traefik/integration/resources/compose/tlsclientheaders.yml

whoami:
    image: containous/whoami
    labels:
      - traefik.frontend.passTLSClientCert.pem=true
      - traefik.routers.route1.rule=PathPrefix(`/`)
      - traefik.routers.route1.middlewares=passtls
      - traefik.middlewares.passtls.passtlsclientcert.pem=true