Building Multiplayer Applications with Cloudflare Workers & Durable Objects

Durable Objects in Cloudflare are a storage solution that allows state to be stored at the edge. They are designed for building scalable collaborative applications like document editors, game servers, and chat rooms. Durable Objects provide unique instances globally for handling state and coordination across multiple client requests.

Durable Objects are used with Cloudflare Workers to handle state and coordination in serverless environments. Workers can create and interact with instances of Durable Objects via an API, allowing state to be maintained across requests. Each Durable Object instance is uniquely addressable, ensuring consistent state management.

Cloudflare's Durable Objects are designed to be infinitely scalable by leveraging a unique global distribution model. They are hosted in multiple Cloudflare data centers worldwide, allowing them to handle a large number of requests and maintain high performance and availability.

The billing for Durable Objects is based on the wall clock time during which an object handles an active request. Once the Durable Object returns a response, billing stops, making it a cost-effective solution for applications that require intermittent coordination across global users.

Durable Objects are suitable for high traffic scenarios as long as the load is distributed across many instances. Each Durable Object handles a portion of the traffic, allowing the system to scale efficiently by distributing the workload.

One limitation is that each Durable Object instance runs a single thread of JavaScript, which may not be suitable for tasks requiring intense computation or very high concurrency. Additionally, accessing a Durable Object from far geographical locations may introduce latency.

Durable Objects are ideal for collaborative applications because they allow centralized coordination of state changes across multiple clients. This is essential for apps where users interact in real-time, such as in collaborative editing or multiplayer gaming, ensuring that all users see the same state.