Mastodon

Mastodon is an open source social networking platform that enables users to join or create servers built around topics of interest, built by the company of the same name in Berlin. Mastodon provides users with the possibility of managing an audience without middlemen. Mastodon deployed on one's own infrastructure allows the user to follow and be followed from any other Mastodon server online, without a middleman. It is free to use and to establish a Mastodon server, under a AGPL-3.0 license.