What is inside the middle of the pyramid?

In the 2D models of the test pyramid, this section is generally reserved for “integration” testing, though it could also be used for service testing, system testing, contract testing, API testing, and so on. We can argue that a 3D test pyramid model is especially needed at this level, where many different test types are considered.

In this book, we are going to consider the middle of the test pyramid as the part that contains most of the backend-related testing of an application. I am also including performance testing as a hidden side of this level of the test pyramid.

As we build applications with different evolutions of the server-client architecture, we put more focus on the cloud. Careful testing becomes important here to make sure everything goes smoothly and to quickly and easily identify where exactly the problems are.

I remember once encountering a problem that was caused by a server in a bad state. This problem...