version: '3.8'
networks:
  coolify:
    external: true
services:
  traefik:
    container_name: coolify-proxy
    image: 'traefik:v2.11'
    restart: unless-stopped
    extra_hosts:
      - 'host.docker.internal:host-gateway'
    networks:
      - coolify
    ports:
      - '80:80'
      - '443:443'
      - '8080:8080'
    healthcheck:
      test: 'wget -qO- http://localhost:80/ping || exit 1'
      interval: 4s
      timeout: 2s
      retries: 5
    environment:
      - 'INFOMANIAK_ACCESS_TOKEN=<token>
    volumes:
      - '/var/run/docker.sock:/var/run/docker.sock:ro'
      - '/data/coolify/proxy:/traefik'
    command:
      - '--ping=true'
      - '--ping.entrypoint=http'
      - '--api.dashboard=true'
      - '--api.insecure=false'
      - '--entrypoints.http.address=:80'
      - '--entrypoints.https.address=:443'
      - '--entrypoints.http.http.encodequerysemicolons=true'
      - '--entryPoints.http.http2.maxConcurrentStreams=50'
      - '--entrypoints.https.http.encodequerysemicolons=true'
      - '--entryPoints.https.http2.maxConcurrentStreams=50'
      - '--providers.docker.exposedbydefault=false'
      - '--providers.file.directory=/traefik/dynamic/'
      - '--providers.file.watch=true'
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge=true'
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge.resolvers=ns41.infomaniak.com,ns42.infomaniak.com'
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge.provider=infomaniak'
      - '--certificatesresolvers.letsencrypt.acme.storage=/traefik/acme.json'
      - '--certificatesresolvers.letsencrypt.acme.httpchallenge.entrypoint=http'
      - '--providers.docker=true'
    labels:
      - traefik.enable=true
      - traefik.http.routers.traefik.entrypoints=http
      - traefik.http.routers.traefik.service=api@internal
      - traefik.http.services.traefik.loadbalancer.server.port=8080
      - coolify.managed=true

In docker-compose.yml:

    # ...
    environment:
      - 'INFOMANIAK_ACCESS_TOKEN=<token>'
    # ...
    command:
      # ...
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge=true'
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge.resolvers=ns41.infomaniak.com,ns42.infomaniak.com'
      - '--certificatesresolvers.letsencrypt.acme.dnschallenge.provider=infomaniak'
      # ...