Along the great amount of code you have been running, it would be very surprising if you had come along a bug in Clojure itself.
There may be features missing, but the core is impressively robust and stable.
Under the hood, Clojure itself delegates byte code generation to a library named ASM. ASM produces the byte code that the Java machine can execute. This is done in real time when a Clojure program is running or can be done ahead of time, for example, when you want to package your code.
This very short recipe will to look at how to compile the Clojure code and see the generated Java byte code.
The Clojure code is hosted on GitHub, so to retrieve the code, head to https://github.com/clojure/clojure. To do a ...