I've been looking to do this, but haven't found a good, easy to use pull thru proxy for docker, ghcr.io and some other registries. Most support docker only.

This one looks promising but overly complicated to set up.

A few times now, I've gone to restart a container and the repo's been moved, archived or paywalled. Other times, I'm running a few versions behind and the maintainer decided to not support it, but upgrading would mean a complete overhaul of my Helm values file. Ugh!

I was considering a docker registry on separate ports for each upstream registry I'd like to proxy/cache.