anchor.diff:  
   stdenv.mkDerivation rec {
     name = "guitarix-${version}";
  -  version = "0.33.0";
  +  version = "0.34.0";
   
     src = fetchurl {
       url = "mirror://sourceforge/guitarix/guitarix2-${version}.tar.bz2";
  -    sha256 = "1w6dg2n0alfjsx1iy6s53783invygwxk11p1i65cc3nq3zlidcgx";
  +    sha256 = "0pamaq8iybsaglq6y1m1rlmz4wgbs2r6m24bj7x4fwg4grjvzjl8";
     };
   
     nativeBuildInputs = [ gettext intltool pkgconfig python ];
  
positive.code:   buildInputs = [
      avahi bluez boost eigen fftw glib glibmm gtk gtkmm libjack2
      ladspaH librdf libsndfile lilv lv2 serd sord sratom
      zita-convolver zita-resampler
    ];
  
    configureFlags = [
  
negative.code: { stdenv, fetchurl, gettext, intltool, pkgconfig, python
  , avahi, bluez, boost, eigen, fftw, glib, glibmm, gtk, gtkmm, libjack2
  , ladspaH, librdf, libsndfile, lilv, lv2, serd, sord, sratom
  , webkitgtk2, zita-convolver, zita-resampler
  , optimizationSupport ? false # Enable support for native CPU extensions
  }:
  
  