Azure Functions
Azure Functions is Microsoft's serverless compute platform on Azure. It lets services run in response to triggers (HTTP requests, queue messages, blob events, timers, SFTP feeds, and more) without standing up and managing dedicated hosts. Functions are written in C# (or other supported languages), deployed independently of the rest of a system, and scale on demand inside the Azure platform.
Official WebsiteWhen to use Azure Functions
Use Azure Functions when work is genuinely event-driven or scheduled, when the workload is bursty or sporadic enough that paying for an always-on host is wasteful, and when a workload has a clean boundary that benefits from being deployed and scaled independently. They are a strong fit for ingestion adapters, scheduled jobs and integration glue between services, and they sit comfortably alongside Aspire-orchestrated services in a multi-service .NET system.
Why choose Azure Functions?
Functions earn their keep when the alternative is standing up an always-on service for a workload that runs for a few minutes a day. I use them for ingestion paths and scheduled jobs where the deployment unit is small, the trigger is naturally event-driven, and the operational model benefits from Azure managing the host. On a recent learner platform engagement, the OneFile ingestion path was an Azure Function that connected to an SFTP feed, parsed CSV exports and landed parsed records into the progress engine's store.