ActivityPub is an open, decentralized social networking protocol based on's ActivityPump protocol.[1] It provides a client/server API for creating, updating, and deleting content, as well as a federated server-to-server API for delivering notifications and content.[2]

Communication protocol
Developer(s)World Wide Web Consortium
IntroductionJanuary 23, 2018 (2018-01-23)
Based onActivity Streams, JSON-LD

Project status Edit

ActivityPub is a standard for the Internet in the Social Web Networking Group of the World Wide Web Consortium (W3C). The standard was co-authored by Evan Prodromou,[3] creator of StatusNet (now known as GNU social). At an earlier stage, the name of the protocol was "ActivityPump", but it was felt that ActivityPub better indicated the cross-publishing purpose of the protocol. It is the most widely supported standard (by some margin) in the Fediverse.[citation needed]

In January 2018, the World Wide Web Consortium (W3C) published the ActivityPub standard as a Recommendation.[2] Lead author Christine Lemmer-Webber notes that the team predominantly identified as queer, which led to features that help users and administrators protect against "undesired interaction." She also notes that the team authoring ActivityPub had no corporate participation.[4]

The W3C Social Community Group organizes a yearly free conference called ActivityPub Conf about the future of ActivityPub.[5][6]

Former Diaspora community manager Sean Tilley wrote an article that suggests ActivityPub protocols may eventually provide a way to federate Internet platforms.[7]

Notable implementations Edit

Federated (server-to-server) protocol Edit

  • Friendica, social networking software; implemented ActivityPub in version 2019.01.[8]
  • Lemmy, software for running Reddit-style news aggregators and discussion forums. Any instance can use ActivityPub to interact with other forums and form a federated social network.[9]
  • Libervia (in beta as of 2022)[10]
  • Mastodon, social networking software; implemented ActivityPub in version 1.6 and released in September 2017. It is intended that ActivityPub offers more security for private messages than the previous OStatus protocol.[11][failed verification]
  •, a microblogging social network, added support for ActivityPub in 2018[12] and was enabled by default for new users in October 2022.[13]
  • Misskey, a federated self-hosted software for microblogging with special reaction and Markdown formatting, akin to Tumblr and Discord, mostly popular in Japan.
  • Mobilizon, a federated event organising server
  • Nextcloud, a federated file-hosting service.[14][15]
  • PeerTube, a federated video-streaming service.[11]
  • Pixelfed, a federated image-sharing service resembling Instagram.[16]
  • WordPress via a plug-in to post blogs from users.[17]

Expected or announced implementations Edit

Other support Edit

See also Edit

References Edit

  1. ^ "Sandstorm and the Social Web". 29 May 2016.
  2. ^ a b "W3C Recommendation 23 January 2018".
  3. ^ Jackson, Joab (28 April 2022). "Challenges of Creating a Decentralized, Open Source Twitter". The New Stack. Retrieved 29 November 2022.
  4. ^ Klemmens, Ben (2023-01-02). "Mastodon—and the pros and cons of moving beyond Big Tech gatekeepers". Ars Technica. Retrieved 2023-01-18.
  5. ^ "ActivityPub Conf 2020". Archived from the original on 2021-06-02. Retrieved 2020-08-01.
  6. ^ "ActivityPub Conf 2019".
  7. ^ Tilley, Sean (23 September 2017). "A quick guide to The Free Network".
  8. ^ "Friendica 2019.01 released". Retrieved 2019-01-24.
  9. ^ "Lemmy - ActivityPub for link aggregation". Retrieved 2023-06-05.
  10. ^ "Libervia progress note 2022-W45". November 2022.
  11. ^ a b "Server-Server - ActivityPub implementation reports". Retrieved 2019-01-02.
  12. ^ "ActivityPub for your blog". 14 November 2018. Retrieved 2022-12-23.
  13. ^ "Mastodon and ActivityPub". 8 March 2021. Retrieved 2022-12-23.
  14. ^ Wallen, Jack (22 January 2019). "Nextcloud Social is a promising collaborative feature". Tech Republic. Retrieved 3 July 2020.
  15. ^ Poortvliet, Jos (2022-10-28). "No need to trust Musk. We go federated with Nextcloud Social!". Nextcloud. Retrieved 2022-11-10.
  16. ^ Krasnoff, Barbara (August 2022). "Eight photo-centric social sites that are not Instagram". The Verge.
  17. ^ "ActivityPub for WordPress". Github. Retrieved 7 July 2023.
  18. ^ Perez, Sarah (2022-11-21). "Tumblr to add support for ActivityPub, the social protocol powering Mastodon and other apps". TechCrunch. Retrieved 2022-11-24.
  19. ^ "Meta may soon reveal Threads, its Twitter competitor built on ActivityPub". 9 June 2023.
  20. ^ "Support ActivityPub for merge requests (&11247) · Epics · · GitLab". GitLab. Retrieved 2023-08-26.
  21. ^ "First forgejo monthly update - December 2022". Retrieved 2023-08-29.
  22. ^ Perez, Sarah (23 May 2023). "Flipboard becomes first app to support Bluesky, Mastodon and Pixelfed all in one place". TechCrunch. Retrieved 7 July 2023.

Further reading Edit