# Durable Objects

A special kind of Cloudflare Worker combining compute with storage

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## Overview

- [Cloudflare Durable Objects](https://docs.ahq.lat/durable-objects/index.md): Build stateful serverless applications with Durable Objects, including AI agents, real-time chat, and collaborative apps.

## Getting started

- [Getting started](https://docs.ahq.lat/durable-objects/get-started/index.md): Create and deploy your first Durable Object with SQLite storage and a companion Worker.

## REST API

- [REST API](https://docs.ahq.lat/api/resources/durable_objects/subresources/namespaces/methods/list/index.md): Manage Durable Objects namespaces and objects using the Cloudflare REST API.

## Examples

- [Examples](https://docs.ahq.lat/durable-objects/examples/index.md): Code examples demonstrating common Durable Objects patterns, including counters, WebSockets, and alarms.
- [Agents](https://docs.ahq.lat/agents/index.md): Build AI-powered Agents on Cloudflare
- [Use the Alarms API](https://docs.ahq.lat/durable-objects/examples/alarms-api/index.md): Use the Durable Objects Alarms API to batch requests to a Durable Object.
- [Build a counter](https://docs.ahq.lat/durable-objects/examples/build-a-counter/index.md): Build a counter using Durable Objects and Workers with RPC methods.
- [Durable Object in-memory state](https://docs.ahq.lat/durable-objects/examples/durable-object-in-memory-state/index.md): Create a Durable Object that stores the last location it was accessed from in-memory.
- [Durable Object Time To Live](https://docs.ahq.lat/durable-objects/examples/durable-object-ttl/index.md): Use the Durable Objects Alarms API to implement a Time To Live (TTL) for Durable Object instances.
- [Use ReadableStream with Durable Object and Workers](https://docs.ahq.lat/durable-objects/examples/readable-stream/index.md): Stream ReadableStream from Durable Objects.
- [Use RpcTarget class to handle Durable Object metadata](https://docs.ahq.lat/durable-objects/examples/reference-do-name-using-init/index.md): Access the name from within a Durable Object using RpcTarget.
- [Testing Durable Objects](https://docs.ahq.lat/durable-objects/examples/testing-with-durable-objects/index.md): Write tests for Durable Objects using the Workers Vitest integration.
- [Use Workers KV from Durable Objects](https://docs.ahq.lat/durable-objects/examples/use-kv-from-durable-objects/index.md): Read and write to/from KV within a Durable Object
- [Build a WebSocket server with WebSocket Hibernation](https://docs.ahq.lat/durable-objects/examples/websocket-hibernation-server/index.md): Build a WebSocket server using WebSocket Hibernation on Durable Objects and Workers.
- [Build a WebSocket server](https://docs.ahq.lat/durable-objects/examples/websocket-server/index.md): Build a WebSocket server using Durable Objects and Workers.

## Tutorials

- [Tutorials](https://docs.ahq.lat/durable-objects/tutorials/index.md): Step-by-step Durable Objects tutorials for building real-world applications.
- [Build a seat booking app with SQLite in Durable Objects](https://docs.ahq.lat/durable-objects/tutorials/build-a-seat-booking-app/index.md): This tutorial shows you how to build a seat reservation app using Durable Objects.

## Demos and architectures

- [Demos and architectures](https://docs.ahq.lat/durable-objects/demos/index.md): Explore demo applications and reference architectures that use Durable Objects.

## Videos

- [Videos](https://docs.ahq.lat/durable-objects/video-tutorials/index.md): Watch video tutorials on building stateful applications with Durable Objects.

## Release notes

- [Release notes](https://docs.ahq.lat/durable-objects/release-notes/index.md): Track the latest changes, fixes, and new features for Durable Objects.

## api

- [Alarms](https://docs.ahq.lat/durable-objects/api/alarms/index.md): Schedule future wake-ups for Durable Objects using the Alarms API with guaranteed at-least-once execution.
- [Durable Object Base Class](https://docs.ahq.lat/durable-objects/api/base/index.md): API reference for the DurableObject abstract base class and its handler methods.
- [Durable Object Container](https://docs.ahq.lat/durable-objects/api/container/index.md): Access and manage containers associated with a Durable Object, including start, stop, and interaction methods.
- [Durable Object ID](https://docs.ahq.lat/durable-objects/api/id/index.md): API reference for DurableObjectId, the 64-digit hex identifier used to address a Durable Object.
- [KV-backed Durable Object Storage (Legacy)](https://docs.ahq.lat/durable-objects/api/legacy-kv-storage-api/index.md): API reference for the legacy KV-backed Durable Objects storage methods, including get, put, delete, and list.
- [Durable Object Namespace](https://docs.ahq.lat/durable-objects/api/namespace/index.md): API reference for DurableObjectNamespace, which creates IDs and obtains stubs to interact with Durable Objects.
- [SQLite-backed Durable Object Storage](https://docs.ahq.lat/durable-objects/api/sqlite-storage-api/index.md): API reference for SQLite-backed Durable Object storage, including the SQL API and key-value methods.
- [Durable Object State](https://docs.ahq.lat/durable-objects/api/state/index.md): API reference for DurableObjectState, which controls concurrency, WebSocket attachment, and storage access.
- [Durable Object Stub](https://docs.ahq.lat/durable-objects/api/stub/index.md): API reference for DurableObjectStub, the client used to invoke RPC methods on a remote Durable Object.
- [WebGPU](https://docs.ahq.lat/durable-objects/api/webgpu/index.md): Use the WebGPU API for GPU access from within Durable Objects in local development.

## best-practices

- [Access Durable Objects Storage](https://docs.ahq.lat/durable-objects/best-practices/access-durable-objects-storage/index.md): Read and write persistent data in Durable Objects using the Storage API, from within a Worker or externally.
- [Invoke methods](https://docs.ahq.lat/durable-objects/best-practices/create-durable-object-stubs-and-send-requests/index.md): Call RPC methods or send fetch requests to Durable Objects using stubs from a Worker.
- [Error handling](https://docs.ahq.lat/durable-objects/best-practices/error-handling/index.md): Handle exceptions from Durable Objects, including retryable and overloaded errors, with recommended patterns.
- [Rules of Durable Objects](https://docs.ahq.lat/durable-objects/best-practices/rules-of-durable-objects/index.md): Design guidelines for building correct and effective Durable Objects applications, covering when and how to use them.
- [Use WebSockets](https://docs.ahq.lat/durable-objects/best-practices/websockets/index.md): Serve WebSocket connections from Durable Objects, including the standard and Hibernation APIs.

## concepts

- [Lifecycle of a Durable Object](https://docs.ahq.lat/durable-objects/concepts/durable-object-lifecycle/index.md): Understand how a Durable Object is created, activated, handles requests, and is eventually evicted.
- [What are Durable Objects?](https://docs.ahq.lat/durable-objects/concepts/what-are-durable-objects/index.md): Durable Objects provide globally unique, single-threaded compute instances with persistent storage on Cloudflare.

## observability

- [Data Studio](https://docs.ahq.lat/durable-objects/observability/data-studio/index.md): View and edit SQLite-backed Durable Object storage data through the Cloudflare dashboard UI.
- [Metrics and analytics](https://docs.ahq.lat/durable-objects/observability/metrics-and-analytics/index.md): View Durable Objects namespace-level and request-level metrics, analytics, and logs via the Cloudflare dashboard or GraphQL API.
- [Troubleshooting](https://docs.ahq.lat/durable-objects/observability/troubleshooting/index.md): Debug Durable Objects with wrangler dev and wrangler tail, and resolve common errors like overload and storage issues.

## platform

- [Known issues](https://docs.ahq.lat/durable-objects/platform/known-issues/index.md): Known issues with Durable Objects, including global uniqueness guarantees, code updates, and development tool limitations.
- [Limits](https://docs.ahq.lat/durable-objects/platform/limits/index.md): Account, storage, CPU, and SQL limits for Durable Objects on Free and Workers Paid plans.
- [Pricing](https://docs.ahq.lat/durable-objects/platform/pricing/index.md): Durable Objects compute and storage billing, including pricing examples and free tier limits.
- [Choose a data or storage product](https://docs.ahq.lat/workers/platform/storage-options/index.md): Compare Cloudflare storage and data products to find the best option for your Durable Objects use case.

## reference

- [Data location](https://docs.ahq.lat/durable-objects/reference/data-location/index.md): Restrict Durable Objects to specific jurisdictions or provide location hints to control where data is stored and processed.
- [Data security](https://docs.ahq.lat/durable-objects/reference/data-security/index.md): Durable Objects data security properties including encryption at rest, encryption in transit, and compliance certifications.
- [Gradual Deployments](https://docs.ahq.lat/workers/configuration/versions-and-deployments/gradual-deployments/#gradual-deployments-for-durable-objectsindex.md): Gradually deploy changes to Durable Objects.
- [Durable Objects migrations](https://docs.ahq.lat/durable-objects/reference/durable-objects-migrations/index.md): Configure Wrangler migrations to create, rename, delete, or transfer Durable Object classes.
- [Environments](https://docs.ahq.lat/durable-objects/reference/environments/index.md): Configure Durable Object bindings across Wrangler environments for staging, production, and custom deployments.
- [FAQs](https://docs.ahq.lat/durable-objects/reference/faq/index.md): Frequently asked questions about Durable Objects pricing, limits, and metrics.
- [Glossary](https://docs.ahq.lat/durable-objects/reference/glossary/index.md): Definitions of key terms used in Cloudflare Durable Objects documentation.
- [In-memory state in a Durable Object](https://docs.ahq.lat/durable-objects/reference/in-memory-state/index.md): Store and access transient in-memory state within a Durable Object instance between requests.