I want a replacement for GitHub.

I think that's it. Git is already "federated" in that anybody can pull from a public repository. You can't push, however. In order to do that, you need to send your patch via email. There are no federated pull requests. But then again, I was very confused by the concept when I got started with GitHub. I don't think I need that.

I'm using cgit to allow browsing the source code on the web.