I wrote these today: http://github.com/kch/macruby-programming-cocoa I strived for very idiomatic ruby. This code is 100% Objective-C-isms-free. • Each exercise has its own branch • Each commit in the branch is one completed stage in the book • Each commit message mentions the chapter for the project at that stage • Each commit message is also annotated with the path to the roughly equivalent Cocoa solution in Hillegass's tarball This is incomplete. I went up to chapter 9. I don't know when / if I'll do the rest. In addition to the exercises, a few challenges are done too.