version: "3.9"
services:
  tailscale:
    build:
      context: ../../images/tailscale
    environment:
      TAILSCALE_AUTH_KEY: ${TAILSCALE_AUTH_KEY:?err}
      TAILSCALE_HOSTNAME: ${TAILSCALE_HOSTNAME:-tailscale-docker-stateful-example}
      TAILSCALE_STATE_ARG: "/var/lib/tailscale_state/tailscale.state" # a file
    volumes:
      # a volume is used but it could be a local directory.
      - /var/lib/tailscale_state/
  some-service-1:
    image: nginxdemos/hello
    network_mode: "service:tailscale"