PartyKit

Overview

PartyKit makes it simple to build multiplayer and real-time applications — collaborative editors, live cursors, chat, presence, and games — without running your own WebSocket infrastructure. You write a small server (“party”) that reacts to connections and messages, and PartyKit handles scaling, state, and deployment.

PartyKit joined Cloudflare and is built on Durable Objects. Active development of the Workers-native successor libraries (such as PartyServer) now happens in the cloudflare/partykit repository, while this repository hosts the original PartyKit platform, CLI, and documentation.

Key Features

• Real-time by default: WebSocket connections with rooms, broadcasts, and per-room state
• Add multiplayer with very little code to an existing app
• Stateful rooms backed by Durable Objects, so each room keeps its own memory and storage
• Local dev server and one-command deploys
• Integrations with popular collaboration tools such as Yjs for CRDT-based editing
• Extensive docs, guides, and examples for chat, cursors, games, and AI use cases

Getting Started

Requires Node.js 17 or newer. Create a new project with a server and a client:

npm create partykit@latest

Or add PartyKit to an existing project:

npx partykit@latest init

Then run the dev server and deploy when ready:

npm run dev
npm run deploy

Use Cases

• Collaborative documents and whiteboards
• Live cursors, presence, and reactions
• Chat rooms and notifications
• Multiplayer browser games
• Real-time dashboards and AI agents that stream updates to many clients

License

MIT License.