In this half-day workshop, we’ll have a look at a number of tests we all could (and probably will) have written. First, we will perform a thorough code review on them, and then we’ll improve the code by applying fundamental object-oriented programming principles. As we go along, we’ll see our test code grow in readability and maintainability, while learning to recognize, apply and explain to other concepts like (de-)serialization, encapsulation, inheritance, polymorphism, abstraction and (some of) the SOLID principles. We’ll also discuss when and were not to apply these concepts, because like so many things in life, it’s all about finding the right balance.