Fitness functions are an essential part of evolutionary architectures. But how do they look like in practice? What kinds of fitness do they check and assert? And can you leverage fitness functions in your architecture, that maybe you deem not even evolutionary?

After a brief introduction we'll do a deep dive into some concrete examples, covering use cases for common architectural styles. We'll see examples in Java code (yes, code!), based on ArchUnit and jMolecules. But the basic ideas and concepts are applicable to other languages and technologies as well. Don't be afraid of the code – the simple examples are more about general structure and not about code details. There'll be accompanying, easy to understand diagrams for each example. This way, you'll get tangible, practical insights into fitness functions.

The session closes with a short discussion about when and where to write fitness functions and who should write them. And we'll see why this enables agility and continuous thinking about architecture in your software development teams. All these aspects will be easier to grasp once you've seen concrete examples.