mine-docker-compose.yml

db:
  image: postgres
  ports:
    - "5432"
redis:
  image: redis
  ports:
    - "6379"
sidekiq:
  build: ./mine-api
  command: bundle exec sidekiq
  links:
    - db
    - redis
  environment:
    REDIS_URL: redis://redis
    DIFFBOT_TOKEN: XXXXXXXXXXXXXXXXXXXXXXXXXXX
api:
  build: ./mine-api
  command: rails server -b 0.0.0.0
  environment:
    REDIS_URL: redis://redis
    DATABASE_HOST: 'db'
    DIFFBOT_TOKEN: XXXXXXXXXXXXXXXXXXXXXXXXXXX
  ports:
    - "3000:3000"
  links:
    - db
    - redis
  volumes:
    - ./mine-api:/usr/src/app
imagesearch:
  build: ./../go/src/github.com/mine-code/mine-search-api
  command: mine-search-api
  links:
    - db
  ports:
    - "5000:5000"
  environment:
    PORT: 5000
    TINEYE_USER: XXXXX
    TINEYE_PASSWORD: XXXXXXXXXXXX
    DATABASE_URL: 'postgres://postgres:@db:5432/media-genesis-api_development?sslmode=disable'

I have this file in a /mine folder called docker-compose.yml the contains all the individual repos. Some environment variables are still coming from the rails repo from an uncommitted .env.development file (example file is in the repo -- https://github.com/mine-code/mine-api/blob/master/.env.example). You can get the actual environment variables from through the Heroku dashboard for now.