







A protocol engineer at the social-media platform Bluesky describes building an open protocol around a fast-growing social media platform.
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.

A Self-Authenticating Social Protocol - Bluesky
Bluesky’s mission is to drive the evolution from platforms to protocols. The conceptual framework we've adopted for meeting this objective is the "self-authenticating protocol."
FR#157 – Social Software Distribution
Open social protocols are expanding beyond social media into the infrastructure developers use to build, distribute, and discover software. Three recent launches show what that looks like in practice.

Blogging on the open social web - and more exciting features - pckt - Dev Journal
ATmosphere — referring to the growing ecosystem of applications built on the AT Protocol, a federated protocol for open social platforms. Not to be confused ...

AT Protocol
The AT Protocol is a protocol and set of open standards for decentralized publishing and distribution of self-authenticating data within the social web. It serves as the technical foundation of the Bluesky social network, originally developed as a reference implementation for the protocol, as well as an ecosystem of interoperable social applications and services collectively referred to as the ATmosphere.
FediForum | Growing the Open Social Web:<br>An Online Un-Workshop
Since the Twitter takeover by Elon Musk over three years ago, the Open Social Web has been adopted by an enthusiastic community. People world-wide are building and using open social platforms and open social protocols to better interact with others online.

Starting from scale in the design of the AT Protocol - Paul's Leaflets
Bluesky was founded in 2022 to produce a protocol which Twitter could adopt. The product goals changed, but the requirements didn't.
Open Graph protocol
The Open Graph protocol enables any web page to become a rich object in a social graph.

The AT Protocol's interesting design - LittleBit
Bluesky's backend was made to be more than a social network
Building your own algorithm on Bluesky and AT Protocol with Graze
Beyond Bluesky: These are the apps building social experiences on the AT Protocol | TechCrunch
A list of AT Protocol-based, consumer-facing apps that are either built on top of Bluesky or its underlying protocol, allowing users to take back control over their social networking experiences and personal data.

Bluesky Protocol Services
High scale open social, unlocked for every builder. Bluesky operates public infrastructure for the AT Protocol — Jetstream, Relay, and the Bluesky API — as open services anyone can build on.

Chad Kohalyk (@chadkoh@indieweb.social)
Web publishing is facing its next challenge: a new iteration of centralizing platforms. BUT there is also a new wave of open protocols and standards that can help us gain our independence. Next month in NYC we are gathering a group of frontier technologists and popular web publishers to discuss how we can sail into this next platform shift as captains. #ProtocolsForPublishers https://pfp.unternet.co
Another reason why it’s so important that we have open protocols for social media.
Kai Kupferschmidt
One of the issues that has come up again and again in my reporting on misinformation and social media is the massive influence social media companies have on research in the field. Last night a preprint dropped that tries to get at this with some numbers. My piece in @science.org (and 🧪🧵 coming):