Mastodon is written as a free, web-based software for federated microblogging, which anybody can contribute code to, and which anyone can run on their own server infrastructure, if they wish, or join servers run by other people[23] within the fediverse network.[24] Its server-side technology is powered by Ruby on Rails and Node.js, and its front end is written in React.js and Redux.[25] The database software is PostgreSQL.[26] The service is interoperable with the decentralized social networks and platforms which use the ActivityPub protocol between each other.[27] Since version 3.0, Mastodon dropped previous support for OStatus.[28] [29]