What are durable functions?

Short answer: Durable Functions allow stateful workflows in serverless apps. Enable orchestration, chaining, and long-running tasks without managing state manually. Example: [FunctionName("OrchestratorFunction")] public static async Task RunOrchestrator( [OrchestrationTrigger] IDurableOrchestrationContext context) {

Example code

await context.CallActivityAsync("HelloActivity", "Tokyo");
await context.CallActivityAsync("HelloActivity", "Seattle");
}

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.