I completely agree but in many cases, as opposed to a book, I don't know where to start. And in many cases you do need some domain knowledge or at least underst

I completely agree but in many cases, as opposed to a book, I don't know where to start. And in many cases you do need some domain knowledge or at least understand the requirements and mentally map code to what it's supposed to do. Reading code with its unit test I guess is the best way. Is there a good list of "must read" code that someone is curating that you recommend?