Durable Objects

Cloudflare’s single-instance objects with their own storage: one place in the world that owns a piece of state.

Each object has a unique id, runs in one location at a time and processes requests one by one, so there are no races on its state. That makes it a natural fit for a chat room, a game lobby, a document being edited together, a counter or a budget that must never be overspent. Objects can hold WebSocket connections and wake up on alarms.

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Related terms

Edge computing (Workers): Running code in data centers close to the user, on the CDN, instead of in one central region.
Server-Sent Events (SSE): A standard way for a server to push a stream of updates to the browser over one long HTTP response.
Authoritative server (netcode): In multiplayer games, the server decides the true game state; clients only send inputs and predict what will happen.

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