Azure Functions is a popular way to handle event-driven process without the need to think about how to connect input/output data, how to trigger action on a specific event (like the input of a data) and how to manage the infrastructure that will host application. With Azure Functions, Developers can focus on what is important, and that is coding. In this blog post, we will show how to create a simple image processing application where we upload to cloud data storage a picture that will trigger logic that will process the picture and return to the storage resized image with round corners and some additional logo. We will create and debug Azure Function on macOS (but you can follow the example on any platform), data will be stored on Azure Storage and the final product will be hosted on Azure inside of a Function App.