Planck is a stand-alone ClojureScript REPL for macOS and Linux.
Planck launches instantly and is useful for scripting.

You can run Clojure-idiomatic scripts with Planck:
(require '[planck.core :refer [line-seq with-open]]
'[planck.io :as io]
'[planck.shell :as shell])
(with-open [rdr (io/reader "input.txt")]
(doseq [line (line-seq rdr)]
(println (count line))))
(shell/sh "say" "done")
Get it: On macOS brew install planck, on Ubuntu install using apt-get.
Read the Planck User Guide or browse the Planck SDK.
Planck is free and open source.