If you’re looking for alternatives of Calibre and Jellyfin then storage of container image won’t be an issue for you. Whatever you want to access with Jellyfin will be likely much larger than all of the container images that you’re looking for combined.

Nice, like OpenSign, signdocs, contract or LibreSign?

Fonoster is planning to become a Twilio alternative.

They don’t have SMS support yet however.

You’re probably looking for Fonoster

I think that KanIDM can do this.