The AT Protocol

Bluesky was created to build a social protocol. In the spring, we released “ADX,” the very first iteration of the protocol. Over the summer we improved and simplified ADX’s design, and today we’re sharing a preview of what’s to come.

ADX is now the “Authenticated Transfer Protocol” — or, more simply, the “AT Protocol.”

A protocol for social networking

The “AT Protocol” is a new federated social network. It integrates ideas from the latest decentralized technologies into a simple, fast, and open network.

What’s a “federated” network? It’s a way for servers to communicate with each other — like email. Instead of one site running the network, you can have many sites. It means you get a choice of provider, and individuals and businesses can self-host if they want.

What makes AT Protocol unique:

Account portability. A person’s online identity should not be owned by corporations with no accountability to their users. With the AT Protocol, you can move your account from one provider to another without losing any of your data or social graph.

Algorithmic choice. Algorithms dictate what we see and who we can reach. We must have control over our algorithms if we're going to trust in our online spaces. The AT Protocol includes an open algorithms mode so users have more control over their experience.

Interoperation. The world needs a diverse market of connected services to ensure healthy competition. Interoperation needs to feel like second nature to the Web. The AT Protocol includes a schema-based interoperation framework called Lexicon to help solve coordination challenges.

Performance. A lot of novel protocols throw performance out of the window, resulting in long loading times before you can see your timeline. We don’t see performance as optional, so we’ve made it a priority to build for fast loading at large scales.

Up now: atproto.com

Since May, we’ve been doing protocol work in a public repository on GitHub, but we’ve mostly been quiet on our blog and Twitter.

This is starting to change: as of today, there’s an AT Protocol website. It’s not completely finished — you’ll find a few “TODOs” in the specs — but the technology is stable enough that we can start to communicate what we’re doing now.

Coming soon: the Bluesky app

The World-Wide Web wouldn’t have been much fun if it was created without a browser, and the same is true of the AT Protocol. So we’re also building a social app called Bluesky.

The word “Bluesky” evokes a wide-open space of possibility. It was the original name for this project before it took shape, and continues to be the name of our company. We’re calling the application we’re building Bluesky because it will be a portal to the world of possibility on top of the AT Protocol.

We’re looking forward to sharing more about the Bluesky application as it develops.

Initiate testing sequence

The next step is to start testing the protocol. Distributed protocol development is a tricky process. It requires coordination from many parties once a network is deployed, so we’re going to start in private beta to iron out issues. As we beta test, we’ll continue to iterate on the protocol specs and share details about how it works. When it’s ready, we’ll move to the open beta.

If you’re interested in participating in the private beta, sign up for the waitlist on the Bluesky website.

And if you’re interested in joining the team, we’re hiring a mobile developer to help build the Bluesky app. Check out our open position here.