Microsoft’s Event Grid is an important addition to Microsoft’s serverless options, providing the back end needed to build distributed applications that can work at scale, with minimal management and orchestration. It brings to Microsoft’s serverless tools an event routing fabric that simplifies subscribing to events raised by other Azure services and by external sources.
There’s a lot to be said for using serverless computing models as the basis of a modern cloud application architecture. For one thing, there’s no need to worry about the underlying infrastructure, or even the network you’re using, reducing the management load on your application orchestration tools. But serverless models, like Microsoft’s Azure Functions, are themselves limited, launching on demand in response to events. If they don’t receive the appropriate signals, they don’t fire.