User guides
Two audiences use Acorn day to day: stewards running a community (covered in the steward guides) and the people joining one. This section is for the second group — share it with anyone who wants to know "how do I actually get in?" or is new to Blacksky and/or AT Protocol.
What is Blacksky?
Blacksky is an open-source, community-driven social network. Its mission is to give communities real tools for safety, governance, and control over their own spaces, instead of leaving those decisions to a corporate platform. Blacksky runs its own network of services, including the Blacksky app and Acorn — the offering that makes that infrastructure available to other communities, on any of Acorn's five plans.
What is AT Protocol?
AT Protocol (the "Authenticated Transfer Protocol") is the open network Blacksky, Bluesky, and a growing set of other apps and communities are built on — a bit like switching phone carriers while keeping your number and contacts. Your identity, posts, and social graph live on a personal data server (PDS) — Blacksky's shared PDS, a community's own dedicated PDS, or one you run yourself — and can move to a different provider without you losing anything.
Joining, by account type
| If your account is on… | You can… |
|---|---|
| Blacksky-hosted infrastructure (app or web) | Get full access: public feeds, community-only (permissioned) feeds and discussions, everything the space offers. |
| Bluesky, Northsky, Eurosky, or another AT Protocol app (e.g. mu.social) | Follow public feeds and join public discussions right away. Community-only spaces need migrating to Blacksky-hosted infrastructure to access — doable anytime, without losing posts or follows. |
| Nowhere yet — new to AT Protocol | Create a Blacksky-hosted account (below) and get full access from the start. |
How to join Blacksky
On the web:
- Go to blacksky.community → Create an Account.
- Enter your email, password, and birthdate (if applicable).
- Choose a username and domain — myatproto.social is open to anyone; domains like blacksky.app, afrolatinsky.app, and latinsky.app are reserved for their specific communities (Black and Latine).
- Add a profile picture, interests, and follow suggested accounts.
- Use your invitation link, or ask the community's steward to add you.
On mobile (public beta): Download the app for iOS or Android.
Already on AT Protocol? Follow a community's public feeds right away with your existing handle — no migration needed. To reach permissioned feeds, migrate to Blacksky-hosted infrastructure at move.blacksky.community — keeps your posts, follows, and identity intact, takes about a minute.
After you join
- Read the community's guidelines, if posted.
- Explore your default feeds, and look for others worth following.
- Introduce yourself, if that's the norm there.
- Reach out to a steward or moderator with questions about the space itself.
Getting help
Account/app issues (login trouble, crashes) → support@blacksky.app (include device type, OS version, a screenshot).
Questions about a specific community — its guidelines, feeds, how to get involved — ask your community's stewards for more information.