Proposed symbol for the Fediverse from 2018, the "fedigram"[1]
TheFediverse (commonly shortened tofedi)[2][3][4] is a collection ofsocial networking services that can communicate with each other (formally known asfederation) using a common protocol. Users of different websites can send and receive status updates,multimediafiles and other data across the network. The termFediverse is aportmanteau offederation anduniverse.[5]
The majority of Fediverse platforms are based onfree and open-source software, and create connections between servers using theActivityPub protocol. Some software still supports older federation protocols as well, such asOStatus, theDiaspora protocol and Zot, while newer protocols such asAT Protocol connect vianetwork bridges. Diaspora is the only actively developed software project classified under the original definition ofFediverse that does not support ActivityPub.[6][7]
While a traditional social networking service will host all its content on servers managed by the owner of the website, thedecentralized structure of the Fediverse allows any individual or organization to host a social platform using their own servers (referred to as an "instance").
Every instance is independent, and can set its own rules and expectations. Even so, much like how users of one email service such asGmail can still send emails to users of another service such asOutlook, users may still view content and interact with users on any other instance in the Fediverse. A user on oneMastodon instance, for example, may view and interact with posts made by a user on a different instance even if it is not running Mastodon.[8]
Instances hosted by different social networking services may also communicate with one another. A user on the microblogging platformMisskey, for example, may view and interact with posts made by users on Mastodon. Some Fediverse networks even allow users to interact with different social networking formats from the same platform. For example, a user on asocial news instance runningLemmy can interact with another post from an mbin instance, a similar service, as well as microblog statuses from Mastodon.[9][10]
Decentralized social networking platforms introduce new challenges and difficulties for usertrust and safety.[11][12] By nature of the Fediverse, operators of an instance are solely responsible for moderation of its content. As there is no form of centralized governance or moderation across the Fediverse, it is impossible for an instance to be "removed" from the Fediverse; it can only be defederated per an instance operator's choice, which makes that instance's content inaccessible from the operator's instance.[13] Individual instances are responsible for defining their own content policies, which may then be enforced by its staff. Moderation of a Fediverse instance differs significantly from that of traditional social media platforms, as moderators are responsible not only for content posted by users of that instance ("local users"), but also for content posted by users of other instances ("remote users").[12]
Excerpt of common protocols and platforms in the fediverse (2024)
The concept and the functionality of the Fediverse existed before theActivityPub protocol and the term itself. One of the first projects that included support for a decentralized social networking service was Laconica, amicroblogging platform which implemented theOpenMicroBlogging protocol for communicating between different installations of the software. The software was later renamed to StatusNet in 2009,[14] before being merged into theGNU social project in 2013 along with Free Social, with the two latter servers being a fork of StatusNet.[15][16]
Over time, the limitations of the OpenMicroBlogging protocol became more apparent, being designed as a one-way text messaging system.[17] To replace the ageing protocol,OStatus was devised as anopen standard for microblogging, combining various other technologies likeSalmon,Atom,WebSub andActivityStreams into a single protocol used for communicating between instances. StatusNet first implemented the OStatus protocol on March 3, 2010, with version 0.9.0, and OStatus quickly became the most popular federated protocol in usage.
Around the same time as OStatus was gaining popularity, theDiaspora social network was formed, using its own federated protocol. To illustrate the differences between the two protocols, the terms ofthe Fediverse andthe federation began to enter common usage, mainly after 2017. The term "the Fediverse" was used to describe the network formed by software using theOStatus protocol, such asGNU Social, Mastodon, andFriendica, in contrast to the competing diaspora protocol under "the federation".[18]
The various platforms of the Fediverse, as well as other federated networks, visualized as a tree
In December 2012, the flagship StatusNet instance at the time,identi.ca, transitioned away to a new software namedpump.io, with a new federation protocol to replace OStatus. The new protocol was designed to be useful for generalactivity streams and not just status updates, and replaced many of OStatus' external dependencies withJSON-LD and aREST API for its messaging and inbox systems, as well as making more use of ActivityStreams. While not as utilized as its OStatus predecessor, it would later become influential in the development of the ActivityPub standard.
In January 2018, theW3C presented the ActivityPub protocol as a recommended standard.[19] The standard aimed to improve the interoperability between different software packages running on a wide network of servers and to supersede both the OStatus protocol and Pump.io.[20] By 2019, almost all software that was using OStatus had added support for ActivityPub. While Mastodon began to remove OStatus support, other projects maintained it in their code, such asFriendica (which also maintained diaspora support along with ActivityPub).[21][22]
A major protocol often contrasted with ActivityPub is theAT Protocol, which powers theBluesky social network. While both protocols aim to create decentralized social networks, they employ different technical philosophies regarding user identity.
Developers of the AT Protocol, including Bluesky CEOJay Graber, have stated they chose not to use ActivityPub because it did not natively support easy "account portability", the ability for a user to move their account, data, and social graph to a new provider without relying on the original server to authorize the move.[23] In the ActivityPub model (used byMastodon), a user's identity is typically tied to a specific server, similar to an email address; if that server goes offline, the identity can be lost. The AT Protocol aims to solve this by separating identity from hosting, allowing users to switch providers without losing their identity.[24]
Although the two protocols are technically incompatible by default, third-party "bridges" such as Bridgy Fed have been developed to allow users on ActivityPub networks to follow and interact with users on the AT Protocol network, and vice versa.[25]
While the Fediverse has traditionally been the network most commonly referred to and used as an example regarding the subject ofdecentralized social networks, alternatives to it and the accompanying ActivityPub have been developed and deployed. Smaller competitors such asNostr and Farcaster have become popular within thecryptocurrency community.[26] These protocols have used ActivityPub as a frame of reference for which to design their own architecture, as these newer protocols use a different federation model based on publishing content to relays for distribution rather than ActivityPub's server-centric model.[27][28]
Despite their differences, software exists that permit thebridging of user content between these protocols, including "double-bridges" that span multiple protocols for the purpose of distributing the same content.[29][30]
Following theacquisition of Twitter by Elon Musk in November 2022, certain major social networks, includingThreads,[33][34]Tumblr andFlipboard, expressed interest in supporting the ActivityPub protocol, as a large number of users began to migrate toMastodon, a server that supports the Fediverse and was also the most popular alternative to Twitter at the time.Flickr also expressed support in supporting ActivityPub. As of November 2022[update], no information had been released by Flickr after the initial tweets by the CEO, with support for ActivityPub suspected to be on hold or cancelled.[35][36]
In 2024, the local government of theStary Sącz municipality in Poland launched their ownPeerTube instance[37] in order tode facto abolish its presence onYouTube. According to the government, they stopped using YouTube for official communications "in order to adhere to the appropriate regulations".[38] In the same year, VIVERSE,HTC Vive'smetaverse platform, implemented support for ActivityPub in their chat feature, allowing users to send direct messages to other fediverse users.[39]
Several European public bodies operate ActivityPub services. The European Commission hosts an official Mastodon instance.[40] The European Data Protection Supervisor (EDPS) published a data protection notice laying out the legal framework for operating a Mastodon service.[41] More recently, Mastodon offers paid support aimed at larger institutions.[42] However, the decentralized architecture of the network cannot centrally enforceage verification because verification data is left to individual server operators.[43]
WordPress has an officially supported plugin that integrates WordPress blogs into the Fediverse, allowing for comments to be exchanged between the comment section of a blog post and a Fediverse instance's reply function. The plugin was acquired by Automattic in March 2023,[44] and became available for allWordPress.com users in October of that same year.[45][46]
Ghost, a blogging platform and content management system, announced in April 2024 that they would be implementing Fediverse support via ActivityPub.[47][48][49] The feature had been highly requested on its forums.[50] In July 2024, Ghost started federating its development newsletter for the feature.[51]
Automattic CEOMatt Mullenweg tweeted in November 2022 thatTumblr was adding support for ActivityPub interoperability, in response to a user's complaints about Mastodon's complexity.[52] However, no further information was revealed for over a year, and the project was expected to be cancelled after a leaked reorganization that moved most of Tumblr's staff to other Automattic projects. However, following a question from aTechCrunch reporter during a questionnaire about the leaked memo, he revealed that the interoperability feature was not cancelled and that there was a small team working on studying the potential of implementing the protocol.[53] The plan was once again affirmed by Automattic in January 2025, with the ActivityPub plugin for WordPress most likely being the main method used for interoperability with the fediverse.[54]
The release ofThreads byMeta in July 2023 had included in its press release that it planned to support interoperability with the ActivityPub protocol.[55][56] In December 2023, select Meta employees began to federate with ActivityPub.[57] A roadmap was revealed in January 2024 that detailed the integration of ActivityPub in Threads.[58]
A faction of fediverse server admins, some of whom have listed their names under a pledge named "Fedipact", have expressed resistance to open federation with Threads over concerns that Meta would adopt an "embrace, extend, and extinguish" policy towards the network, or that Threads' moderation would fail to prevent the spread of abusive content targeted towards marginalized communities.[59][60][61]
In March 2024, Threads implemented a beta version of Fediverse support, allowing Threads users to view the number of Fediverse users that liked their post, and allowing Fediverse users to view posts from Threads on their own instances.[62][63][64] On April 2, the officialThreads account for PresidentJoe Biden enabled federation on its profile, making Biden the first President of the United States to have a presence on the Fediverse.[65] The ability to view replies from the Fediverse within Threads was added in August.[66]
In December 2023, the social magazine appFlipboard began integrating with the Fediverse by federating publisher accounts viaActivityPub. CEOMike McCue stated the move was intended to break away from "walled garden" ecosystems, making Flipboard content discoverable and interactive for users on platforms likeMastodon.[67]
During the2023 Reddit API controversy, the decentralized link aggregatorLemmy experienced a significant surge in growth as users sought alternatives toReddit.[68] The platform saw its monthly active user count rise from approximately 1,000 to over 66,000 within weeks of the protests, exacerbated by Reddit's decision to temporarily ban communities and users promoting the migration to Fediverse alternatives.[69]
GNU social – One of the earliest Fediverse projects, historically using theOStatus protocol to enable federation before the widespread adoption of ActivityPub.[75]
Diaspora – A decentralized social network that uses its own custom protocol.
^"Introducing Threads: A New Way to Share with Text". July 5, 2023. RetrievedDecember 25, 2023.Our vision is that people using compatible apps will be able to follow and interact with people on Threads without having a Threads account, and vice versa, ushering in a new era of diverse and interconnected networks.