Simple Midi example for Clojure

miditest.clj

;; Adapted from https://stackoverflow.com/a/36466737/202538
;; Run with `clj -M miditest.clj`

(ns miditest
  (:import (javax.sound.midi 
            Synthesizer 
            MidiSystem 
            Instrument 
            MidiChannel 
            MidiUnavailableException)))

(let [midi-synth (MidiSystem/getSynthesizer)
        _ (.open midi-synth)
        instruments (.getInstruments (.getDefaultSoundbank midi-synth))
        midi-channels (.getChannels midi-synth)]
        
    (.loadInstrument midi-synth (first instruments))
    (.noteOn (first midi-channels) 60 100)
    (Thread/sleep 1000)
    (.noteOff (first midi-channels) 60))