diff --git a/docker-compose.test.yml b/docker-compose.test.yml
index d3c7978..3cedde7 100644
--- a/docker-compose.test.yml
+++ b/docker-compose.test.yml
@@ -39,7 +39,16 @@ services:
     # against a fresh database would build a stale schema the app cannot work with.
     # Bring the schema in with `pg_dump --schema-only` from production instead.
     environment:
-      HOSTNAME: "0.0.0.0"    
+      # Docker sets HOSTNAME=<container-id>, and the Next.js standalone server binds to
+      # that single interface. With two networks Caddy then cannot reach the container.
+      HOSTNAME: "0.0.0.0"
+      # `db` and `redis` are taken in BOTH networks - by this stack in test-internal and
+      # by production in qrmaster-network. Production wins the lookup every time, so the
+      # base file's hostnames point the staging app at the production instances. Container
+      # names are unique per daemon and cannot be shadowed.
+      DATABASE_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@qrmaster-test-db:5432/${POSTGRES_DB}?schema=public
+      DIRECT_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@qrmaster-test-db:5432/${POSTGRES_DB}?schema=public
+      REDIS_URL: redis://qrmaster-test-redis:6379
     entrypoint: ["node", "server.js"]
     build:
       args: