







Many people are talking about decentralized social media protocols like #ActivityPub and #ATProto and all the amazing things one can do with them. But do you actually know how they work? We thought we'd do something about this. Come to #FediForum next week if you are curious and like to find […]
Original post on mastodon.social
mastodon.socialApr 20, 2026 at 5:42 PM
Seeing the Politics of Decentralized Social Media Protocols
Calls to decentralize feed-based social media have been driven by concerns about the concentrated power of centralized platforms and their societal impact. In response, numerous decentralized social media protocols have emerged, each interpreting “decentralization” in a different way. We analyze four such protocols (ActivityPub, AT Protocol, Nostr, and Farcaster) drawing on protocol documentation, media coverage, direct usage, and semi-structured interviews with protocol developers and experts to situate each protocol within its socio-technical goals. To support this analysis, we develop a grounded lexicon that facilitates the description and comparison of analogous components across each protocol. With it, we show how each protocol distributes control over key components differently, shaping who holds power over critical aspects such as user identity, curation, and infrastructural ownership. By examining protocols as socio-technical artifacts, we show how they prioritize different values and make distinct trade-offs, providing CSCW researchers with a lens to more effectively evaluate and design future decentralized social media systems.

atproto academy
Your resource for learning the decentralized social networking protocol powering the future of social media.
A conceptual model of ATProto and ActivityPub
If you were to design an open social networking protocol, what would that look like? Which metaphors and comparisons would you use to get a general idea of how the network functions? And what would you answer if people ask if your network is decentralised and federated?

Bluesky and the AT Protocol: Usable Decentralized Social Media
Bluesky is a new social network built upon the AT Protocol, a decentralized foundation for public social media. It was launched in private beta in February 2023, and has grown to over 10 million registered users by October 2024. In this paper we introduce the architecture of Bluesky and the AT Protocol, and explain how the technical design of Bluesky is informed by our goals: to enable decentralization by having multiple interoperable providers for every part of the system; to make it easy for users to switch providers; to give users agency over the content they see; and to provide a simple user experience that does not burden users with complexity arising from the system's decentralized nature. The system's openness allows anybody to contribute to content moderation and community management, and we invite the research community to use Bluesky as a dataset and testing ground for new approaches in social media moderation.

ActivityPub
ActivityPub is a protocol and open standard for decentralized social networking. It provides a client-to-server (C2S) API for creating and modifying content, as well as a federated server-to-server (S2S) protocol for delivering notifications and content to other servers. ActivityPub is the defining standard of the Fediverse, a decentralised social network of various social interaction models, and content types, which consists of independently managed instances of software such as Mastodon, Pixelfed and PeerTube, among others.
Recently I’ve been thinking about a couple of... - Adam Wood
Recently I’ve been thinking about a couple of different tech-related things that sort of overlap. One is the (emerging) shape of the new social web; the other is a pull I’m feeling to try and lessen reliance on American companies. I’ve been interested in / concerned by what became of social media for some time.1 Since the sundering of Twitter in 2022, I’ve kept an eye on the various alternatives, with particular interest in Mastodon and Bluesky. Actually, to be more accurate, my interest has been in the protocols behind those platforms: ActivityPub and AT Protocol respectively. Both have their...

ActivityPub
The ActivityPub protocol is a decentralized social networking protocol based upon the [ActivityStreams] 2.0 data format. It provides a client to server API for creating, updating and deleting content, as well as a federated server to server API for delivering notifications and content.
ActivityPub
The ActivityPub protocol is a decentralized social networking protocol based upon the [ActivityStreams] 2.0 data format. It provides a client to server API for creating, updating and deleting content, as well as a federated server to server API for delivering notifications and content.
Social Networking Utopia — Matt
In discussing the network topology of social networks — whether centralized like Facebook or federated like ActivityPub — I think the ult...

How decentralized is Bluesky really? -- Dustycloud Brainstorms
Recently due to various events (namely a lot of people getting off of X-Twitter), Bluesky has become a lot more popular, and excitement for its underlying protocol, ATProto, is growing. 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.
FediForum Talk: How To Bullshit Your Way Through a Conversation about ActivityPub
By Evan Prodromou, Social Web Foundation and editor of the ActivityPub standard. One of the best bluffers in the field of distributed social networks gives you just enough knowledge about ActivityP...
bnewbold.net
Bluesky released early documentation for the "AT Protocol" (atproto) a few weeks ago, and I've been noodling around with it. Technically, it strikes an appealing balance between rigid cryptographically signed content-addressable storage on the one hand, and familiar web-friendly schemas and integrations on the other. But at an ecosystem level, there are already a bunch of existing open social media projects. Does atproto bring anything interesting to the table? How might it fit in compared to other similar protocols?
We're so excited to support @thisismissem.social's work bringing FedCM to the open social web! atproto.com/blog/working-to-decentralize-…
Working to Decentralize FedCM - AT Protocol
atproto.com