Plenty of libraries allow you to write tests, but not all of them are equal. When tests pass you'll hardly see any differences. But when tests fail, your choice of a library can help or hinder troubleshooting.

In this talk we'll explore AssertJ, and the fluent assertions API it provides. We'll contrast this to alternatives like JUnit and Hamcrest, and show how subtle differences improve the experience.

We will also look at optimizing your usage of AssertJ, to get more meaningful error messages. Finally, a quick OpenRewrite recipe helps apply all these best practices at once.