github_code/freeCodeCamp__freeCodeCamp/.devcontainer/docker-compose.yml

name: freecodecamp-devcontainer

services:
  devcontainer:
    image: ghcr.io/freecodecamp/devcontainer:latest
    # gatsby develop defaults to host `localhost`. Where the network namespace
    # has IPv6, glibc RFC 6724 precedence resolves that to ::1 first, so the
    # dev server binds IPv6 loopback only and port forwarding, which connects
    # over IPv4, is refused. 0.0.0.0 needs no AF_INET6 socket, so it also holds
    # where IPv6 is switched off.
    environment:
      GATSBY_HOST: 0.0.0.0
    volumes:
      - ..:/workspaces/freeCodeCamp:cached
    # Shares the db network namespace so MONGOHQ_URL and MAILPIT_HOST in
    # sample.env resolve on localhost. A service in that namespace cannot
    # publish a port, which is why the host ports live in a separate overlay.
    network_mode: service:db
    command: sleep infinity
    depends_on:
      db:
        condition: service_healthy
      setup:
        condition: service_completed_successfully
      mailpit:
        condition: service_started

  mailpit:
    # Same namespace, for MAILPIT_HOST=localhost.
    network_mode: service:db
    depends_on:
      db:
        condition: service_healthy