anchor.diff:  
     configurePhase = ''
       python waf configure --prefix=$out \
  -      ${optionalString (optDbus != null) "--dbus"} \
  +      --dbus \
         --classic \
  -      ${optionalString (optLibffado != null) "--firewire"} \
  -      ${optionalString (optAlsaLib != null) "--alsa"} \
  -      --autostart=${if (optDbus != null) then "dbus" else "classic"} \
  +      ${optionalString (!libOnly) "--firewire"} \
  +      ${optionalString (!libOnly) "--alsa"} \
  +      --autostart=dbus \
     '';
   
     buildPhase = ''
  
positive.code: { stdenv, fetchFromGitHub, pkgconfig, python, makeWrapper
  , bash, libsamplerate, libsndfile, readline, expat
  
  # Optional Dependencies
  , dbus ? null, pythonDBus ? null, libffado ? null, alsaLib ? null
  , libopus ? null
  
  # Extra options
  , prefix ? ""
  }:
  
  with stdenv;
  with stdenv.lib;
  let
    libOnly = prefix == "lib";
  
    optDbus = shouldUsePkg dbus;
    optPythonDBus = if libOnly then null else shouldUsePkg pythonDBus;
    optLibffado = if libOnly then null else shouldUsePkg libffado;
    optAlsaLib = if libOnly then null else shouldUsePkg alsaLib;
    optLibopus = shouldUsePkg libopus;
  in
  stdenv.mkDerivation rec {
    name = "${prefix}jack2-${version}";
  
negative.code:     sha256 = "1a2213l7x6sgqg2hq3yhnpvvvqyskhsmx8j3z0jgjsqwz9xa3wbr";
    };
  
    nativeBuildInputs = [ python makeWrapper ];
    buildInputs = [
      python
  
      libsamplerate libsndfile readline expat
  
      dbus libopus
    ] ++ optionals (!libOnly) [
      alsa-lib
      ffado_lib
      pythonPackages.dbus
    ];
  
    prePatch = ''
  