diff --git a/docker-compose.coolify.yml b/docker-compose.coolify.yml
index 79ad89f..3ab3d7a 100644
--- a/docker-compose.coolify.yml
+++ b/docker-compose.coolify.yml
@@ -16,11 +16,27 @@
 #   - `coolify` network is created by Coolify; we attach so containers can
 #     reach the TimescaleDB by service name.
 
+# The TimescaleDB this app talks to lives in another Coolify project
+# (its compose network is `bo3nov2ija7g8wn9b1g2paxs`). The DB container
+# has the alias `timescale_db` ONLY on that network, so we attach all
+# three services to it as an external network — that's what makes the
+# DATABASE_URL `postgresql://...@timescale_db:5432/fleet_platform` work.
+#
+# If/when the DB project is re-created with a different network UUID,
+# update the name here OR migrate the DB onto the shared `coolify` net.
+networks:
+  db_project:
+    name: bo3nov2ija7g8wn9b1g2paxs
+    external: true
+
 services:
   gateway:
     build: .
     image: fleet-platform:${COOLIFY_RESOURCE_UUID:-latest}
     restart: unless-stopped
+    networks:
+      - default
+      - db_project
     environment:
       APP_ROLE: gateway
       APP_MODE: prod
@@ -49,6 +65,9 @@ services:
     depends_on:
       gateway:
         condition: service_started
+    networks:
+      - default
+      - db_project
     environment:
       APP_ROLE: worker
       APP_MODE: prod
@@ -72,6 +91,9 @@ services:
     depends_on:
       gateway:
         condition: service_started
+    networks:
+      - default
+      - db_project
     environment:
       APP_ROLE: cron
       APP_MODE: prod