The Durable Functions extension in Azure Functions is now available. Durable Functions is used to build long-running, stateful function orchestrations in code using C# in a serverless environment. This will allow developers to implement many new scenarios not previously possible, including complex chaining scenarios, fan in/fan out patterns, stateful actors, and scenarios with long callbacks.
This feature has widely been acknowledged as a differentiator for Azure Functions, and isn't available in any of the competing serverless FaaS services.
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