version: '3.4' services: demo: image: ${DOCKER_REGISTRY-}demo build: context: . dockerfile: Demo/Dockerfile async_monolith_demo_postgres: image: postgres:latest container_name: async_monolith_demo_postgres environment: POSTGRES_USER: postgres POSTGRES_PASSWORD: mypassword POSTGRES_DB: application ports: - "5442:5432" volumes: - async_monolith_demo_postgres:/var/lib/postgresql/data volumes: async_monolith_demo_postgres: