PG::ConnectionBad (could not connect to server: No such file or directory
     Is the server running locally and accepting
     connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
 ):

version: '2'
services:
  users:
    build:
      context: '.'
    links:
      - postgres
      - redis
    volumes:
     - ".:/app/users/"
    working_dir: /app/users
    command: [rails, server, -p, "3000", -b, 0.0.0.0]
    ports:
    - "3000:3000"

  postgres:
    image: postgres:9.5
    environment:
      POSTGRES_DB: somedb
      POSTGRES_USER: someuser
      POSTGRES_PASSWORD: somepass

  redis:
    image: redis:latest
    command: redis-server
    ports:
      - "6379:6379"
    volumes:
      - "redis:/var/lib/redis/data"

volumes:
  redis:

development:
  <<: *default
  database: somedb
  user: someuser
  password: somepass
  host: postgres
  port: 5432