version: '3' services: db: container_name: db image: postgres:11 volumes: - data:/var/lib/postgresql/data web: container_name: app command: bundle exec unicorn -c config/unicorn.rb entrypoint: bin/wait-for-it.sh db:5432 -s -- environment: DATABASE_URL: postgres://postgres@db/postgres expose: - '8080' links: - db volumes: data: