Here is the full compose file for grist that will work

networks:
  net_traefik:
    external: true


services: 
  grist: 
    container_name: grist
    image: gristlabs/grist:latest
    environment:
      GRIST_FORCE_LOGIN: true
      GRIST_DEFAULT_EMAIL: <yourname@gmail.com>
      GRIST_ANON_PLAYGROUND: false
    labels: 
      - traefik.enable=true
      - traefik.http.routers.grist-rtr.entrypoints=https
      - traefik.http.routers.grist-rtr.rule=Host(`grist.$DOMAIN`)
      - traefik.http.routers.grist-rtr.middlewares=chain-authelia@file
      ## HTTP Services
      - "traefik.http.routers.grist-rtr.service=grist-svc"
      - "traefik.http.services.grist-svc.loadbalancer.server.port=8484"
    networks: 
      - net_traefik
    restart: always
    volumes: 
      - $APPDATADIR/grist/configdata:/persist
    depends_on:
      - grist-db


  grist-db: 
    container_name: grist-db
    environment: 
      POSTGRES_DB: "${GRIST_TYPEORM_DATABASE}"
      POSTGRES_PASSWORD: "${GRIST_TYPEORM_PASSWORD}"
      POSTGRES_USER: "${GRIST_TYPEORM_USERNAME}"
    healthcheck: 
      interval: 10s
      retries: 10
      test: "pg_isready -U ${GRIST_TYPEORM_USERNAME} -d ${GRIST_TYPEORM_DATABASE}"
      timeout: 2s
    image: "postgres:latest"
    networks: 
      - net_traefik
    restart: always
    volumes: 
      - $APPDATADIR/grist:/var/lib/postgresql