CIDER
The Clojure Interactive Development Environment that Rocks for Emacs
... in Emacs Lisp, Common Lisp (with SLIME or Sly), Scheme (with Geiser), and Smalltalk. Programmers are expected to program in a very dynamic and incremental manner, constantly re-evaluating existing Clojure definitions and adding new ones to their running applications. You never stop/start a Clojure application while using CIDER - you’re constantly interacting with it and changing it.