Software that federates via OStatus

free and open source software microblogging server

Friendica (formerly Friendika, originally Mistpark) is a free and open-source software distributed social network. It forms one part of the Fediverse, an interconnected and decentralized network of independently operated servers.

OStatus is an open standard for decentralized social networking, allowing users on one service to send and receive status updates with users from another. The standard describes how a suite of various standards, including Atom, Activity Streams, WebSub, Salmon, and WebFinger, can be used together, which enables different microblogging server implementations to communicate status updates between their users back-and-forth, in near real-time.