services:
  keepalive:
    build:
      context: .
    restart: unless-stopped
    # keepalive is a background worker: it opens no port and serves no HTTP,
    # so there is no `expose`, no `ports`, no domain and no healthcheck (the
    # distroless image has no shell or HTTP client to run one anyway).
    #
    # Every setting lives in the config file; the app reads no environment
    # variables. The real config holds datastore credentials, so never commit
    # it: locally, copy config.example.yml to config.yml; on Coolify, this bind
    # mount becomes an editable file storage.
    volumes:
      - ./config.yml:/config.yml:ro