My motivation for this talk is my own expierence as a freelancer and trainer. I have seen a lot of good and bad code in different places. As a freelancer I often had to deal with different, unknown and often large codebases. This talk tries not only to show examples of bad code, but also to analyze why it exists in the first place, and how to deal with it or fix it. I'll visit anti-patterns, but this talk is not about anti-patterns, as that would only spotlight one of the many problems.