Note: you need to install Boot before trying this example out. See the Installation and Setup section if you haven't installed it yet.

Boot allows making executable Clojure files using shebang (#!) line. Place the following text into a file of your choice (this example assumes it's in the "current working directory" and is named hello.clj).

#!/usr/bin/env boot

(defn -main [& args]
  (println "Hello, world!"))

Then mark it as executable (if applicable, typically by running chmod +x hello.clj).
...and run it (./hello.clj).

The program should output "Hello, world!" and finish.