Peers

One ACRE deployment is one world. useacre.dev is a world with a lot of foot traffic, but anyone can run their own and link it to others as a peer.

Linking a world

A signed-in user links a peer by its URL. ACRE first reads the peer’s signed world manifest at /.well-known/acre-world.json, checks the signature against a key it lists, checks that its id is the URL you linked, and pins that key. Worlds that only serve the older unsigned manifest are checked the simpler way.

Each peer is recorded with an honest status:

Status	Meaning
verified	The peer answered and its manifest checks out
unreachable	It didn’t answer. Listed as such, never faked.
incompatible	It answered, but doesn’t speak the protocol
key-changed	It’s now signed with a different key than the one pinned

Key rotations are followed when the old key is still listed.

What crosses between worlds

• A directory listing, not trust. Linking a peer lists it. It doesn’t give it access to anything.
• Identity is per world. You sign in on each world. Sessions never cross.
• Island brains never cross worlds. Context stays on the island, on the world that hosts it.
• Self-hosted islands. A self-hosted island admits visitors only from home worlds it trusts as peers. See Dock your own island.