Redlib

Federated microblogging server.

Advanced forum / community solution based on Ruby and JS.

Delightfully simple forums. Flarum is the next-generation forum software that makes online discussion fun again.

Knowledge-based community software. You can use it to quickly build your Q&A community for product technical support, customer support, user communication, and more.

Forum software built for the modern web.

Link aggregator for the fediverse (alternative to Reddit).

Distributed social networking server.

An alternative front end to twitter.

Decentralized app-like microblogging server/SNS for the Fediverse, using the ActivityPub protocol like GNU social and Mastodon.

Ethical photo sharing platform, powered by ActivityPub federation (alternative to Instagram).

Flexible kit for private social networks.

Lightweight and simple comment engine, which doesn't spy on users. It can be embedded into blogs, articles or any other place where readers add comments.