Cloudflare Durable Objects

Status: Production Ready ✅ Last Updated: 2025-11-25 Dependencies: cloudflare-worker-base (recommended) Latest Versions: wrangler@4.50.0+, @cloudflare/workers-types@4.20251125.0+ Official Docs: https://developers.cloudflare.com/durable-objects/

Table of Contents

What are Durable Objects? • Quick Start • When to Load References • Class Structure • State API • WebSocket Hibernation • Alarms • RPC vs HTTP • Stubs & Routing • Migrations • Common Patterns • Critical Rules • Known Issues

What are Durable Objects?

Globally unique, stateful objects with single-point coordination, strong consistency (ACID), WebSocket Hibernation (thousands of connections), SQLite storage (1GB), and alarms API.

Use for: Chat rooms, multiplayer games, rate limiting, session management, leader election, stateful workflows

Quick Start (10 Minutes)

Option 1: Scaffold New DO Project