Clojure shutdown hook

shutdown-hook.clj

(ns myapp.shutdown-hook
  (:gen-class))

(defn add-shutdown-hook!
  "Adds a shutdown hook that executes the given function when the JVM is shutting down.
  
   Parameters:
   - f - function to execute on shutdown

   Returns nil."
  [f]
  (.addShutdownHook (Runtime/getRuntime) (Thread. ^Runnable f)))

;; Usage
(defn -main [& _]
  (add-shutdown-hook!
   (fn []
     (println "Shutting down cleanly...")))
  (println "Application running. Press Ctrl+C to stop.")
  (Thread/sleep 99999999)) ; simulate long-running app