Best thing would be a new registry like composer https://packagist.org https://packagist.org that is just a resolver to another server e.g. github. So in the d

Best thing would be a new registry like composer https://packagist.org https://packagist.org that is just a resolver to another server e.g. github. So in the docker file you write XYZ/dockerimg and the registry redirect to the mapped correct docker registry.