It seems like this app had a hassle free install and I don't have any tips so far. Just stick to the plan.

docker-compose.yml

  services:
    heimdall:
      image: ghcr.io/linuxserver/heimdall
      container_name: heimdall
      environment:
        - PUID=1000
        - PGID=1000
        - TZ=Europe/Athens
      volumes:
        - ${PWD}/config:/config
      ports:
        - 10080:80
        - 10443:443
      restart: unless-stopped
 
  version: "2.1"