Docker Compose

docker compose up -d       # start all services in background
docker compose down        # stop and remove containers
docker compose logs -f app # follow logs for 'app' service
docker compose ps          # list running services

# docker-compose.yml
services:
  app:
    build: .
    ports:
      - "3000:3000"
    environment:
      DATABASE_URL: postgres://postgres:secret@db:5432/mydb
      REDIS_URL: redis://cache:6379
    depends_on:
      db:
        condition: service_healthy
      cache:
        condition: service_started
    volumes:
      - .:/app              # mount source for live reload
      - /app/node_modules   # don't override node_modules
 
  db:
    image: postgres:16-alpine
    environment:
      POSTGRES_PASSWORD: secret
      POSTGRES_DB: mydb
    volumes:
      - pg_data:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 5s
      timeout: 3s
      retries: 5
 
  cache:
    image: redis:7-alpine
    volumes:
      - redis_data:/data
 
volumes:
  pg_data:
  redis_data:

# .env (not committed to git)
POSTGRES_PASSWORD=secret
JWT_SECRET=supersecret

services:
  app:
    env_file:
      - .env

# docker-compose.override.yml (auto-loaded in dev)
services:
  app:
    command: npm run dev   # override prod CMD
    volumes:
      - .:/app