[LeonidasXIV]

For starters you'd need to have imperative control structures like `while`, `continue`, `break` and a `return` that basically returns from anywhere. That can probably be built with macros.

Then you would need to have ways to mutate variables, so you'd need to stop using Clojure's persistent collections and instead use the ones provided by the JVM.

Overall, you can do it if you want to, it is just somewhat painful to do so and the language will fight you. This is like my who tried to write functional Python which is possible but then it is just a much worse Clojure.