Just type `in 20m Have a pause and rest` (on MacOs) and in 20 minutes a reminder notification saying "Have a pause and rest" will appear

in.scala

//> using scala 3.4.2
//> using platform native
//> using packaging.output in
//> using nativeMode release-full
//> using nativeLto full
//> using nativeGc none

import scala.concurrent.duration.*

@main def main(durationString: String, text: String, others: String*): Unit =
    runDetach(parseDuration(durationString), (text :: others.toList).mkString(" ") )

def parseDuration(s:String): Duration =
    def parse(cs:Array[Char], acc: Long, duration: Duration): Duration = cs.headOption.fold(duration){
        case d if d.isDigit => parse(cs.tail, acc * 10 + d.asDigit, duration)
        case 'h' => parse(cs.tail, 0, duration + Duration(acc, HOURS))
        case 'm' => parse(cs.tail, 0, duration + Duration(acc, MINUTES))
        case 's' => parse(cs.tail, 0, duration + Duration(acc, SECONDS))
        case x => throw new Exception(s"Unrecognised token in duration $x")
    }

    parse(s.toCharArray(), 0L, Duration.Zero)

def runDetach(waitTime: Duration, message: String): Unit =
    val command = s"""osascript -e "display notification \\"$message\\" with title \\"Reminder\\"""""
    val processBuilder: ProcessBuilder = 
        new ProcessBuilder("sh", "-c", s"sleep ${waitTime.toSeconds} && $command")
    processBuilder.inheritIO()
    val process: Process = processBuilder.start()
    process.getInputStream().close()
    process.getOutputStream().close()
    process.getErrorStream().close()