A key pair is a public key and a secret key that signs; a communal namespace gives each subspace to its key holder, an owned namespace gives everything to the namespace key, with no list anywhere; Willow'25 decides by the key's lowest bit.

It is the first fork in designing a Willow app.

Meadowcap is Willow's permission system. It knows two kinds of building.

In a communal namespace, every room belongs to whoever holds its key. A key pair is a public key anyone can see, and a secret key only you hold. Only the secret key can make a signature the public key checks. The subspace id is a public key. Your signature proves the room is yours.

In an owned namespace, the building itself has a key. Its holder owns every room, and peers reject anything without that signature. There is no list.

Which kind is a given namespace? The id says so. In Willow twenty five, the last bit of the key decides.

Rooms with their own keys, for a club where everyone keeps their own notes. One key over the door, for a group where one party decides who writes.

Check yourself. In a communal namespace, what proves a room is yours?