diff --git a/awx/settings/defaults.py b/awx/settings/defaults.py
index 85d56728a3..30fa819d44 100644
--- a/awx/settings/defaults.py
+++ b/awx/settings/defaults.py
@@ -251,7 +251,7 @@ TEMPLATES = [
     },
 ]
 
-MIDDLEWARE_CLASSES = (  # NOQA
+MIDDLEWARE = (  # NOQA
     'awx.main.middleware.TimingMiddleware',
     'awx.main.middleware.MigrationRanCheckMiddleware',
     'corsheaders.middleware.CorsMiddleware',
@@ -628,7 +628,7 @@ AWX_REBUILD_SMART_MEMBERSHIP = False
 ALLOW_JINJA_IN_EXTRA_VARS = 'template'
 
 # Enable dynamically pulling roles from a requirement.yml file
-# when updating SCM projects 
+# when updating SCM projects
 # Note: This setting may be overridden by database settings.
 AWX_ROLES_ENABLED = True
 
diff --git a/awx/settings/development.py b/awx/settings/development.py
index 0de8314f28..3834c14cc4 100644
--- a/awx/settings/development.py
+++ b/awx/settings/development.py
@@ -162,3 +162,9 @@ except Exception:
     os.environ['SDB_NOTIFY_HOST'] = os.popen('ip route').read().split(' ')[2]
 
 WEBSOCKET_ORIGIN_WHITELIST = ['https://localhost:8043', 'https://localhost:3000']
+
+MIDDLEWARE = [
+    # ...
+    'debug_toolbar.middleware.DebugToolbarMiddleware',
+    # ...
+]