Hi! Thanks for the excersises! You compare programmers to musicians and that makes me think about Hanon excersises. I think that coding Katas are pretty similar to these. The Hanon excersises are a set of 60 excersises for the piano to train some difficult fingering techniques. They are to be repeated daily to retain technique. They were created by Charles-Louis Hanon. Hanon excersises have received quite a lot of criticism. It includes "doing drills repeatedly will make your attitude towards music mechanical", "it's just boring", "even when you've mastered all 60 you still haven't performed one actual piece of music" etc. Now I'm not saying that's automatically true for code Katas but it would be interesting to hear your comments on some questions that come to mind: Why is it important to do these drills? What skills do they add to your repertoar? After doing all your Katas, will you be able to write good programs? Is coding Katas anything like Hanon excersises do you think? You say that musicians repeatedly practice but you should now that successful musicians also take great care practicing the right things. There is no end to the amount of time you can spend practicing things mindlessly. More on that in this book: http://www.pianofundamentals.com/ which has some interesting ideas about how to practice the piano. Wikipedia has an article about the Hanon excersises: http://en.wikipedia.org/wiki/The_Virtuoso_Pianist_in_60_Exercises I very much like to hear you elaborate on the Katas and how to use them properly, I find the subject very interesting.