StreamAdd(key, REDISMODULE_STREAM_ADD_AUTOID, &id,
+                              &argv[2], (argc-2)/2) == REDISMODULE_OK) {
+        RedisModuleString *id_str = RedisModule_CreateStringFromStreamID(ctx, &id);
+        RedisModule_ReplyWithString(ctx, id_str);
+        RedisModule_FreeString(ctx, id_str);
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR StreamAdd failed");
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* Command which adds a stream entry N times.
+ *
+ * Syntax: STREAM.ADD key N field1 value1 [ field2 value2 ... ]
+ *
+ * Returns the number of successfully added entries.
+ */
+int stream_addn(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3 || argc % 2 == 0) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long n, i;
+    if (RedisModule_StringToLongLong(argv[2], &n) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx, "N must be a number");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    for (i = 0; i < n; i++) {
+        if (RedisModule_StreamAdd(key, REDISMODULE_STREAM_ADD_AUTOID, NULL,
+                                  &argv[3], (argc-3)/2) == REDISMODULE_ERR)
+            break;
+    }
+    RedisModule_ReplyWithLongLong(ctx, i);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* STREAM.DELETE key stream-id */
+int stream_delete(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    RedisModuleStreamID id;
+    if (RedisModule_StringToStreamID(argv[2], &id) != REDISMODULE_OK) {
+        return RedisModule_ReplyWithError(ctx, "Invalid stream ID");
+    }
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    if (RedisModule_StreamDelete(key, &id) == REDISMODULE_OK) {
+        RedisModule_ReplyWithSimpleString(ctx, "OK");
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR StreamDelete failed");
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/* STREAM.RANGE key start-id end-id
+ *
+ * Returns an array of stream items. Each item is an array on the form
+ * [stream-id, [field1, value1, field2, value2, ...]].
+ *
+ * A funny side-effect used for testing RM_StreamIteratorDelete() is that if any
+ * entry has a field named "selfdestruct", the stream entry is deleted. It is
+ * however included in the results of this command.
+ */
+int stream_range(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleStreamID startid, endid;
+    if (RedisModule_StringToStreamID(argv[2], &startid) != REDISMODULE_OK ||
+        RedisModule_StringToStreamID(argv[3], &endid) != REDISMODULE_OK) {
+        RedisModule_ReplyWithError(ctx, "Invalid stream ID");
+        return REDISMODULE_OK;
+    }
+
+    /* If startid > endid, we swap and set the reverse flag. */
+    int flags = 0;
+    if (startid.ms > endid.ms ||
+        (startid.ms == endid.ms && startid.seq > endid.seq)) {
+        RedisModuleStreamID tmp = startid;
+        startid = endid;
+        endid = tmp;
+        flags |= REDISMODULE_STREAM_ITERATOR_REVERSE;
+    }
+
+    /* Open key and start iterator. */
+    int openflags = REDISMODULE_READ | REDISMODULE_WRITE;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], openflags);
+    if (RedisModule_StreamIteratorStart(key, flags,
+                                        &startid, &endid) != REDISMODULE_OK) {
+        /* Key is not a stream, etc. */
+        RedisModule_ReplyWithError(ctx, "ERR StreamIteratorStart failed");
+        RedisModule_CloseKey(key);
+        return REDISMODULE_OK;
+    }
+
+    /* Check error handling: Delete current entry when no current entry. */
+    assert(RedisModule_StreamIteratorDelete(key) ==
+           REDISMODULE_ERR);
+    assert(errno == ENOENT);
+
+    /* Check error handling: Fetch fields when no current entry. */
+    assert(RedisModule_StreamIteratorNextField(key, NULL, NULL) ==
+           REDISMODULE_ERR);
+    assert(errno == ENOENT);
+
+    /* Return array. */
+    RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
+    RedisModule_AutoMemory(ctx);
+    RedisModuleStreamID id;
+    long numfields;
+    long len = 0;
+    while (RedisModule_StreamIteratorNextID(key, &id,
+                                            &numfields) == REDISMODULE_OK) {
+        RedisModule_ReplyWithArray(ctx, 2);
+        RedisModuleString *id_str = RedisModule_CreateStringFromStreamID(ctx, &id);
+        RedisModule_ReplyWithString(ctx, id_str);
+        RedisModule_ReplyWithArray(ctx, numfields * 2);
+        int delete = 0;
+        RedisModuleString *field, *value;
+        for (long i = 0; i < numfields; i++) {
+            assert(RedisModule_StreamIteratorNextField(key, &field, &value) ==
+                   REDISMODULE_OK);
+            RedisModule_ReplyWithString(ctx, field);
+            RedisModule_ReplyWithString(ctx, value);
+            /* check if this is a "selfdestruct" field */
+            size_t field_len;
+            const char *field_str = RedisModule_StringPtrLen(field, &field_len);
+            if (!strncmp(field_str, "selfdestruct", field_len)) delete = 1;
+        }
+        if (delete) {
+            assert(RedisModule_StreamIteratorDelete(key) == REDISMODULE_OK);
+        }
+        /* check error handling: no more fields to fetch */
+        assert(RedisModule_StreamIteratorNextField(key, &field, &value) ==
+               REDISMODULE_ERR);
+        assert(errno == ENOENT);
+        len++;
+    }
+    RedisModule_ReplySetArrayLength(ctx, len);
+    RedisModule_StreamIteratorStop(key);
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+/*
+ * STREAM.TRIM key (MAXLEN (=|~) length | MINID (=|~) id)
+ */
+int stream_trim(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 5) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    /* Parse args */
+    int trim_by_id = 0; /* 0 = maxlen, 1 = minid */
+    long long maxlen;
+    RedisModuleStreamID minid;
+    size_t arg_len;
+    const char *arg = RedisModule_StringPtrLen(argv[2], &arg_len);
+    if (!strcasecmp(arg, "minid")) {
+        trim_by_id = 1;
+        if (RedisModule_StringToStreamID(argv[4], &minid) != REDISMODULE_OK) {
+            RedisModule_ReplyWithError(ctx, "ERR Invalid stream ID");
+            return REDISMODULE_OK;
+        }
+    } else if (!strcasecmp(arg, "maxlen")) {
+        if (RedisModule_StringToLongLong(argv[4], &maxlen) == REDISMODULE_ERR) {
+            RedisModule_ReplyWithError(ctx, "ERR Maxlen must be a number");
+            return REDISMODULE_OK;
+        }
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR Invalid arguments");
+        return REDISMODULE_OK;
+    }
+
+    /* Approx or exact */
+    int flags;
+    arg = RedisModule_StringPtrLen(argv[3], &arg_len);
+    if (arg_len == 1 && arg[0] == '~') {
+        flags = REDISMODULE_STREAM_TRIM_APPROX;
+    } else if (arg_len == 1 && arg[0] == '=') {
+        flags = 0;
+    } else {
+        RedisModule_ReplyWithError(ctx, "ERR Invalid approx-or-exact mark");
+        return REDISMODULE_OK;
+    }
+
+    /* Trim */
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    long long trimmed;
+    if (trim_by_id) {
+        trimmed = RedisModule_StreamTrimByID(key, flags, &minid);
+    } else {
+        trimmed = RedisModule_StreamTrimByLength(key, flags, maxlen);
+    }
+
+    /* Return result */
+    if (trimmed < 0) {
+        RedisModule_ReplyWithError(ctx, "ERR Trimming failed");
+    } else {
+        RedisModule_ReplyWithLongLong(ctx, trimmed);
+    }
+    RedisModule_CloseKey(key);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "stream", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "stream.add", stream_add, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "stream.addn", stream_addn, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "stream.delete", stream_delete, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "stream.range", stream_range, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx, "stream.trim", stream_trim, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/subcommands.c b/tests/modules/subcommands.c
new file mode 100644
index 0000000..1b2bc51
--- /dev/null
+++ b/tests/modules/subcommands.c
@@ -0,0 +1,112 @@
+#include "redismodule.h"
+
+#define UNUSED(V) ((void) V)
+
+int cmd_set(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int cmd_get(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+
+    if (argc > 4) /* For testing */
+        return RedisModule_WrongArity(ctx);
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+    return REDISMODULE_OK;
+}
+
+int cmd_get_fullname(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    UNUSED(argv);
+    UNUSED(argc);
+
+    const char *command_name = RedisModule_GetCurrentCommandName(ctx);
+    RedisModule_ReplyWithSimpleString(ctx, command_name);
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx, "subcommands", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Module command names cannot contain special characters. */
+    RedisModule_Assert(RedisModule_CreateCommand(ctx,"subcommands.char\r",NULL,"",0,0,0) == REDISMODULE_ERR);
+    RedisModule_Assert(RedisModule_CreateCommand(ctx,"subcommands.char\n",NULL,"",0,0,0) == REDISMODULE_ERR);
+    RedisModule_Assert(RedisModule_CreateCommand(ctx,"subcommands.char ",NULL,"",0,0,0) == REDISMODULE_ERR);
+
+    if (RedisModule_CreateCommand(ctx,"subcommands.bitarray",NULL,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    RedisModuleCommand *parent = RedisModule_GetCommand(ctx,"subcommands.bitarray");
+
+    if (RedisModule_CreateSubcommand(parent,"set",cmd_set,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Module subcommand names cannot contain special characters. */
+    RedisModule_Assert(RedisModule_CreateSubcommand(parent,"char|",cmd_set,"",0,0,0) == REDISMODULE_ERR);
+    RedisModule_Assert(RedisModule_CreateSubcommand(parent,"char@",cmd_set,"",0,0,0) == REDISMODULE_ERR);
+    RedisModule_Assert(RedisModule_CreateSubcommand(parent,"char=",cmd_set,"",0,0,0) == REDISMODULE_ERR);
+
+    RedisModuleCommand *subcmd = RedisModule_GetCommand(ctx,"subcommands.bitarray|set");
+    RedisModuleCommandInfo cmd_set_info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RW | REDISMODULE_CMD_KEY_UPDATE,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(subcmd, &cmd_set_info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateSubcommand(parent,"get",cmd_get,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    subcmd = RedisModule_GetCommand(ctx,"subcommands.bitarray|get");
+    RedisModuleCommandInfo cmd_get_info = {
+        .version = REDISMODULE_COMMAND_INFO_VERSION,
+        .key_specs = (RedisModuleCommandKeySpec[]){
+            {
+                .flags = REDISMODULE_CMD_KEY_RO | REDISMODULE_CMD_KEY_ACCESS,
+                .begin_search_type = REDISMODULE_KSPEC_BS_INDEX,
+                .bs.index.pos = 1,
+                .find_keys_type = REDISMODULE_KSPEC_FK_RANGE,
+                .fk.range = {0,1,0}
+            },
+            {0}
+        }
+    };
+    if (RedisModule_SetCommandInfo(subcmd, &cmd_get_info) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Get the name of the command currently running. */
+    if (RedisModule_CreateCommand(ctx,"subcommands.parent_get_fullname",cmd_get_fullname,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Get the name of the subcommand currently running. */
+    if (RedisModule_CreateCommand(ctx,"subcommands.sub",NULL,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModuleCommand *fullname_parent = RedisModule_GetCommand(ctx,"subcommands.sub");
+    if (RedisModule_CreateSubcommand(fullname_parent,"get_fullname",cmd_get_fullname,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    /* Sanity */
+
+    /* Trying to create the same subcommand fails */
+    RedisModule_Assert(RedisModule_CreateSubcommand(parent,"get",NULL,"",0,0,0) == REDISMODULE_ERR);
+
+    /* Trying to create a sub-subcommand fails */
+    RedisModule_Assert(RedisModule_CreateSubcommand(subcmd,"get",NULL,"",0,0,0) == REDISMODULE_ERR);
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/test_lazyfree.c b/tests/modules/test_lazyfree.c
new file mode 100644
index 0000000..7ba213f
--- /dev/null
+++ b/tests/modules/test_lazyfree.c
@@ -0,0 +1,196 @@
+/* This module emulates a linked list for lazyfree testing of modules, which
+ is a simplified version of 'hellotype.c'
+ */
+#include "redismodule.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <stdint.h>
+
+static RedisModuleType *LazyFreeLinkType;
+
+struct LazyFreeLinkNode {
+    int64_t value;
+    struct LazyFreeLinkNode *next;
+};
+
+struct LazyFreeLinkObject {
+    struct LazyFreeLinkNode *head;
+    size_t len; /* Number of elements added. */
+};
+
+struct LazyFreeLinkObject *createLazyFreeLinkObject(void) {
+    struct LazyFreeLinkObject *o;
+    o = RedisModule_Alloc(sizeof(*o));
+    o->head = NULL;
+    o->len = 0;
+    return o;
+}
+
+void LazyFreeLinkInsert(struct LazyFreeLinkObject *o, int64_t ele) {
+    struct LazyFreeLinkNode *next = o->head, *newnode, *prev = NULL;
+
+    while(next && next->value < ele) {
+        prev = next;
+        next = next->next;
+    }
+    newnode = RedisModule_Alloc(sizeof(*newnode));
+    newnode->value = ele;
+    newnode->next = next;
+    if (prev) {
+        prev->next = newnode;
+    } else {
+        o->head = newnode;
+    }
+    o->len++;
+}
+
+void LazyFreeLinkReleaseObject(struct LazyFreeLinkObject *o) {
+    struct LazyFreeLinkNode *cur, *next;
+    cur = o->head;
+    while(cur) {
+        next = cur->next;
+        RedisModule_Free(cur);
+        cur = next;
+    }
+    RedisModule_Free(o);
+}
+
+/* LAZYFREELINK.INSERT key value */
+int LazyFreeLinkInsert_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx); /* Use automatic memory management. */
+
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx,argv[1],
+        REDISMODULE_READ|REDISMODULE_WRITE);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY &&
+        RedisModule_ModuleTypeGetType(key) != LazyFreeLinkType)
+    {
+        return RedisModule_ReplyWithError(ctx,REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    long long value;
+    if ((RedisModule_StringToLongLong(argv[2],&value) != REDISMODULE_OK)) {
+        return RedisModule_ReplyWithError(ctx,"ERR invalid value: must be a signed 64 bit integer");
+    }
+
+    struct LazyFreeLinkObject *hto;
+    if (type == REDISMODULE_KEYTYPE_EMPTY) {
+        hto = createLazyFreeLinkObject();
+        RedisModule_ModuleTypeSetValue(key,LazyFreeLinkType,hto);
+    } else {
+        hto = RedisModule_ModuleTypeGetValue(key);
+    }
+
+    LazyFreeLinkInsert(hto,value);
+    RedisModule_SignalKeyAsReady(ctx,argv[1]);
+
+    RedisModule_ReplyWithLongLong(ctx,hto->len);
+    RedisModule_ReplicateVerbatim(ctx);
+    return REDISMODULE_OK;
+}
+
+/* LAZYFREELINK.LEN key */
+int LazyFreeLinkLen_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    RedisModule_AutoMemory(ctx); /* Use automatic memory management. */
+
+    if (argc != 2) return RedisModule_WrongArity(ctx);
+    RedisModuleKey *key = RedisModule_OpenKey(ctx,argv[1],
+                                              REDISMODULE_READ);
+    int type = RedisModule_KeyType(key);
+    if (type != REDISMODULE_KEYTYPE_EMPTY &&
+        RedisModule_ModuleTypeGetType(key) != LazyFreeLinkType)
+    {
+        return RedisModule_ReplyWithError(ctx,REDISMODULE_ERRORMSG_WRONGTYPE);
+    }
+
+    struct LazyFreeLinkObject *hto = RedisModule_ModuleTypeGetValue(key);
+    RedisModule_ReplyWithLongLong(ctx,hto ? hto->len : 0);
+    return REDISMODULE_OK;
+}
+
+void *LazyFreeLinkRdbLoad(RedisModuleIO *rdb, int encver) {
+    if (encver != 0) {
+        return NULL;
+    }
+    uint64_t elements = RedisModule_LoadUnsigned(rdb);
+    struct LazyFreeLinkObject *hto = createLazyFreeLinkObject();
+    while(elements--) {
+        int64_t ele = RedisModule_LoadSigned(rdb);
+        LazyFreeLinkInsert(hto,ele);
+    }
+    return hto;
+}
+
+void LazyFreeLinkRdbSave(RedisModuleIO *rdb, void *value) {
+    struct LazyFreeLinkObject *hto = value;
+    struct LazyFreeLinkNode *node = hto->head;
+    RedisModule_SaveUnsigned(rdb,hto->len);
+    while(node) {
+        RedisModule_SaveSigned(rdb,node->value);
+        node = node->next;
+    }
+}
+
+void LazyFreeLinkAofRewrite(RedisModuleIO *aof, RedisModuleString *key, void *value) {
+    struct LazyFreeLinkObject *hto = value;
+    struct LazyFreeLinkNode *node = hto->head;
+    while(node) {
+        RedisModule_EmitAOF(aof,"LAZYFREELINK.INSERT","sl",key,node->value);
+        node = node->next;
+    }
+}
+
+void LazyFreeLinkFree(void *value) {
+    LazyFreeLinkReleaseObject(value);
+}
+
+size_t LazyFreeLinkFreeEffort(RedisModuleString *key, const void *value) {
+    REDISMODULE_NOT_USED(key);
+    const struct LazyFreeLinkObject *hto = value;
+    return hto->len;
+}
+
+void LazyFreeLinkUnlink(RedisModuleString *key, const void *value) {
+    REDISMODULE_NOT_USED(key);
+    REDISMODULE_NOT_USED(value);
+    /* Here you can know which key and value is about to be freed. */
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"lazyfreetest",1,REDISMODULE_APIVER_1)
+        == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    /* We only allow our module to be loaded when the redis core version is greater than the version of my module */
+    if (RedisModule_GetTypeMethodVersion() < REDISMODULE_TYPE_METHOD_VERSION) {
+        return REDISMODULE_ERR;
+    }
+
+    RedisModuleTypeMethods tm = {
+        .version = REDISMODULE_TYPE_METHOD_VERSION,
+        .rdb_load = LazyFreeLinkRdbLoad,
+        .rdb_save = LazyFreeLinkRdbSave,
+        .aof_rewrite = LazyFreeLinkAofRewrite,
+        .free = LazyFreeLinkFree,
+        .free_effort = LazyFreeLinkFreeEffort,
+        .unlink = LazyFreeLinkUnlink,
+    };
+
+    LazyFreeLinkType = RedisModule_CreateDataType(ctx,"test_lazy",0,&tm);
+    if (LazyFreeLinkType == NULL) return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"lazyfreelink.insert",
+        LazyFreeLinkInsert_RedisCommand,"write deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"lazyfreelink.len",
+        LazyFreeLinkLen_RedisCommand,"readonly",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/testrdb.c b/tests/modules/testrdb.c
new file mode 100644
index 0000000..c31aebb
--- /dev/null
+++ b/tests/modules/testrdb.c
@@ -0,0 +1,405 @@
+#include "redismodule.h"
+
+#include <string.h>
+#include <assert.h>
+
+/* Module configuration, save aux or not? */
+#define CONF_AUX_OPTION_NO_AUX           0
+#define CONF_AUX_OPTION_SAVE2            1 << 0
+#define CONF_AUX_OPTION_BEFORE_KEYSPACE  1 << 1
+#define CONF_AUX_OPTION_AFTER_KEYSPACE   1 << 2
+#define CONF_AUX_OPTION_NO_DATA          1 << 3
+long long conf_aux_count = 0;
+
+/* Registered type */
+RedisModuleType *testrdb_type = NULL;
+
+/* Global values to store and persist to aux */
+RedisModuleString *before_str = NULL;
+RedisModuleString *after_str = NULL;
+
+/* Global values used to keep aux from db being loaded (in case of async_loading) */
+RedisModuleString *before_str_temp = NULL;
+RedisModuleString *after_str_temp = NULL;
+
+/* Indicates whether there is an async replication in progress.
+ * We control this value from RedisModuleEvent_ReplAsyncLoad events. */
+int async_loading = 0;
+
+int n_aux_load_called = 0;
+
+void replAsyncLoadCallback(RedisModuleCtx *ctx, RedisModuleEvent e, uint64_t sub, void *data)
+{
+    REDISMODULE_NOT_USED(e);
+    REDISMODULE_NOT_USED(data);
+
+    switch (sub) {
+    case REDISMODULE_SUBEVENT_REPL_ASYNC_LOAD_STARTED:
+        assert(async_loading == 0);
+        async_loading = 1;
+        break;
+    case REDISMODULE_SUBEVENT_REPL_ASYNC_LOAD_ABORTED:
+        /* Discard temp aux */
+        if (before_str_temp)
+            RedisModule_FreeString(ctx, before_str_temp);
+        if (after_str_temp)
+            RedisModule_FreeString(ctx, after_str_temp);
+        before_str_temp = NULL;
+        after_str_temp = NULL;
+
+        async_loading = 0;
+        break;
+    case REDISMODULE_SUBEVENT_REPL_ASYNC_LOAD_COMPLETED:
+        if (before_str)
+            RedisModule_FreeString(ctx, before_str);
+        if (after_str)
+            RedisModule_FreeString(ctx, after_str);
+        before_str = before_str_temp;
+        after_str = after_str_temp;
+
+        before_str_temp = NULL;
+        after_str_temp = NULL;
+
+        async_loading = 0;
+        break;
+    default:
+        assert(0);
+    }
+}
+
+void *testrdb_type_load(RedisModuleIO *rdb, int encver) {
+    int count = RedisModule_LoadSigned(rdb);
+    RedisModuleString *str = RedisModule_LoadString(rdb);
+    float f = RedisModule_LoadFloat(rdb);
+    long double ld = RedisModule_LoadLongDouble(rdb);
+    if (RedisModule_IsIOError(rdb)) {
+        RedisModuleCtx *ctx = RedisModule_GetContextFromIO(rdb);
+        if (str)
+            RedisModule_FreeString(ctx, str);
+        return NULL;
+    }
+    /* Using the values only after checking for io errors. */
+    assert(count==1);
+    assert(encver==1);
+    assert(f==1.5f);
+    assert(ld==0.333333333333333333L);
+    return str;
+}
+
+void testrdb_type_save(RedisModuleIO *rdb, void *value) {
+    RedisModuleString *str = (RedisModuleString*)value;
+    RedisModule_SaveSigned(rdb, 1);
+    RedisModule_SaveString(rdb, str);
+    RedisModule_SaveFloat(rdb, 1.5);
+    RedisModule_SaveLongDouble(rdb, 0.333333333333333333L);
+}
+
+void testrdb_aux_save(RedisModuleIO *rdb, int when) {
+    if (!(conf_aux_count & CONF_AUX_OPTION_BEFORE_KEYSPACE)) assert(when == REDISMODULE_AUX_AFTER_RDB);
+    if (!(conf_aux_count & CONF_AUX_OPTION_AFTER_KEYSPACE)) assert(when == REDISMODULE_AUX_BEFORE_RDB);
+    assert(conf_aux_count!=CONF_AUX_OPTION_NO_AUX);
+    if (when == REDISMODULE_AUX_BEFORE_RDB) {
+        if (before_str) {
+            RedisModule_SaveSigned(rdb, 1);
+            RedisModule_SaveString(rdb, before_str);
+        } else {
+            RedisModule_SaveSigned(rdb, 0);
+        }
+    } else {
+        if (after_str) {
+            RedisModule_SaveSigned(rdb, 1);
+            RedisModule_SaveString(rdb, after_str);
+        } else {
+            RedisModule_SaveSigned(rdb, 0);
+        }
+    }
+}
+
+int testrdb_aux_load(RedisModuleIO *rdb, int encver, int when) {
+    assert(encver == 1);
+    if (!(conf_aux_count & CONF_AUX_OPTION_BEFORE_KEYSPACE)) assert(when == REDISMODULE_AUX_AFTER_RDB);
+    if (!(conf_aux_count & CONF_AUX_OPTION_AFTER_KEYSPACE)) assert(when == REDISMODULE_AUX_BEFORE_RDB);
+    assert(conf_aux_count!=CONF_AUX_OPTION_NO_AUX);
+    RedisModuleCtx *ctx = RedisModule_GetContextFromIO(rdb);
+    if (when == REDISMODULE_AUX_BEFORE_RDB) {
+        if (async_loading == 0) {
+            if (before_str)
+                RedisModule_FreeString(ctx, before_str);
+            before_str = NULL;
+            int count = RedisModule_LoadSigned(rdb);
+            if (RedisModule_IsIOError(rdb))
+                return REDISMODULE_ERR;
+            if (count)
+                before_str = RedisModule_LoadString(rdb);
+        } else {
+            if (before_str_temp)
+                RedisModule_FreeString(ctx, before_str_temp);
+            before_str_temp = NULL;
+            int count = RedisModule_LoadSigned(rdb);
+            if (RedisModule_IsIOError(rdb))
+                return REDISMODULE_ERR;
+            if (count)
+                before_str_temp = RedisModule_LoadString(rdb);
+        }
+    } else {
+        if (async_loading == 0) {
+            if (after_str)
+                RedisModule_FreeString(ctx, after_str);
+            after_str = NULL;
+            int count = RedisModule_LoadSigned(rdb);
+            if (RedisModule_IsIOError(rdb))
+                return REDISMODULE_ERR;
+            if (count)
+                after_str = RedisModule_LoadString(rdb);
+        } else {
+            if (after_str_temp)
+                RedisModule_FreeString(ctx, after_str_temp);
+            after_str_temp = NULL;
+            int count = RedisModule_LoadSigned(rdb);
+            if (RedisModule_IsIOError(rdb))
+                return REDISMODULE_ERR;
+            if (count)
+                after_str_temp = RedisModule_LoadString(rdb);
+        }
+    }
+
+    if (RedisModule_IsIOError(rdb))
+        return REDISMODULE_ERR;
+    return REDISMODULE_OK;
+}
+
+void testrdb_type_free(void *value) {
+    if (value)
+        RedisModule_FreeString(NULL, (RedisModuleString*)value);
+}
+
+int testrdb_set_before(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    if (before_str)
+        RedisModule_FreeString(ctx, before_str);
+    before_str = argv[1];
+    RedisModule_RetainString(ctx, argv[1]);
+    RedisModule_ReplyWithLongLong(ctx, 1);
+    return REDISMODULE_OK;
+}
+
+int testrdb_get_before(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    if (before_str)
+        RedisModule_ReplyWithString(ctx, before_str);
+    else
+        RedisModule_ReplyWithStringBuffer(ctx, "", 0);
+    return REDISMODULE_OK;
+}
+
+/* For purpose of testing module events, expose variable state during async_loading. */
+int testrdb_async_loading_get_before(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    if (before_str_temp)
+        RedisModule_ReplyWithString(ctx, before_str_temp);
+    else
+        RedisModule_ReplyWithStringBuffer(ctx, "", 0);
+    return REDISMODULE_OK;
+}
+
+int testrdb_set_after(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    if (after_str)
+        RedisModule_FreeString(ctx, after_str);
+    after_str = argv[1];
+    RedisModule_RetainString(ctx, argv[1]);
+    RedisModule_ReplyWithLongLong(ctx, 1);
+    return REDISMODULE_OK;
+}
+
+int testrdb_get_after(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(argv);
+    if (argc != 1){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+    if (after_str)
+        RedisModule_ReplyWithString(ctx, after_str);
+    else
+        RedisModule_ReplyWithStringBuffer(ctx, "", 0);
+    return REDISMODULE_OK;
+}
+
+int testrdb_set_key(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 3){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
+    RedisModuleString *str = RedisModule_ModuleTypeGetValue(key);
+    if (str)
+        RedisModule_FreeString(ctx, str);
+    RedisModule_ModuleTypeSetValue(key, testrdb_type, argv[2]);
+    RedisModule_RetainString(ctx, argv[2]);
+    RedisModule_CloseKey(key);
+    RedisModule_ReplyWithLongLong(ctx, 1);
+    return REDISMODULE_OK;
+}
+
+int testrdb_get_key(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2){
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_READ);
+    RedisModuleString *str = RedisModule_ModuleTypeGetValue(key);
+    RedisModule_CloseKey(key);
+    RedisModule_ReplyWithString(ctx, str);
+    return REDISMODULE_OK;
+}
+
+int testrdb_get_n_aux_load_called(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    REDISMODULE_NOT_USED(ctx);
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    RedisModule_ReplyWithLongLong(ctx, n_aux_load_called);
+    return REDISMODULE_OK;
+}
+
+int test2rdb_aux_load(RedisModuleIO *rdb, int encver, int when) {
+    REDISMODULE_NOT_USED(rdb);
+    REDISMODULE_NOT_USED(encver);
+    REDISMODULE_NOT_USED(when);
+    n_aux_load_called++;
+    return REDISMODULE_OK;
+}
+
+void test2rdb_aux_save(RedisModuleIO *rdb, int when) {
+    REDISMODULE_NOT_USED(rdb);
+    REDISMODULE_NOT_USED(when);
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"testrdb",1,REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    RedisModule_SetModuleOptions(ctx, REDISMODULE_OPTIONS_HANDLE_IO_ERRORS | REDISMODULE_OPTIONS_HANDLE_REPL_ASYNC_LOAD);
+
+    if (argc > 0)
+        RedisModule_StringToLongLong(argv[0], &conf_aux_count);
+
+    if (conf_aux_count==CONF_AUX_OPTION_NO_AUX) {
+        RedisModuleTypeMethods datatype_methods = {
+            .version = 1,
+            .rdb_load = testrdb_type_load,
+            .rdb_save = testrdb_type_save,
+            .aof_rewrite = NULL,
+            .digest = NULL,
+            .free = testrdb_type_free,
+        };
+
+        testrdb_type = RedisModule_CreateDataType(ctx, "test__rdb", 1, &datatype_methods);
+        if (testrdb_type == NULL)
+            return REDISMODULE_ERR;
+    } else if (!(conf_aux_count & CONF_AUX_OPTION_NO_DATA)) {
+        RedisModuleTypeMethods datatype_methods = {
+            .version = REDISMODULE_TYPE_METHOD_VERSION,
+            .rdb_load = testrdb_type_load,
+            .rdb_save = testrdb_type_save,
+            .aof_rewrite = NULL,
+            .digest = NULL,
+            .free = testrdb_type_free,
+            .aux_load = testrdb_aux_load,
+            .aux_save = testrdb_aux_save,
+            .aux_save_triggers = ((conf_aux_count & CONF_AUX_OPTION_BEFORE_KEYSPACE) ? REDISMODULE_AUX_BEFORE_RDB : 0) |
+                                 ((conf_aux_count & CONF_AUX_OPTION_AFTER_KEYSPACE)  ? REDISMODULE_AUX_AFTER_RDB : 0)
+        };
+
+        if (conf_aux_count & CONF_AUX_OPTION_SAVE2) {
+            datatype_methods.aux_save2 = testrdb_aux_save;
+        }
+
+        testrdb_type = RedisModule_CreateDataType(ctx, "test__rdb", 1, &datatype_methods);
+        if (testrdb_type == NULL)
+            return REDISMODULE_ERR;
+    } else {
+
+        /* Used to verify that aux_save2 api without any data, saves nothing to the RDB. */
+        RedisModuleTypeMethods datatype_methods = {
+            .version = REDISMODULE_TYPE_METHOD_VERSION,
+            .aux_load = test2rdb_aux_load,
+            .aux_save = test2rdb_aux_save,
+            .aux_save_triggers = ((conf_aux_count & CONF_AUX_OPTION_BEFORE_KEYSPACE) ? REDISMODULE_AUX_BEFORE_RDB : 0) |
+                                 ((conf_aux_count & CONF_AUX_OPTION_AFTER_KEYSPACE)  ? REDISMODULE_AUX_AFTER_RDB : 0)
+        };
+        if (conf_aux_count & CONF_AUX_OPTION_SAVE2) {
+            datatype_methods.aux_save2 = test2rdb_aux_save;
+        }
+
+        RedisModule_CreateDataType(ctx, "test__rdb", 1, &datatype_methods);
+    }
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.set.before", testrdb_set_before,"deny-oom",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.get.before", testrdb_get_before,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.async_loading.get.before", testrdb_async_loading_get_before,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.set.after", testrdb_set_after,"deny-oom",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.get.after", testrdb_get_after,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.set.key", testrdb_set_key,"deny-oom",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.get.key", testrdb_get_key,"",1,1,1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"testrdb.get.n_aux_load_called", testrdb_get_n_aux_load_called,"",1,1,1) == REDISMODULE_ERR)
+            return REDISMODULE_ERR;
+
+    RedisModule_SubscribeToServerEvent(ctx,
+        RedisModuleEvent_ReplAsyncLoad, replAsyncLoadCallback);
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnUnload(RedisModuleCtx *ctx) {
+    if (before_str)
+        RedisModule_FreeString(ctx, before_str);
+    if (after_str)
+        RedisModule_FreeString(ctx, after_str);
+    if (before_str_temp)
+        RedisModule_FreeString(ctx, before_str_temp);
+    if (after_str_temp)
+        RedisModule_FreeString(ctx, after_str_temp);
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/timer.c b/tests/modules/timer.c
new file mode 100644
index 0000000..c9bd636
--- /dev/null
+++ b/tests/modules/timer.c
@@ -0,0 +1,102 @@
+
+#include "redismodule.h"
+
+static void timer_callback(RedisModuleCtx *ctx, void *data)
+{
+    RedisModuleString *keyname = data;
+    RedisModuleCallReply *reply;
+
+    reply = RedisModule_Call(ctx, "INCR", "s", keyname);
+    if (reply != NULL)
+        RedisModule_FreeCallReply(reply);
+    RedisModule_FreeString(ctx, keyname);
+}
+
+int test_createtimer(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 3) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long period;
+    if (RedisModule_StringToLongLong(argv[1], &period) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx, "Invalid time specified.");
+        return REDISMODULE_OK;
+    }
+
+    RedisModuleString *keyname = argv[2];
+    RedisModule_RetainString(ctx, keyname);
+
+    RedisModuleTimerID id = RedisModule_CreateTimer(ctx, period, timer_callback, keyname);
+    RedisModule_ReplyWithLongLong(ctx, id);
+
+    return REDISMODULE_OK;
+}
+
+int test_gettimer(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long id;
+    if (RedisModule_StringToLongLong(argv[1], &id) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx, "Invalid id specified.");
+        return REDISMODULE_OK;
+    }
+
+    uint64_t remaining;
+    RedisModuleString *keyname;
+    if (RedisModule_GetTimerInfo(ctx, id, &remaining, (void **)&keyname) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithNull(ctx);
+    } else {
+        RedisModule_ReplyWithArray(ctx, 2);
+        RedisModule_ReplyWithString(ctx, keyname);
+        RedisModule_ReplyWithLongLong(ctx, remaining);
+    }
+
+    return REDISMODULE_OK;
+}
+
+int test_stoptimer(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    if (argc != 2) {
+        RedisModule_WrongArity(ctx);
+        return REDISMODULE_OK;
+    }
+
+    long long id;
+    if (RedisModule_StringToLongLong(argv[1], &id) == REDISMODULE_ERR) {
+        RedisModule_ReplyWithError(ctx, "Invalid id specified.");
+        return REDISMODULE_OK;
+    }
+
+    int ret = 0;
+    RedisModuleString *keyname;
+    if (RedisModule_StopTimer(ctx, id, (void **) &keyname) == REDISMODULE_OK) {
+        RedisModule_FreeString(ctx, keyname);
+        ret = 1;
+    }
+
+    RedisModule_ReplyWithLongLong(ctx, ret);
+    return REDISMODULE_OK;
+}
+
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"timer",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"test.createtimer", test_createtimer,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.gettimer", test_gettimer,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+    if (RedisModule_CreateCommand(ctx,"test.stoptimer", test_stoptimer,"",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/usercall.c b/tests/modules/usercall.c
new file mode 100644
index 0000000..6b23974
--- /dev/null
+++ b/tests/modules/usercall.c
@@ -0,0 +1,228 @@
+#include "redismodule.h"
+#include <pthread.h>
+#include <assert.h>
+
+#define UNUSED(V) ((void) V)
+
+RedisModuleUser *user = NULL;
+
+int call_without_user(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 2) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    const char *cmd = RedisModule_StringPtrLen(argv[1], NULL);
+
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, cmd, "Ev", argv + 2, argc - 2);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    return REDISMODULE_OK;
+}
+
+int call_with_user_flag(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc < 3) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    RedisModule_SetContextUser(ctx, user);
+
+    /* Append Ev to the provided flags. */
+    RedisModuleString *flags = RedisModule_CreateStringFromString(ctx, argv[1]);
+    RedisModule_StringAppendBuffer(ctx, flags, "Ev", 2);
+
+    const char* flg = RedisModule_StringPtrLen(flags, NULL);
+    const char* cmd = RedisModule_StringPtrLen(argv[2], NULL);
+
+    RedisModuleCallReply* rep = RedisModule_Call(ctx, cmd, flg, argv + 3, argc - 3);
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+    RedisModule_FreeString(ctx, flags);
+
+    return REDISMODULE_OK;
+}
+
+int add_to_acl(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 2) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    size_t acl_len;
+    const char *acl = RedisModule_StringPtrLen(argv[1], &acl_len);
+
+    RedisModuleString *error;
+    int ret = RedisModule_SetModuleUserACLString(ctx, user, acl, &error);
+    if (ret) {
+        size_t len;
+        const char * e = RedisModule_StringPtrLen(error, &len);
+        RedisModule_ReplyWithError(ctx, e);
+        return REDISMODULE_OK;
+    }
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+    return REDISMODULE_OK;
+}
+
+int get_acl(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+
+    if (argc != 1) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    RedisModule_Assert(user != NULL);
+
+    RedisModuleString *acl = RedisModule_GetModuleUserACLString(user);
+
+    RedisModule_ReplyWithString(ctx, acl);
+
+    RedisModule_FreeString(NULL, acl);
+
+    return REDISMODULE_OK;
+}
+
+int reset_user(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+
+    if (argc != 1) {
+        return RedisModule_WrongArity(ctx);
+    }
+
+    if (user != NULL) {
+        RedisModule_FreeModuleUser(user);
+    }
+
+    user = RedisModule_CreateModuleUser("module_user");
+
+    RedisModule_ReplyWithSimpleString(ctx, "OK");
+
+    return REDISMODULE_OK;
+}
+
+typedef struct {
+    RedisModuleString **argv;
+    int argc;
+    RedisModuleBlockedClient *bc;
+} bg_call_data;
+
+void *bg_call_worker(void *arg) {
+    bg_call_data *bg = arg;
+
+    // Get Redis module context
+    RedisModuleCtx *ctx = RedisModule_GetThreadSafeContext(bg->bc);
+
+    // Acquire GIL
+    RedisModule_ThreadSafeContextLock(ctx);
+
+    // Set user
+    RedisModule_SetContextUser(ctx, user);
+
+    // Call the command
+    size_t format_len;
+    RedisModuleString *format_redis_str = RedisModule_CreateString(NULL, "v", 1);
+    const char *format = RedisModule_StringPtrLen(bg->argv[1], &format_len);
+    RedisModule_StringAppendBuffer(NULL, format_redis_str, format, format_len);
+    RedisModule_StringAppendBuffer(NULL, format_redis_str, "E", 1);
+    format = RedisModule_StringPtrLen(format_redis_str, NULL);
+    const char *cmd = RedisModule_StringPtrLen(bg->argv[2], NULL);
+    RedisModuleCallReply *rep = RedisModule_Call(ctx, cmd, format, bg->argv + 3, bg->argc - 3);
+    RedisModule_FreeString(NULL, format_redis_str);
+
+    // Release GIL
+    RedisModule_ThreadSafeContextUnlock(ctx);
+
+    // Reply to client
+    if (!rep) {
+        RedisModule_ReplyWithError(ctx, "NULL reply returned");
+    } else {
+        RedisModule_ReplyWithCallReply(ctx, rep);
+        RedisModule_FreeCallReply(rep);
+    }
+
+    // Unblock client
+    RedisModule_UnblockClient(bg->bc, NULL);
+
+    /* Free the arguments */
+    for (int i=0; i<bg->argc; i++)
+        RedisModule_FreeString(ctx, bg->argv[i]);
+    RedisModule_Free(bg->argv);
+    RedisModule_Free(bg);
+
+    // Free the Redis module context
+    RedisModule_FreeThreadSafeContext(ctx);
+
+    return NULL;
+}
+
+int call_with_user_bg(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
+{
+    UNUSED(argv);
+    UNUSED(argc);
+
+    /* Make sure we're not trying to block a client when we shouldn't */
+    int flags = RedisModule_GetContextFlags(ctx);
+    int allFlags = RedisModule_GetContextFlagsAll();
+    if ((allFlags & REDISMODULE_CTX_FLAGS_MULTI) &&
+        (flags & REDISMODULE_CTX_FLAGS_MULTI)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not supported inside multi");
+        return REDISMODULE_OK;
+    }
+    if ((allFlags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING) &&
+        (flags & REDISMODULE_CTX_FLAGS_DENY_BLOCKING)) {
+        RedisModule_ReplyWithSimpleString(ctx, "Blocked client is not allowed");
+        return REDISMODULE_OK;
+    }
+
+    /* Make a copy of the arguments and pass them to the thread. */
+    bg_call_data *bg = RedisModule_Alloc(sizeof(bg_call_data));
+    bg->argv = RedisModule_Alloc(sizeof(RedisModuleString*)*argc);
+    bg->argc = argc;
+    for (int i=0; i<argc; i++)
+        bg->argv[i] = RedisModule_HoldString(ctx, argv[i]);
+
+    /* Block the client */
+    bg->bc = RedisModule_BlockClient(ctx, NULL, NULL, NULL, 0);
+
+    /* Start a thread to handle the request */
+    pthread_t tid;
+    int res = pthread_create(&tid, NULL, bg_call_worker, bg);
+    assert(res == 0);
+
+    return REDISMODULE_OK;
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+
+    if (RedisModule_Init(ctx,"usercall",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"usercall.call_without_user", call_without_user,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"usercall.call_with_user_flag", call_with_user_flag,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "usercall.call_with_user_bg", call_with_user_bg, "write", 0, 0, 0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "usercall.add_to_acl", add_to_acl, "write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"usercall.reset_user", reset_user,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx,"usercall.get_acl", get_acl,"write",0,0,0) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/modules/zset.c b/tests/modules/zset.c
new file mode 100644
index 0000000..13f2ab3
--- /dev/null
+++ b/tests/modules/zset.c
@@ -0,0 +1,91 @@
+#include "redismodule.h"
+#include <math.h>
+#include <errno.h>
+
+/* ZSET.REM key element
+ *
+ * Removes an occurrence of an element from a sorted set. Replies with the
+ * number of removed elements (0 or 1).
+ */
+int zset_rem(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 3) return RedisModule_WrongArity(ctx);
+    RedisModule_AutoMemory(ctx);
+    int keymode = REDISMODULE_READ | REDISMODULE_WRITE;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], keymode);
+    int deleted;
+    if (RedisModule_ZsetRem(key, argv[2], &deleted) == REDISMODULE_OK)
+        return RedisModule_ReplyWithLongLong(ctx, deleted);
+    else
+        return RedisModule_ReplyWithError(ctx, "ERR ZsetRem failed");
+}
+
+/* ZSET.ADD key score member
+ *
+ * Adds a specified member with the specified score to the sorted
+ * set stored at key.
+ */
+int zset_add(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) return RedisModule_WrongArity(ctx);
+    RedisModule_AutoMemory(ctx);
+    int keymode = REDISMODULE_READ | REDISMODULE_WRITE;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], keymode);
+
+    size_t len;
+    double score;
+    char *endptr;
+    const char *str = RedisModule_StringPtrLen(argv[2], &len);
+    score = strtod(str, &endptr);
+    if (*endptr != '\0' || errno == ERANGE)
+        return RedisModule_ReplyWithError(ctx, "value is not a valid float");
+
+    if (RedisModule_ZsetAdd(key, score, argv[3], NULL) == REDISMODULE_OK)
+        return RedisModule_ReplyWithSimpleString(ctx, "OK");
+    else
+        return RedisModule_ReplyWithError(ctx, "ERR ZsetAdd failed");
+}
+
+/* ZSET.INCRBY key member increment
+ *
+ * Increments the score stored at member in the sorted set stored at key by increment.
+ * Replies with the new score of this element.
+ */
+int zset_incrby(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    if (argc != 4) return RedisModule_WrongArity(ctx);
+    RedisModule_AutoMemory(ctx);
+    int keymode = REDISMODULE_READ | REDISMODULE_WRITE;
+    RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], keymode);
+
+    size_t len;
+    double score, newscore;
+    char *endptr;
+    const char *str = RedisModule_StringPtrLen(argv[3], &len);
+    score = strtod(str, &endptr);
+    if (*endptr != '\0' || errno == ERANGE)
+        return RedisModule_ReplyWithError(ctx, "value is not a valid float");
+
+    if (RedisModule_ZsetIncrby(key, score, argv[2], NULL, &newscore) == REDISMODULE_OK)
+        return RedisModule_ReplyWithDouble(ctx, newscore);
+    else
+        return RedisModule_ReplyWithError(ctx, "ERR ZsetIncrby failed");
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx, "zset", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "zset.rem", zset_rem, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "zset.add", zset_add, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    if (RedisModule_CreateCommand(ctx, "zset.incrby", zset_incrby, "write",
+                                  1, 1, 1) == REDISMODULE_ERR)
+        return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}