[filoeleven]

I doubt there’s a guide anywhere: it’s far from a trivial undertaking. If you want to look at the Java code that builds all the primitives, see the Clojure/Lang folder:

https://github.com/clojure/clojure/tree/master/src/jvm/cloju...

Part of what makes it Clojure instead of just a Java-based lisp are the persistent data structures that allow for efficient immutability, and the seq interface for working with collections smoothly. There’s a big (scary, to my eyes) set of classes that underlies all of the convenience. Thankfully it’s very stable so I don’t have to think about it.