ActivityPub

About

ActivityPub (AP) is an internet federation protocol. It became the primary federation protocol for Mastodon starting with approximately version 2, which previously had been based on OStatus.

AP became a W3C recommendation on 2018-01-23, due in large part to the popularity of Mastodon.

Software

These primarily use AP:

• Calckey code
  • 2023-01-06 If you’re feeling adventurous, try out a CalcKey instance. Confusing at first, but way more features than Mastodon.
• GoToSocial
• Mastodon
• Misskey
• Pleroma
• Akkoma
• Takahē official

These support AP but primarily use another federation protocol:

• Hubzilla is based on the Zot protocol
• Friendica

Links

Reference

• Wikipedia (article created 2017-08-18)
• W3C
• ActivityPub.rocks - sort of a publicity site

History

• 2022-11-08 Christine Lemmer-Webber on octodon.social (toot.cat, archive.ph): «A lot of people contributed to ActivityPub, but I'm going to give a breakdown of the authors and what they did:»

News

• 2024/11/22 11:00 Etc/UTC [L..T] How decentralized is Bluesky really? «Since I worked on ActivityPub which connects together Mastodon, Sharkey, Peertube, GotoSocial, etc, etc, etc in the present-day fediverse, I often get asked whether or not I have opinions about ATProto vs ActivityPub, and the answer is that I do have opinions, but I am usually head-down focused on building what I hope to be the next generation of decentralized (social) networking tech, and so I keep to myself about such things except in private channels.» ... «But recently I have received some direct encouragement from a core Bluesky developer that they have found my writings insightful and useful and would be happy to see me write on the subject. So here are my thoughts.»

Commentary

• 2022-11-24 weirder.earth/@noracodes «it's great to see that we have so many ActivityPub server implementations in different languages/ecosystems:» A short list follows; discussion in thread.
• 2018-06-23 How to implement a basic ActivityPub server by Eugen Rochko
• 2017-08-11 A lot of folks have rightly questioned why I'm so hot and cold on ActivityPub.

Code

• Kroeg, an ActivityPub server written in C#
• landrok/ActivityPub: ActivityPub library in PHP