If you don’t mind self hosting, I’ve used Gitea. There are no limits if you self host. I’ve also heard good things about self hosted Gitlab. If your looking for something remotely hosted like GitHub, though, I’m afraid I don’t know of any free services I would trust.

I think the OP is looking for something remote hosted.

Probably, though you may have to dig to find them. Lemmy is rapidly becoming like Reddit in that if something exists, there is probably a community for it. If your local search doesn’t bring anything up, I would check on lemmyverse.net. It seems to have indexed most if not all of the current communities. A quick search just now for “liberta” pulled up roughly 10 communities.