gitlab-runner within docker systemd unit

docker-clean.service

[Unit]
Description=Cleanup and update docker image.
After=network.target docker.service
Requires=network.target docker.service

[Service]
ExecStartPre=/usr/bin/docker container prune -f
ExecStartPre=/usr/bin/docker image prune -f
ExecStartPre=/usr/bin/docker volume prune -f
ExecStartPre=/usr/bin/docker network prune -f
ExecStartPre=/usr/bin/docker system prune -f
ExecStart=/bin/sh -c 'docker image ls --format "{{.Repository}}:{{.Tag}}" | xargs -rI Y docker pull Y'
Type=oneshot

[Install]
WantedBy=multi-user.target

docker-compose.yml

version: '3.6'
services:
  runner:
    image: gitlab/gitlab-runner:alpine
    restart: always
    volumes:
      - type: tmpfs
        target: /home/gitlab-runner
        consistency: delegated
      - /var/run/docker.sock:/var/run/docker.sock:rw
      - ./etc:/etc/gitlab-runner:ro

gitlab-runner-restart.service

[Unit]
Description=Restart gitlab-runner service

[Service]
Type=oneshot
ExecStart=/usr/bin/systemctl try-restart gitlab-runner.service

gitlab-runner-restart.timer

[Unit]
Description=Restart gitlab-runner service to stay up2date

[Timer]
OnCalendar=daily
Persistent=true

[Install]
WantedBy=timers.target

gitlab-runner.service

[Unit]
Description=Start gitlab-runner
Requires=docker-clean.service

[Service]
WorkingDirectory=/srv/gitlab-runner
ExecStart=/usr/bin/docker-compose up --force-recreate
ExecStop=/usr/bin/docker-compose stop
Type=exec
Restart=always

[Install]
WantedBy=multi-user.target