- [HumHub](https://www.humhub.org/) - Flexible kit for private social networks. ([Source Code](https://github.com/humhub/humhub)) `AGPL-3.0``PHP`
- [Isso](http://posativ.org/isso/) - Lightweight commenting server written in Python and Javascript. It aims to be a drop-in replacement for Disqus. ([Source Code](https://github.com/posativ/isso)) `MIT``Python`
- [Lemmy](https://join.lemmy.ml/#/) - A link aggregator / reddit clone for the fediverse. Reddit alternative built in Rust. ([Source Code](https://github.com/dessalines/lemmy)) `AGPL-3.0``Rust`
- [Libreddit](https://libredd.it/) `⚠` - Private front-end for Reddit written in Rust. ([Source Code](https://github.com/spikecodes/libreddit)) `AGPL-3.0``Rust`
- [Loomio](https://www.loomio.org/) - Loomio is a collaborative decision-making tool that makes it easy for anyone to participate in decisions which affect them. ([Source Code](https://github.com/loomio/loomio)) `AGPL-3.0``Ruby`
- [Mastodon](https://joinmastodon.org/) - Federated microblogging server, an alternative to GNU social. ([Source Code](https://github.com/tootsuite/mastodon)) `AGPL-3.0``Ruby`
- [Misago](https://misago-project.org/) - Misago is fully featured modern forum application that is fast, scalable and responsive. ([Source Code](https://github.com/rafalp/Misago)) `GPL-2.0``Python`