Building a Mastodon Compatible Java Server for ActivityPub

ActivityPub is a decentralized social networking protocol that has gained significant attention from the media for its ability to communicate through the Fediverse, short for the federated web. Servers such as Mastodon implement the ActivityPub protocol to communicate over the Fediverse. In this paper, we deconstruct the core protocols used to build the distributed servers of the Fediverse. We explore Mastodon’s complex implementation of ActivityPub and created our own Mastodon instance using Java Spring Boot and ActivityPub to interoperate with Mastodon servers.