Clojure has a type system... but I know what you mean. Perhaps you could expense a copy of Martin Fowler's new 2nd edition of Refactoring? It uses JavaScript, so applying the lessons to Clojure will be even easier. Refactoring in dynamic languages just isn't an obstacle for some of us, I don't know why, but that book is the only thing I can think of that might help someone having trouble bridge the gap.