There is no map here, no stored list of rooms, and no server holding a layout to send when someone arrives. Every room is produced at the moment it is needed, derived from the exact sequence of choices that led to it, and released as soon as it leaves the screen. The space is not large in the way a large building is large. It is unbounded, which is a different property. A large space has an edge somewhere in it that could in principle be reached, and this one does not have one to look for.

Each room derives from the room before it, combined with whichever exit was taken to leave it. The derivation is deterministic, so an identical sequence of choices always produces an identical room, with the same identifier, the same description, the same drawing, and the same four exits. Two people walking the same path see the same thing without anything passing between them, because neither one is reading a record. Both are running the same function against the same input. That consistency is the only sense in which any of this is real, and it does everything storage would ordinarily do.

The column on the left is the space itself. It shows the room currently occupied and the four ways out of it, and it changes as those exits are taken. Nothing about the route is recorded, and nothing about it survives a refresh. The column on the right draws the path so far, and it is the only account of a session that exists anywhere.

Leaving a room destroys it. Going back returns to the previous room, but the room just left is removed for the rest of the session, and the exit that led there is replaced with one derived fresh, pointing somewhere else. Everything that hung below it becomes unreachable at the same time. The path runs forward, and stepping backward costs whatever was on the branch behind. This is the only rule the space enforces, and it is enforced against the visitor rather than on their behalf.

The remaining pages describe the rest. Docs covers the structure in full, proof shows the code that produces it, and the appendix records what none of it establishes.