Building Serverless Applications on Knative

Chapter 1. What Is Serverless, Anyway?

Serverless has been hyped as a transformational technology, leveraged as a brand by various development platforms, and slapped as a label on dozens of services by the major cloud providers. It promises the ability to ship code many times per day, prototype new applications with a few dozen lines of code, and scale to the largest application problems. It’s also been successfully used for production applications by companies from Snap (the main Snapchat app) to iRobot (handling communications from hundreds of thousands of home appliances) and Microsoft (a wide variety of websites and portals).

As mentioned in the Preface, the term “serverless” has been applied not only to compute infrastructure services, but also to storage, messaging, and other systems. Definitions help explain what serverless is and isn’t. Because this book is focused on how to build applications using serverless infrastructure, many chapters concentrate on how to design and program the computing layers. Our definition, however, should also shine a light for infrastructure teams who are thinking about building noncompute serverless abstractions. To that end, I’m going to use the following definition of serverless:

Serverless is a pattern of designing and running distributed applications that breaks load into independent units of work and then schedules and executes that work automatically on an automatically scaled number of instances.

In general,¹ the serverless pattern ...