diff --git a/flake.nix b/flake.nix
index 31f283293971..8daf7b017b97 100644
--- a/flake.nix
+++ b/flake.nix
@@ -104,6 +104,7 @@
                   libxml2
                   libxslt
                   sqlite
+                  gcc
 
                   # Native dependencies for unit tests (SyTest also requires OpenSSL).
                   openssl
@@ -152,7 +153,7 @@
 
                 # Postgres is needed to run Synapse with postgres support and
                 # to run certain unit tests that require postgres.
-                services.postgres.enable = true;
+                services.postgres.enable = false;
 
                 # On the first invocation of `devenv up`, create a database for
                 # Synapse to store data in.
@@ -168,7 +169,7 @@
                 '';
 
                 # Redis is needed in order to run Synapse in worker mode.
-                services.redis.enable = true;
+                services.redis.enable = false;
 
                 # Configure and start Synapse. Before starting Synapse, this shell code:
                 #  * generates a default homeserver.yaml config file if one does not exist, and
@@ -178,22 +179,6 @@
                 process.before = ''
                   python -m synapse.app.homeserver -c homeserver.yaml --generate-config --server-name=synapse.dev --report-stats=no
                   mkdir -p homeserver-config-overrides.d
-                  cat > homeserver-config-overrides.d/database.yaml << EOF
-                  ## Do not edit this file. This file is generated by flake.nix
-                  database:
-                    name: psycopg2
-                    args:
-                      user: synapse_user
-                      database: synapse
-                      host: $PGHOST
-                      cp_min: 5
-                      cp_max: 10
-                  EOF
-                  cat > homeserver-config-overrides.d/redis.yaml << EOF
-                  ## Do not edit this file. This file is generated by flake.nix
-                  redis:
-                    enabled: true
-                  EOF
                 '';
                 # Start synapse when `devenv up` is run.
                 processes.synapse.exec = "poetry run python -m synapse.app.homeserver -c homeserver.yaml -c homeserver-config-overrides.d";
diff --git a/synapse/rest/media/create_resource.py b/synapse/rest/media/create_resource.py
index 84d6d9f1b955..c30438790c65 100644
--- a/synapse/rest/media/create_resource.py
+++ b/synapse/rest/media/create_resource.py
@@ -18,7 +18,8 @@
 
 from synapse.api.errors import LimitExceededError
 from synapse.api.ratelimiting import Ratelimiter
-from synapse.http.server import DirectServeJsonResource, respond_with_json
+from synapse.http.server import respond_with_json
+from synapse.http.servlet import RestServlet
 from synapse.http.site import SynapseRequest
 
 if TYPE_CHECKING:
@@ -28,7 +29,7 @@
 logger = logging.getLogger(__name__)
 
 
-class CreateResource(DirectServeJsonResource):
+class CreateResource(RestServlet):
     PATTERNS = [re.compile("/_matrix/media/v1/create")]
     isLeaf = True