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Docker Compose Cheatsheet

Compose file keys and docker compose CLI commands for multi-container apps.

Compose file structure

services:
  web:
    image: nginx:1.27
    build: ./web          # or build: { context: ., dockerfile: Dockerfile }
    ports:
      - "8080:80"
    environment:
      NODE_ENV: production
    env_file: .env
    volumes:
      - app-data:/data
    depends_on:
      - db
    restart: unless-stopped
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost"]
      interval: 30s
      timeout: 5s
      retries: 3
    networks:
      - backend
    command: ["nginx", "-g", "daemon off;"]
    entrypoint: ["/docker-entrypoint.sh"]

networks:
  backend:
    driver: bridge

volumes:
  app-data:

Common service keys

Key Purpose
image Use pre-built image
build Build from Dockerfile
ports Publish host:container
expose Expose port to linked services only
environment / env_file Env vars
volumes Named volumes or bind mounts
depends_on Startup order (not readiness)
restart Restart policy
healthcheck Service health probe
networks Attach to networks
profiles Optional service groups
deploy.replicas Scale (Swarm / compatible setups)
secrets / configs Swarm-style secrets (where supported)

CLI commands

Command Description
docker compose up Create and start services
docker compose up -d Detached mode
docker compose down Stop and remove containers/networks
docker compose ps List service containers
docker compose logs -f SERVICE Follow logs
docker compose exec SERVICE sh Shell into service
docker compose build Build images
docker compose pull Pull images
docker compose config Validate and print resolved config
docker compose -f file.yml up Use alternate compose file
docker compose --profile dev up Start profile services

.env file

POSTGRES_PASSWORD=secret
APP_PORT=3000

Reference in compose: ${POSTGRES_PASSWORD}

Gotchas

  1. depends_on is not health-aware — Use healthcheck + condition: service_healthy where supported, or retry logic in apps.
  2. Compose v2 plugin — Use docker compose, not deprecated standalone docker-compose v1.
  3. Relative paths — Volume bind paths resolve from the compose file directory.
  4. Project name — Defaults to directory name; override with -p or COMPOSE_PROJECT_NAME.
  5. Rebuild after Dockerfile changes — Run docker compose build or up --build.

Deeper reading