anchor.diff:  , pkg-config
   , cmake
   , zlib
  -, fetchpatch
   , dbus
   , networkmanager
  -, spidermonkey_60
  +, spidermonkey_68
   , pcre
   , gsettings-desktop-schemas
   , glib
  
positive.code: 
  stdenv.mkDerivation rec {
    pname = "libproxy";
    version = "0.4.15";
  
    src = fetchFromGitHub {
      owner = "libproxy";
      repo = "libproxy";
      rev = version;
      sha256 = "10swd3x576pinx33iwsbd4h15fbh2snmfxzcmab4c56nb08qlbrs";
    };
  
    outputs = [ "out" "dev" "py3" ];
  
negative.code:     JavaScriptCore
    ] else [
      glib
      spidermonkey_68
      dbus
      networkmanager
    ]);
  