diff --git a/changelog.d/12280.misc b/changelog.d/12280.misc
new file mode 100644
index 0000000000..bdc00b821a
--- /dev/null
+++ b/changelog.d/12280.misc
@@ -0,0 +1 @@
+Add missing type definitions for scripts in docker folder. Contributed by Jorge Florian.
diff --git a/docker/configure_workers_and_start.py b/docker/configure_workers_and_start.py
index adbb551cee..4d5e94ad6f 100755
--- a/docker/configure_workers_and_start.py
+++ b/docker/configure_workers_and_start.py
@@ -29,6 +29,7 @@
 import os
 import subprocess
 import sys
+from typing import Any, Dict, Set
 
 import jinja2
 import yaml
@@ -36,7 +37,7 @@ import yaml
 MAIN_PROCESS_HTTP_LISTENER_PORT = 8080
 
 
-WORKERS_CONFIG = {
+WORKERS_CONFIG: Dict[str, Dict[str, Any]] = {
     "pusher": {
         "app": "synapse.app.pusher",
         "listener_resources": [],
@@ -355,7 +356,7 @@ def generate_worker_files(environ, config_path: str, data_dir: str):
     #   worker_type: {1234, 1235, ...}}
     # }
     # and will be used to construct 'upstream' nginx directives.
-    nginx_upstreams = {}
+    nginx_upstreams: Dict[str, Set[int]] = {}
 
     # A map of: {"endpoint": "upstream"}, where "upstream" is a str representing what will be
     # placed after the proxy_pass directive. The main benefit to representing this data as a
@@ -384,7 +385,7 @@ def generate_worker_files(environ, config_path: str, data_dir: str):
     # A counter of worker_type -> int. Used for determining the name for a given
     # worker type when generating its config file, as each worker's name is just
     # worker_type + instance #
-    worker_type_counter = {}
+    worker_type_counter: Dict[str, int] = {}
 
     # For each worker type specified by the user, create config values
     for worker_type in worker_types:
@@ -404,7 +405,7 @@ def generate_worker_files(environ, config_path: str, data_dir: str):
         # e.g. federation_reader1
         worker_name = worker_type + str(new_worker_count)
         worker_config.update(
-            {"name": worker_name, "port": worker_port, "config_path": config_path}
+            {"name": worker_name, "port": str(worker_port), "config_path": config_path}
         )
 
         # Update the shared config with any worker-type specific options
diff --git a/mypy.ini b/mypy.ini
index 1f33246417..3d20d99a94 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -11,6 +11,7 @@ local_partial_types = True
 no_implicit_optional = True
 
 files =
+  docker/,
   scripts-dev/,
   setup.py,
   synapse/,