Reintroducing Lexicon Community
If you build on AT Protocol, you've touched a lexicon. They're the schema files that give records their shape, and most of them live under vendor namespaces like app.bsky.*. That's fine for vendor products. It's less fine for the things everyone needs, like bookmarks or calendar events. Nobody should have to depend on one company's namespace to say "this is an RSVP."
That's what Lexicon Community is for. We steward community.lexicon.*: schemas that are collectively owned, MIT licensed, and governed in the open.
This blog is new, so a reintroduction is in order.
(Photo by Ashkan Forouzani on Unsplash)
Where we came from
We started in late 2024 with a drafted governance model and a belief that there are a lot of lexicons in the ATmosphere that should be collectively owned. Bookmarks merged that December after weeks of open discussion. Calendar events and locations landed in early 2025, then a general-purpose like record that March. The Technical Steering Committee grew to seven members along the way, including Bluesky PBC.
Today the namespace covers seven areas: app profiles and listings, bookmarks, calendar events and RSVPs, likes, locations (street addresses, coordinates, H3 cells, Foursquare POIs), Web Monetization, and AI-use preferences. Real applications use them in production. That was always the test. A shared schema is only worth having if people build on it.
None of it happened by itself. Bookmarks came from @western-red-cedar.bsky.social and the dozen people who worked through the discussion with them. The app namespace grew out of a community working group and @pixeline.be 's proposal. Location keeps drawing new design work, like @schuyler.info 's gazetteer place proposal. And a lot of other people weighed in on pull requests and forum threads along the way. Thank you.
What we are
A volunteer-run organization. Seven TSC members steward the namespace with a consent-based decision model, working groups do the design work, and anyone can contribute: schema design, docs, reference code, or an informed opinion on a proposal. We're not a company. We're also not in a hurry to fill the namespace. A lexicon earns its place by being used.
What's changing
We just finished a restructuring with some important changes to how we work.
The website is now the source of truth. The governance documents moved to lexicon.community: the governance model, the contributor covenant, and the contributing guide, each with its effective date and a changelog, so you can see how the rules have changed and not just what they say today. There's also a directory of every published schema. The old governance repository is being archived.
The schemas moved, too. The canonical repository is now tangled.org/lexicon.community/lexicons, with GitHub staying on as a mirror.
Resolution got its own identity. community.lexicon.* NSIDs resolve through @lexicons.lexicon.community, a dedicated repository that holds the published schema records and nothing else. If you build SDKs or services, one unauthenticated request fetches the whole schema set as a verifiable CAR file for offline use.
The process is written down now, and it's lighter than it was. Working groups are self-formed and anyone can start one. The TSC's job moved to the end of the process, where pull requests get approved once the work is done, and the acceptance bar is real-world use. Small improvements don't need any ceremony at all.
We meet monthly: first Thursday, 1:00 PM ET, scheduled as a community.lexicon.calendar.event record. Yes, we use our own lexicon for it.
And there's this blog. Long-form writing lands here, and every post gets a companion topic on our forum for discussion. The blog, the forum, and @lexicon.community are the official channels.
Get involved
The front door is the forum: discourse.atmosphere.community/c/lexicon-community. Bring the lexicon you wish existed, and bring the application that would use it. Several existing lexicons are looking for maintainers. If you build with location data, calendars, or bookmarks, come steward one.
Browse the lexicon schema directory and explore any of them on Lexicon Garden, read the governance model, follow @lexicon.community, and subscribe here.
