Durable Functions packages, extensions, and SDKs overview

Durable Functions is available for all first-party Azure Functions languages, including .NET, Node.js, Python, Java, and PowerShell. This article helps you find the right package to install for your language and hosting model.

In this article, extension refers to the binary that runs inside the Azure Functions host and implements the Durable Task protocol. SDK refers to the language-specific library you call in your application code. For .NET, the extension and SDK are combined in a single NuGet package.

Quick reference

The following table lists the primary Durable Functions package for each supported language and hosting model:

The following sections provide more detail on each language, including alternative storage provider packages.

.NET in-process

Add the Microsoft.Azure.WebJobs.Extensions.DurableTask NuGet package to your .csproj file. This package (sometimes called the "WebJobs extension") contains both the Durable Functions extension and the .NET in-process SDK.

.NET isolated

Add the Microsoft.Azure.Functions.Worker.Extensions.DurableTask NuGet package to your .csproj file. This package (sometimes called the "worker extension") replaces the WebJobs extension used in the in-process model.

Node.js, Python, Java, and PowerShell

Non-.NET languages use extension bundles to manage the Durable Functions extension automatically. You only need to install the Durable Functions SDK for your language:

• Node.js (JavaScript / TypeScript): The durable-functions npm package.
• Python: The azure-functions-durable PyPI package.
• Java: The durabletask-azure-functions Maven package.
• PowerShell: The AzureFunctions.PowerShell.Durable.SDK module.

Storage providers

Durable Functions uses a storage provider to persist orchestration state, entity state, and internal messages. The recommended provider is Durable Task Scheduler, an Azure-managed backend that requires no additional packages—only configuration. To get started, see Configure Durable Functions with Durable Task Scheduler.

Alternative storage providers

If you need a different backend, the following "bring your own" (BYO) storage providers are also available. For .NET apps, add the corresponding package to your .csproj in addition to your primary Durable Functions package.

The following table lists the BYO storage provider packages for each .NET hosting model:

Non-.NET languages manage the extension through extension bundles, so no additional storage provider package is needed in your application project.

GitHub repositories

Durable Functions is developed as open-source software. To contribute, request features, or report bugs, use the repository for your language or component: