How it works. The kill list lives at neighborhoods/<building>/invites.json. The invitation gate reads it online, before any join settles: a ticket on this list cannot join — instant, from the moment the file ships. Every other ticket in the building is untouched; that's the point of the one-line kill. This desk only drafts — it never writes to the site. You save, commit, and deploy, and the kill lands when the file ships, exactly like a paper book getting a line crossed out. To undo, take the line back out. Nothing is ever rotated; nobody else re-keys.