This article is a part of CQK Top 10 series.

In the team that develops Allegro Recommendation Platform we weren’t happy with our integration tests. Long setup and assertions blocks resulted in a low signal—to—noise ratio and poor readability. These tests were also full of ad hoc variables like 1, ABC, OK or NOK, which caused that it was hard to find a connection between input and output data. Moreover, any change in an API caused changes in many tests.