anchor.diff:  
     system-config-printer = callPackage ../tools/misc/system-config-printer {
       libxml2 = libxml2Python;
  +    pythonPackages = python3Packages;
      };
   
     sitecopy = callPackage ../tools/networking/sitecopy { };
  
positive.code: 
    webfs = callPackage ../servers/http/webfs { };
  
    wikicurses = callPackage ../applications/misc/wikicurses {};
  
    wineMinimal = callPackage ../misc/emulators/wine {
      wineRelease = config.wine.release or "stable";
  
negative.code: 
    blender = callPackage  ../applications/misc/blender {
      cudatoolkit = cudatoolkit75;
      python = python35;
    };
  
    bluefish = callPackage ../applications/editors/bluefish {
  