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In both cases, you need to launch a Clojure subprocess. This is most commonly done using a tool such as Leiningen.
SLIME and Swank Clojure
Once Leiningen is installed, run lein plugin install swank-clojure 1.3.4
Invoke M-x clojure-jack-in once Leiningen is installed to begin a Slime session for the current project.
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