"... if I knew this a year ago I would did it better" This is a typical reaction when you learn something new and you are automatically applying it on stuff you did in past. The crucial question is: Should I go back and make it better or just let it go like it is? In software engineering it is question about refactoring. Honestly I prefer to do refactoring because I believe that " make things better " is a role of engineering in general. But on the other hand I am also lazy, older guys are telling me: " do not touch it if it works " and I really need to see a value of such a work. Therefore I have to somehow measure and visualize source code. This could be done by static code analyze, test coverage and performance tools. From the results I can Learn if my Refactor really made things Measurable better or not.