clojure verbose compiler output

(let [spacing (atom -1)]
  (alter-var-root #'clojure.core/load-one
                  (fn [old-fn]
                    (fn [lib need-ns require]
                      (let [s (swap! spacing inc)]
                        (println (str (apply str (take s
                                                       (repeat " ")))
                                      "Compiling") lib)
                        (old-fn lib need-ns require)
                        ;; (println "...finished" lib)
                        (swap! spacing dec))))))