I gave a talk on tools.decompiler at Clojure/Conj in October 2017. Video here

Dependencies:

Leiningen:

[bronsa/tools.decompiler "0.1.0-alpha1"]

Usage:

Use lein javac to AOT compile clojure.tools.decompiler.RetrieveClasses then you can use lein repl or clj to launch a repl

Use decompile-classfiles to decompile AOT compiled classes:

user=> (require '[clojure.tools.decompiler :as d])
nil
user=> (d/decompile-classfiles {:input-path "path/to/root/classes/directory" :output-path "path/to/src"})
;; with no :output-path, decompile to stdout
[...]

You can use decompile-classes to decompile in memory classes, but to do so you must start the JVM using the java agent provided with tools.decompiler (use e.g. lein jar to build the jar):

[~/src/tools.decompiler] clj -J-javaagent:tools.decompiler.jar
user=> (require '[clojure.tools.decompiler :as d])
nil
user=> (defn foo [a] a)
#'user/foo
user=> (decompile-classes {:classes #{"user$foo"}}) ;; optionally :output-path to decompile to disk
Decompiling user$foo
(fn foo
  ([a] a)
nil