The space of software hosting forges is sizeable. Most techy people know about GitHub and GitLab but many software forges exist (if considering the entire world). Here’s a few of note.

1. NotABug: Based on Gogs.
2. SourceHut: Suite of free software development tools built from the ground up.
3. Codeberg: Based on Gitea.
4. SourceForge: Mainstream software hosting.
5. Radicle: Decentralized on the service layer (discussions/issues). Git itself is distributed and decentralized.
6. Savannah: Suite of software development tools from GNU.