diff --git a/integration-tests-ex/cases/cluster.sh b/integration-tests-ex/cases/cluster.sh
index f7c6cb92f0bf..dfe1037b43ca 100755
--- a/integration-tests-ex/cases/cluster.sh
+++ b/integration-tests-ex/cases/cluster.sh
@@ -27,15 +27,17 @@ set -e
 # Enable for debugging
 #set -x
 
-export MODULE_DIR=$(cd $(dirname $0) && pwd)
+export BASE_MODULE_DIR=$(cd $(dirname $0) && pwd)
+
+# The location of the tests, which may be different than
+# the location of this file.
+export MODULE_DIR=${IT_MODULE_DIR:-$BASE_MODULE_DIR}
 
 function usage {
   cat <<EOF
 Usage: $0 cmd [category]
   -h, help
       Display this message
-  prepare category
-      Generate the docker-compose.yaml file for the category for debugging.
   up category
       Start the cluster
   down category
@@ -45,7 +47,7 @@ Usage: $0 cmd [category]
   compose-cmd category
       Pass the command to Docker compose. Cluster should already be up.
   gen category
-      Generate docker-compose.yaml files (only.) Done automatically as
+      Generate docker-compose.yaml file (only.) Done automatically as
       part of up. Use only for debugging.
 EOF
 }
@@ -60,7 +62,7 @@ CMD=$1
 shift
 
 function check_env_file {
-  export ENV_FILE=$MODULE_DIR/../image/target/env.sh
+  export ENV_FILE=$BASE_MODULE_DIR/../image/target/env.sh
   if [ ! -f $ENV_FILE ]; then
     echo "Please build the Docker test image before testing" 1>&2
     exit 1
@@ -127,33 +129,33 @@ function show_status {
 function build_shared_dir {
   mkdir -p $SHARED_DIR
   # Must start with an empty DB to keep MySQL happy
-  rm -rf $SHARED_DIR/db
+  sudo rm -rf $SHARED_DIR/db
   mkdir -p $SHARED_DIR/logs
   mkdir -p $SHARED_DIR/tasklogs
   mkdir -p $SHARED_DIR/db
   mkdir -p $SHARED_DIR/kafka
   mkdir -p $SHARED_DIR/resources
-  cp $MODULE_DIR/assets/log4j2.xml $SHARED_DIR/resources
+  cp $BASE_MODULE_DIR/assets/log4j2.xml $SHARED_DIR/resources
   # Permissions in some build setups are screwed up. See above. The user
   # which runs Docker does not have permission to write into the /shared
   # directory. Force ownership to allow writing.
-  chmod -R a+rwx $SHARED_DIR
+  sudo chmod -R a+rwx $SHARED_DIR
 }
 
 # Either generate the docker-compose file, or use "static" versions.
 function docker_file {
 
-  # If a template exists, generate the docker-compose.yaml file. Copy over the Common
-  # folder.
-  TEMPLATE_DIR=$MODULE_DIR/templates
-  TEMPLATE_SCRIPT=${DRUID_INTEGRATION_TEST_GROUP}.py
-  if [ -f "$TEMPLATE_DIR/$TEMPLATE_SCRIPT" ]; then
+  # If a template exists, generate the docker-compose.yaml file.
+  # Copy over the Common folder.
+  TEMPLATE_SCRIPT=docker-compose.py
+  if [ -f "$CLUSTER_DIR/$TEMPLATE_SCRIPT" ]; then
+    export PYTHONPATH=$BASE_MODULE_DIR/cluster
     export COMPOSE_DIR=$TARGET_DIR/cluster/$DRUID_INTEGRATION_TEST_GROUP
     mkdir -p $COMPOSE_DIR
-    pushd $TEMPLATE_DIR > /dev/null
+    pushd $CLUSTER_DIR > /dev/null
     python3 $TEMPLATE_SCRIPT
     popd > /dev/null
-    cp -r $MODULE_DIR/cluster/Common $TARGET_DIR/cluster
+    cp -r $BASE_MODULE_DIR/cluster/Common $TARGET_DIR/cluster
   else
     # Else, use the existing non-template file in place.
     if [ ! -d $CLUSTER_DIR ]; then
@@ -205,6 +207,13 @@ function verify_docker_file {
   fi
 }
 
+function run_setup {
+  SETUP_SCRIPT="$CLUSTER_DIR/setup.sh"
+  if [ -f "$SETUP_SCRIPT" ]; then
+    source "$SETUP_SCRIPT"
+  fi
+}
+
 # Determine if docker-compose is available. If not, assume Docker supports
 # the compose subcommand
 set +e
@@ -219,17 +228,6 @@ set -e
 # Print environment for debugging
 #env
 
-# Determine if docker-compose is available. If not, assume Docker supports
-# the compose subcommand
-set +e
-if which docker-compose > /dev/null
-then
-  DOCKER_COMPOSE='docker-compose'
-else
-  DOCKER_COMPOSE='docker compose'
-fi
-set -e
-
 case $CMD in
   "-h" )
     usage
@@ -238,17 +236,11 @@ case $CMD in
     usage
     $DOCKER_COMPOSE help
     ;;
-  "prepare" )
-    check_env_file
-    category $*
-    build_shared_dir
-    docker_file
-    ;;
   "gen" )
     category $*
     build_shared_dir
     docker_file
-    echo "Generated file is in $COMPOSE_DIR"
+    echo "Generated file is $COMPOSE_DIR/docker-compose.yaml"
     ;;
   "up" )
     check_env_file
@@ -256,6 +248,7 @@ case $CMD in
     echo "Starting cluster $DRUID_INTEGRATION_TEST_GROUP"
     build_shared_dir
     docker_file
+    run_setup
     cd $COMPOSE_DIR
     $DOCKER_COMPOSE $DOCKER_ARGS up -d
     # Enable the following for debugging
diff --git a/integration-tests-ex/cases/templates/AzureDeepStorage.py b/integration-tests-ex/cases/cluster/AzureDeepStorage/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/AzureDeepStorage.py
rename to integration-tests-ex/cases/cluster/AzureDeepStorage/docker-compose.py
diff --git a/integration-tests-ex/cases/cluster/AzureDeepStorage/verify.sh b/integration-tests-ex/cases/cluster/AzureDeepStorage/verify.sh
new file mode 100644
index 000000000000..f12a2901479f
--- /dev/null
+++ b/integration-tests-ex/cases/cluster/AzureDeepStorage/verify.sh
@@ -0,0 +1,19 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#--------------------------------------------------------------------
+
+require_env_var AZURE_ACCOUNT
+require_env_var AZURE_KEY
+require_env_var AZURE_CONTAINER
diff --git a/integration-tests-ex/cases/templates/BatchIndex.py b/integration-tests-ex/cases/cluster/BatchIndex/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/BatchIndex.py
rename to integration-tests-ex/cases/cluster/BatchIndex/docker-compose.py
diff --git a/integration-tests-ex/cases/cluster/Common/dependencies.yaml b/integration-tests-ex/cases/cluster/Common/dependencies.yaml
index 1f43dc5a751a..a4a37c7c979d 100644
--- a/integration-tests-ex/cases/cluster/Common/dependencies.yaml
+++ b/integration-tests-ex/cases/cluster/Common/dependencies.yaml
@@ -71,6 +71,7 @@ services:
     # platform: linux/x86_64
     image: mysql:$MYSQL_IMAGE_VERSION
     container_name: metadata
+    restart: always
     command:
       - --character-set-server=utf8mb4
     networks:
@@ -79,7 +80,7 @@ services:
     ports:
       - 3306:3306
     volumes:
-      - ${SHARED_DIR}/db:/var/lib/mysql
+      - ${SHARED_DIR}/db/init.sql:/docker-entrypoint-initdb.d/init.sql
     environment:
       MYSQL_ROOT_PASSWORD: driud
       MYSQL_DATABASE: druid
diff --git a/integration-tests-ex/cases/templates/GcsDeepStorage.py b/integration-tests-ex/cases/cluster/GcsDeepStorage/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/GcsDeepStorage.py
rename to integration-tests-ex/cases/cluster/GcsDeepStorage/docker-compose.py
diff --git a/integration-tests-ex/cases/cluster/GcsDeepStorage/verify.sh b/integration-tests-ex/cases/cluster/GcsDeepStorage/verify.sh
new file mode 100644
index 000000000000..a1e30ceba568
--- /dev/null
+++ b/integration-tests-ex/cases/cluster/GcsDeepStorage/verify.sh
@@ -0,0 +1,23 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#--------------------------------------------------------------------
+
+require_env_var GOOGLE_BUCKET
+require_env_var GOOGLE_PREFIX
+require_env_var GOOGLE_APPLICATION_CREDENTIALS
+if [ ! -f "$GOOGLE_APPLICATION_CREDENTIALS" ]; then
+  echo "Required file GOOGLE_APPLICATION_CREDENTIALS=$GOOGLE_APPLICATION_CREDENTIALS is missing" 1>&2
+  exit 1
+fi
diff --git a/integration-tests-ex/cases/templates/HighAvailability.py b/integration-tests-ex/cases/cluster/HighAvailability/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/HighAvailability.py
rename to integration-tests-ex/cases/cluster/HighAvailability/docker-compose.py
diff --git a/integration-tests-ex/cases/templates/MultiStageQuery.py b/integration-tests-ex/cases/cluster/MultiStageQuery/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/MultiStageQuery.py
rename to integration-tests-ex/cases/cluster/MultiStageQuery/docker-compose.py
diff --git a/integration-tests-ex/cases/templates/S3DeepStorage.py b/integration-tests-ex/cases/cluster/S3DeepStorage/docker-compose.py
similarity index 100%
rename from integration-tests-ex/cases/templates/S3DeepStorage.py
rename to integration-tests-ex/cases/cluster/S3DeepStorage/docker-compose.py
diff --git a/integration-tests-ex/cases/cluster/S3DeepStorage/verify.sh b/integration-tests-ex/cases/cluster/S3DeepStorage/verify.sh
new file mode 100644
index 000000000000..ba2b3e507ac1
--- /dev/null
+++ b/integration-tests-ex/cases/cluster/S3DeepStorage/verify.sh
@@ -0,0 +1,21 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#--------------------------------------------------------------------
+
+require_env_var DRUID_CLOUD_BUCKET
+require_env_var DRUID_CLOUD_PATH
+require_env_var AWS_REGION
+require_env_var AWS_ACCESS_KEY_ID
+require_env_var AWS_SECRET_ACCESS_KEY
diff --git a/integration-tests-ex/cases/templates/template.py b/integration-tests-ex/cases/cluster/template.py
similarity index 97%
rename from integration-tests-ex/cases/templates/template.py
rename to integration-tests-ex/cases/cluster/template.py
index 1be24ab032e4..015b5126e226 100644
--- a/integration-tests-ex/cases/templates/template.py
+++ b/integration-tests-ex/cases/cluster/template.py
@@ -23,7 +23,7 @@
 PyYaml does the grunt work of converting the data structure to the YAML file.
 '''
 
-import yaml, os, os.path
+import yaml, os
 from pathlib import Path
 
 # Constants used frequently in the template.
@@ -49,15 +49,16 @@ def generate(template_path, template):
     '''
 
     # Compute the cluster (test category) name from the template path which
-    # we assume to be module/<something>/<template>/<something>.py
+    # we assume to be <module>/templates/<something>.py
     template_path = Path(template_path)
-    cluster = template_path.stem
+    cluster = template_path.parent.name
 
-    # Move up to the module (that is, the cases folder) relative to the template file.
-    module_dir = Path(__file__).parent.parent
+    # Move up to the module relative to the template file.
+    module_dir = template_path.parent.parent.parent
 
     # The target location for the output file is <module>/target/cluster/<cluster>/docker-compose.yaml
     target_dir = module_dir.joinpath("target")
+    os.makedirs(target_dir, exist_ok=True)
     target_file = target_dir.joinpath('cluster', cluster, 'docker-compose.yaml')
 
     # Defer back to the template class to create the output into the docker-compose.yaml file.
@@ -205,7 +206,7 @@ def add_env(self, service, var, value):
     def add_property(self, service, prop, value):
         '''
         Sets a property for a service. The property is of the same form as the
-        .properties file: druid.some.property.
+        runtime.properties file: druid.some.property.
         This method converts the property to the env var form so you don't have to.
         '''
         var = prop.replace('.', '_')
@@ -230,7 +231,7 @@ def add_port(self, service, local, container):
         Add a port mapping to the service
         '''
         ports = service.setdefault('ports', [])
-        ports.append(local + ':' + container)
+        ports.append(str(local) + ':' + str(container))
 
     def define_external_service(self, name) -> dict:
         '''
diff --git a/integration-tests-ex/docs/compose.md b/integration-tests-ex/docs/compose.md
index c66279e816e5..8f0e2145e913 100644
--- a/integration-tests-ex/docs/compose.md
+++ b/integration-tests-ex/docs/compose.md
@@ -37,10 +37,38 @@ See also:
 
 ## File Structure
 
-Docker Compose files live in the `druid-it-cases` module (`test-cases` folder)
+Docker Compose files live in the `druid-it-cases` module (`cases` folder)
 in the `cluster` directory. There is a separate subdirectory for each cluster type
 (subset of test categories), plus a `Common` folder for shared files.
 
+### Cluster Directory
+
+Each test category uses an associated cluster. In some cases, multiple tests use
+the same cluster definition. Each cluster is defined by a directory in
+`$MODULE/cluster/$CLUSTER_NAME`. The directory contains a variety of files, most
+of which are optional:
+
+* `docker-compose.yaml` - Docker composes file, if created explicitly.
+* `docker-compose.py` - Docker compose "template" if generated. The Python template
+  format is preferred. (One of the `docker-compose.*` files is required)
+* `verify.sh` - Verify the environment for the cluster. Cloud tests require that a
+  number of environment variables be set to pass keys and other setup to tests.
+  (Optional)
+* `setup.sh` - Additional cluster setup, such as populating the "shared" directory
+  with test-specific items. (Optional)
+
+The `verify.sh` and `setup.sh` scripts are sourced into one of the "master"
+scripts and can thus make use of environment variables already set:
+
+* `BASE_MODULE_DIR` points to `integration-tests-ex/cases` where the "base" set
+  of scripts and cluster definitions reside.
+* `MODULE_DIR` points to the Maven module folder that contains the test.
+* `CATEGORY` gives the name of the test category.
+* `DRUID_INTEGRATION_TEST_GROUP` is the cluster name. Often the same as `CATEGORY`,
+  but not always.
+
+The `set -e` option is in effect so that an any errors fail the test.
+
 ## Shared Directory
 
 Each test has a "shared" directory that is mounted into each container to hold things
diff --git a/integration-tests-ex/docs/docker.md b/integration-tests-ex/docs/docker.md
index e030b45e5535..411e7ac5bb7d 100644
--- a/integration-tests-ex/docs/docker.md
+++ b/integration-tests-ex/docs/docker.md
@@ -211,6 +211,37 @@ when it starts. If you start, then restart the MySQL container, you *must*
 remove the `db` directory before restart or MySQL will fail due to existing
 files.
 
+### Per-test Extensions
+
+The image build includes a standard set of extensions. Contrib or custom extensions
+may wish to add additional extensions. This is most easily done not by altering the
+image, but by adding the extensions at cluster startup. If the shared directory has
+an `extensions` subdirectory, then that directory is added to the extension search
+path on container startup. To add an extension `my-extension`, your shared directory
+should look like this:
+
+```text
+shared
++- ...
++- extensions
+   +- my-extension
+      +- my-extension-<version>.jar
++- ...
+```
+
+The `extensions` directory should be created within the per-cluster `setup.sh` script
+which is when starting your test cluster.
+
+Be sure to also include the extension in the load list in your `docker-compose.py` template.
+To load the extension on all nodes:
+
+```python
+    def extend_druid_service(self, service):
+        self.add_env(service, 'druid_test_loadList', 'my-extension')
+```
+
+Note that the above requires Druid and IT features added in early March, 2023.
+
 ### Third-Party Logs
 
 The three third-party containers are configured to log to the `/shared`
diff --git a/integration-tests-ex/image/docker/launch.sh b/integration-tests-ex/image/docker/launch.sh
index 8116ab963231..db9f67e380f7 100644
--- a/integration-tests-ex/image/docker/launch.sh
+++ b/integration-tests-ex/image/docker/launch.sh
@@ -22,15 +22,34 @@
 # Fail fast on any error
 set -e
 
-# Enable for tracing
+# Enable for debugging
 #set -x
 
-# Dump the environment for debugging.
+# Dump the environment for debugging. Also done later to the log.
 #env
 
 # Launch Druid within the container.
 cd /
 
+# Where things are located
+SHARED_DIR=/shared
+LOG_DIR=$SHARED_DIR/logs
+DRUID_HOME=/usr/local/druid
+
+# Allow test-specific extensions in the /shared/extensions directory.
+# If that directory exists (it won't for most tests), add it to the
+# extensions path, using a feature in Druid 26 or later.
+# For maximum flexibility, don't overwrite the extensions path if
+# it is set.
+TEST_EXTN_DIR=$SHARED_DIR/extensions
+if [ -d $TEST_EXTN_DIR ]; then
+  if [ -z "$druid_extensions_path" ]; then
+    export druid_extensions_path="[\"${TEST_EXTN_DIR}\"]"
+  else
+    echo "Extension directory $TEST_EXTN_DIR found, and druid_extensions_path={$druid_extensions_path} -- not setting path automatically"
+  fi
+fi
+
 # TODO: enable only for security-related tests?
 #/tls/generate-server-certs-and-keystores.sh
 
@@ -38,12 +57,12 @@ cd /
 # The MySQL driver is selected by the Docker Compose file.
 # Set  druid.metadata.mysql.driver.driverClassName to the preferred
 # driver.
-
-# Test-specific way to define extensions. Compose defines two test-specific
-# variables. We combine these to create the final form converted to a property.
 if [ -n "$MYSQL_DRIVER_CLASSNAME" ]; then
   export druid_metadata_mysql_driver_driverClassName="$MYSQL_DRIVER_CLASSNAME"
 fi
+
+# Test-specific way to define extensions. Compose defines two test-specific
+# variables. We combine these to create the final form converted to a property.
 if [ -n "$druid_extensions_loadList" ]; then
 	echo "Using the provided druid_extensions_loadList=$druid_extensions_loadList"
 else
@@ -76,10 +95,6 @@ DRUID_SERVICE_CONF_DIR="$(. /druid.sh; getConfPath ${DRUID_SERVICE})"
 # Export the common config file path to use in supervisord conf file
 DRUID_COMMON_CONF_DIR="$(. /druid.sh; getConfPath _common)"
 
-SHARED_DIR=/shared
-LOG_DIR=$SHARED_DIR/logs
-DRUID_HOME=/usr/local/druid
-
 # For multiple nodes of the same type to create a unique name
 INSTANCE_NAME=$DRUID_SERVICE
 if [ -n "$DRUID_INSTANCE" ]; then
@@ -117,6 +132,8 @@ if [ -d $EXTRA_RESOURCES ]; then
 	CP=$CP:$EXTRA_RESOURCES
 fi
 
+# For easier debugging, dump the environment and runtime.properties
+# to the log.
 LOG_FILE=$LOG_DIR/${INSTANCE_NAME}.log
 echo "" >> $LOG_FILE
 echo "--- env ---" >> $LOG_FILE
diff --git a/it.sh b/it.sh
index 2c6aa86062e5..ce4e8e8483e1 100755
--- a/it.sh
+++ b/it.sh
@@ -30,7 +30,7 @@ export DRUID_DEV=$(cd $(dirname $0) && pwd)
 function usage
 {
   cat <<EOF
-Usage: $0 cmd [category]
+Usage: $0 cmd [category] [module]
   ci
       build Druid and the distribution for CI pipelines
   build
@@ -41,21 +41,32 @@ Usage: $0 cmd [category]
       Build druid-it-tools
   image
       Build the test image
-  up <category>
-      Start the cluster for category
-  down <category>
-      Stop the cluster for category
-  test <category>
-      Start the cluster, run the test for category, and stop the cluster
-  tail <category>
-      Show the last 20 lines of each container log
-  gen
+  up <category> [<module>]
+      Start the cluster for category.
+  down <category> [<module>]
+      Stop the cluster for category.
+  run <category> [<module>]
+      Run the tests for the given module on an alread-running cluster.
+      Does not stop the cluster. Primarily for debugging.
+  test <category> [<module>]
+      Start the cluster, run the test for category, and stop the cluster.
+  tail <category> [<module>]
+      Show the last 20 lines of each container log.
+  gen <category> [<module>]
       Generate docker-compose.yaml files (done automatically on up)
-      run one IT in Travis (build dist, image, run test, tail logs)
-  github <category>
-      Run one IT in Github Workflows (run test, tail logs)
-  prune
-      prune Docker volumes
+      run one IT in Travis (build dist, image, run test, tail logs).
+  github <category> [<module>]
+      Run one IT in Github Workflows (run test, tail logs).
+  prune-containers
+      Stop all running Docker containers. Do this if "down" won't work
+      because the "docker-compose.yaml" file is no longer available.
+  prune-volumes
+      prune Docker volumes.
+
+Arguments:
+  category: A defined IT JUnit category, and IT-<category> profile
+  module: relative path to the module with tests. Defaults to
+          integration-tests-ex/cases
 
 Environment:
   OVERRIDE_ENV: optional, name of env file to pass to Docker
@@ -70,13 +81,13 @@ EOF
 
 function tail_logs
 {
-  category=$1
-  cd integration-tests-ex/cases/target/$category/logs
+  pushd $MODULE_DIR/target/$CATEGORY/logs > /dev/null
   ls *.log | while read log;
   do
-    echo "----- $category/$log -----"
-    tail -20 $log
+    echo "----- $CATEGORY/$log -----"
+    tail -100 $log
   done
+  popd > /dev/null
 }
 
 # Many tests require us to pass information into containers using environment variables.
@@ -100,10 +111,13 @@ function tail_logs
 #
 # All of the above are combined into a temporary environment file which is then passed
 # into Docker compose.
+#
+# The file is built when the cluster comes up. It is reused in the test and down
+# commands so we have a consistent environment.
 function build_override {
 
-	mkdir -p target
-	OVERRIDE_FILE="$(pwd)/target/override.env"
+	mkdir -p "$MODULE_DIR/target"
+	OVERRIDE_FILE="$MODULE_DIR/target/override.env"
 	rm -f "$OVERRIDE_FILE"
 	touch "$OVERRIDE_FILE"
 
@@ -122,36 +136,39 @@ function build_override {
 		cat "$LOCAL_ENV" >> "$OVERRIDE_FILE"
 	fi
 
-    # Add all environment variables of the form druid_*
-    set +e # Grep gives exit status 1 if no lines match. Let's not fail.
-    env | grep "^druid_" >> "$OVERRIDE_FILE"
-    set -e
+  # Add all environment variables of the form druid_*
+  set +e # Grep gives exit status 1 if no lines match. Let's not fail.
+  env | grep "^druid_" >> "$OVERRIDE_FILE"
+  set -e
 
-    # TODO: Add individual env vars that we want to pass from the local
-    # environment into the container.
+  # TODO: Add individual env vars that we want to pass from the local
+  # environment into the container.
 
-    # Reuse the OVERRIDE_ENV variable to pass the full list to Docker compose
-    export OVERRIDE_ENV="$OVERRIDE_FILE"
+  # Reuse the OVERRIDE_ENV variable to pass the full list to Docker compose
+  export OVERRIDE_ENV="$OVERRIDE_FILE"
 }
 
-function prepare_category {
-	if [ $# -eq 0 ]; then
+function reuse_override {
+  OVERRIDE_FILE="$MODULE_DIR/target/override.env"
+  if [ ! -f "$OVERRIDE_FILE" ]; then
+      echo "Override file $OVERRIDE_FILE not found: Was an 'up' run?" 1>&2
+      exit 1
+  fi
+  export OVERRIDE_ENV="$OVERRIDE_FILE"
+}
+
+function require_category {
+	if [ -z "$CATEGORY" ]; then
 		usage 1>&2
 		exit 1
 	fi
-	export CATEGORY=$1
-}
-
-function prepare_docker {
-    cd $DRUID_DEV/integration-tests-ex/cases
-    build_override
 }
 
 function require_env_var {
 	if [ -z "$1" ]; then
 	  echo "$1 must be set for test category $CATEGORY" 1>&2
 	  exit 1
-    fi
+  fi
 }
 
 # Verfiy any test-specific environment variables that must be set in this local
@@ -161,52 +178,64 @@ function require_env_var {
 # ensures we get useful error messages when we forget to set something, rather than
 # some cryptic use-specific error.
 function verify_env_vars {
-	case $CATEGORY in
-		"AzureDeepStorage")
-			require_env_var AZURE_ACCOUNT
-			require_env_var AZURE_KEY
-			require_env_var AZURE_CONTAINER
-			;;
-		"GcsDeepStorage")
-			require_env_var GOOGLE_BUCKET
-			require_env_var GOOGLE_PREFIX
-			require_env_var GOOGLE_APPLICATION_CREDENTIALS
-			if [ ! -f "$GOOGLE_APPLICATION_CREDENTIALS" ]; then
-				echo "Required file GOOGLE_APPLICATION_CREDENTIALS=$GOOGLE_APPLICATION_CREDENTIALS is missing" 1>&2
-				exit 1
-		    fi
-			;;
-		"S3DeepStorage")
-			require_env_var DRUID_CLOUD_BUCKET
-			require_env_var DRUID_CLOUD_PATH
-			require_env_var AWS_REGION
-			require_env_var AWS_ACCESS_KEY_ID
-			require_env_var AWS_SECRET_ACCESS_KEY
-			;;
-	esac
+  VERIFY_SCRIPT="$MODULE_DIR/cluster/$DRUID_INTEGRATION_TEST_GROUP/verify.sh"
+  if [ -f "$VERIFY_SCRIPT" ]; then
+    . "$VERIFY_SCRIPT"
+  fi
 }
 
-if [ $# = 0 ]; then
+if [ $# -eq 0 ]; then
   usage
   exit 1
 fi
 
 CMD=$1
 shift
-MAVEN_IGNORE="-P skip-static-checks,skip-tests -Dmaven.javadoc.skip=true"
+if [ $# -gt 0 ]; then
+	CATEGORY=$1
+	shift
+fi
+
+# Handle an IT in either the usual druid-it-cases project, or elsewhere,
+# typically in an extension. The Maven module, if needed must be the third
+# parameter in path, not coordinate, form.
+if [ $# -eq 0 ]; then
+  # Use the usual project
+  MAVEN_PROJECT=":druid-it-cases"
+  # Don't provide a project path to cluster.sh
+  unset IT_MODULE_DIR
+  # Generate the override.sh file in the druid-it-cases module
+  MODULE_DIR=$DRUID_DEV/integration-tests-ex/cases
+else
+  # The test module is given via the command line argument as a relative path
+  MAVEN_PROJECT="$1"
+  # Compute the full path to the target module for use by cluster.sh
+  export IT_MODULE_DIR="$DRUID_DEV/$1"
+  # Write the override.sh file to the target module
+  MODULE_DIR=$IT_MODULE_DIR
+  shift
+fi
+
+IT_CASES_DIR="$DRUID_DEV/integration-tests-ex/cases"
+
+# Added -Dcyclonedx.skip=true to avoid ISO-8859-1 [ERROR]s
+# May be fixed in the future
+MAVEN_IGNORE="-P skip-static-checks,skip-tests -Dmaven.javadoc.skip=true -Dcyclonedx.skip=true"
+TEST_OPTIONS="verify -P skip-static-checks,docker-tests \
+            -Dmaven.javadoc.skip=true -Dcyclonedx.skip=true -DskipUTs=true"
 
 case $CMD in
   "help" )
     usage
     ;;
   "ci" )
-    mvn -q clean package dependency:go-offline -P dist $MAVEN_IGNORE
+    mvn -q clean install dependency:go-offline -P dist $MAVEN_IGNORE
     ;;
   "build" )
-    mvn clean package -P dist $MAVEN_IGNORE -T1.0C $*
+    mvn clean install -P dist $MAVEN_IGNORE -T1.0C $*
     ;;
   "dist" )
-    mvn package -P dist $MAVEN_IGNORE -pl :distribution
+    mvn install -P dist $MAVEN_IGNORE -pl :distribution
     ;;
   "tools" )
     mvn install -pl :druid-it-tools
@@ -218,44 +247,70 @@ case $CMD in
   "gen")
     # Generate the docker-compose.yaml files. Mostly for debugging
     # since the up command does generation implicitly.
-    prepare_category $1
-    prepare_docker
-    ./cluster.sh gen $CATEGORY
+    require_category
+    $IT_CASES_DIR/cluster.sh gen $CATEGORY
     ;;
   "up" )
-    prepare_category $1
-    prepare_docker
+    require_category
+    build_override
     verify_env_vars
-    ./cluster.sh up $CATEGORY
+    $IT_CASES_DIR/cluster.sh up $CATEGORY
     ;;
   "down" )
-    prepare_category $1
-    prepare_docker
-    ./cluster.sh down $CATEGORY
+    require_category
+    reuse_override
+    $IT_CASES_DIR/cluster.sh down $CATEGORY
+    ;;
+  "run" )
+    require_category
+    reuse_override
+    mvn $TEST_OPTIONS -P IT-$CATEGORY -pl $MAVEN_PROJECT
     ;;
   "test" )
-    prepare_category $1
-    prepare_docker
-    mvn verify -P skip-static-checks,docker-tests,IT-$CATEGORY \
-            -Dmaven.javadoc.skip=true -DskipUTs=true \
-            -pl :druid-it-cases
+    require_category
+    build_override
+    verify_env_vars
+    $IT_CASES_DIR/cluster.sh up $CATEGORY
+
+    # Run the test. On failure, still shut down the cluster.
+    # Return Maven's return code as the script's return code.
+    set +e
+    mvn $TEST_OPTIONS -P IT-$CATEGORY -pl $MAVEN_PROJECT
+    RESULT=$?
+    set -e
+    $IT_CASES_DIR/cluster.sh down $CATEGORY
+    exit $RESULT
     ;;
   "tail" )
-    prepare_category $1
-    tail_logs $CATEGORY
+    require_category
+    tail_logs
     ;;
   "github" )
-    prepare_category $1
+    set +e
     $0 test $CATEGORY
-    $0 tail $CATEGORY
+    RESULT=$?
+
+    # Include logs, but only for failures.
+    if [ $RESULT -ne 0 ]; then
+      $0 tail $CATEGORY
+    fi
+    exit $RESULT
+    ;;
+  # Name is deliberately long to avoid accidental use.
+  "prune-containers" )
+    if [ $(docker ps | wc -l) -ne 1 ]; then
+      echo "Cleaning running containers"
+      docker ps
+      docker ps -aq | xargs -r docker rm -f
+    fi
     ;;
-  "prune" )
+  "prune-volumes" )
     # Caution: this removes all volumes, which is generally what you
     # want when testing.
-    docker system prune --volumes
+    docker system prune -af --volumes
     ;;
   * )
     usage
-    exit -1
+    exit 1
     ;;
 esac
diff --git a/server/src/main/java/org/apache/druid/server/QueryResultPusher.java b/server/src/main/java/org/apache/druid/server/QueryResultPusher.java
index 947283fe2bbc..ad268a78ef0f 100644
--- a/server/src/main/java/org/apache/druid/server/QueryResultPusher.java
+++ b/server/src/main/java/org/apache/druid/server/QueryResultPusher.java
@@ -297,7 +297,7 @@ public interface ResultsWriter extends Closeable
     /**
      * Gets the results of running the query.  {@link #start} must be called before this method is called.
      *
-     * @return the results of running the query as preparted by the {@link #start()} method
+     * @return the results of running the query as prepared by the {@link #start()} method
      */
     QueryResponse<Object> getQueryResponse();
 
diff --git a/services/src/main/java/org/apache/druid/cli/PullDependencies.java b/services/src/main/java/org/apache/druid/cli/PullDependencies.java
index 9b4f30ccc416..fb16422855aa 100644
--- a/services/src/main/java/org/apache/druid/cli/PullDependencies.java
+++ b/services/src/main/java/org/apache/druid/cli/PullDependencies.java
@@ -64,7 +64,6 @@
 import java.util.Set;
 import java.util.stream.Collectors;
 
-
 @Command(
     name = "pull-deps",
     description = "Pull down dependencies to the local repository specified by druid.extensions.localRepository, extensions directory specified by druid.extensions.extensionsDir and hadoop dependencies directory specified by druid.extensions.hadoopDependenciesDir"
@@ -88,39 +87,38 @@ public class PullDependencies implements Runnable
                   .put("com.fasterxml.jackson.core", "jackson-annotations")
                   .build();
    /*
+      It is possible that extensions will pull down a lot of jars that are either
+      duplicates OR conflict with druid jars. In that case, there are two problems that arise
+
+      1. Large quantity of jars are passed around to things like hadoop when they are not needed (and should not be included)
+      2. Classpath priority becomes "mostly correct" and attempted to enforced correctly, but not fully tested
+
+      These jar groups should be included by druid and *not* pulled down in extensions
+      Note to future developers: This list is hand-crafted and will probably be out of date in the future
+      A good way to know where to look for errant dependencies is to compare the lib/ directory in the distribution
+      tarball with the jars included in the extension directories.
+
+      This list is best-effort, and might still pull down more than desired.
+
+      A simple example is that if an extension's dependency uses some-library-123.jar,
+      druid uses some-library-456.jar, and hadoop uses some-library-666.jar, then we probably want to use some-library-456.jar,
+      so don't pull down some-library-123.jar, and ask hadoop to load some-library-456.jar.
+
+      In the case where some-library is NOT on this list, both some-library-456.jar and some-library-123.jar will be
+      on the class path and propagated around the system. Most places TRY to make sure some-library-456.jar has
+      precedence, but it is easy for this assumption to be violated and for the precedence of some-library-456.jar,
+      some-library-123.jar and some-library-456.jar to not be properly defined.
+
+      As of this writing there are no special unit tests for classloader issues and library version conflicts.
+
+      Different tasks which are classloader sensitive attempt to maintain a sane order for loading libraries in the
+      classloader, but it is always possible that something didn't load in the right order. Also we don't want to be
+      throwing around a ton of jars we don't need to.
+
+      Here is a list of dependencies extensions should probably exclude.
 
-      // It is possible that extensions will pull down a lot of jars that are either
-      // duplicates OR conflict with druid jars. In that case, there are two problems that arise
-      //
-      // 1. Large quantity of jars are passed around to things like hadoop when they are not needed (and should not be included)
-      // 2. Classpath priority becomes "mostly correct" and attempted to enforced correctly, but not fully tested
-      //
-      // These jar groups should be included by druid and *not* pulled down in extensions
-      // Note to future developers: This list is hand-crafted and will probably be out of date in the future
-      // A good way to know where to look for errant dependencies is to compare the lib/ directory in the distribution
-      // tarball with the jars included in the extension directories.
-      //
-      // This list is best-effort, and might still pull down more than desired.
-      //
-      // A simple example is that if an extension's dependency uses some-library-123.jar,
-      // druid uses some-library-456.jar, and hadoop uses some-library-666.jar, then we probably want to use some-library-456.jar,
-      // so don't pull down some-library-123.jar, and ask hadoop to load some-library-456.jar.
-      //
-      // In the case where some-library is NOT on this list, both some-library-456.jar and some-library-123.jar will be
-      // on the class path and propagated around the system. Most places TRY to make sure some-library-456.jar has
-      // precedence, but it is easy for this assumption to be violated and for the precedence of some-library-456.jar,
-      // some-library-123.jar and some-library-456.jar to not be properly defined.
-      //
-      // As of this writing there are no special unit tests for classloader issues and library version conflicts.
-      //
-      // Different tasks which are classloader sensitive attempt to maintain a sane order for loading libraries in the
-      // classloader, but it is always possible that something didn't load in the right order. Also we don't want to be
-      // throwing around a ton of jars we don't need to.
-      //
-      // Here is a list of dependencies extensions should probably exclude.
-      //
-      // Conflicts can be discovered using the following command on the distribution tarball:
-      //    `find lib -iname "*.jar" | cut -d / -f 2 | sed -e 's/-[0-9]\.[0-9]/@/' | cut -f 1 -d @ | sort | uniq | xargs -I {} find extensions -name "*{}*.jar" | sort`
+      Conflicts can be discovered using the following command on the distribution tarball:
+         `find lib -iname "*.jar" | cut -d / -f 2 | sed -e 's/-[0-9]\.[0-9]/@/' | cut -f 1 -d @ | sort | uniq | xargs -I {} find extensions -name "*{}*.jar" | sort`
 
       "org.apache.druid",
       "com.metamx.druid",
diff --git a/sql/pom.xml b/sql/pom.xml
index 9ab3226f2e2a..eb2c1bf7a39c 100644
--- a/sql/pom.xml
+++ b/sql/pom.xml
@@ -395,7 +395,7 @@
         </configuration>
       </plugin>
 
-      <!-- Adds the path of the generated parser to the classpath -->
+      <!-- Adds the path of the generated parser to the build path -->
       <plugin>
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>build-helper-maven-plugin</artifactId>