New year, new episode. Mykola Gurov is the first guest of the year, and we challenge him with the heuristic “Diagnose before cure” from the Xebia Essentials repository. Mykola shares his opinion about observability and the importance to challenge our assumptions and bias. Focus on the purpose of the software rather than the technical details. We discuss testing in production, the different techniques to be effective, reduce the feedback cycle, and do it safely.