{ name
, run ? null
, connectOut ? null
, connectIn ? null
, group ? null
, trivmix
, stdenv
, makeWrapper
, jack2
}:

let
  genRun = if ! isNull run then run else (
    "${derivRun}/bin/run.sh"
  );
  derivRun = stdenv.mkDerivation {
    name = "trivmix-run";
    src = builtins.toFile "run.sh" ''
      #!/bin/sh

      ${if ! isNull connectIn then "jack_connect ${connectIn} $1" else ""}
      ${if ! isNull connectOut then "jack_connect $2 ${connectOut}" else ""}
    '';
    unpackPhase = "cat";
    buildInputs = [ makeWrapper ];
    installPhase = ''
      mkdir -p $out/bin
      cp $src $out/bin/run.sh
      chmod 755 $out/bin/run.sh
      wrapProgram $out/bin/run.sh \
        --prefix PATH : ${jack2}/bin
    '';
  };
in rec {
  out = {
    wantedBy = [ "sound.target" ];
    requires = [ "jack.service" ];
    serviceConfig = {
      Type = "simple";
      ExecStart = ''${trivmix}/bin/trivmix --client ${name} --run ${genRun} --level /dev/shm/mix/${name}/level${if ! isNull group then " --dir /dev/shm/mix/${group}/level" else ""}'';
      User = "jack";
      Group = "audio";
    };
  };
}