anchor.diff:  
     mcabber = callPackage ../applications/networking/instant-messengers/mcabber { };
   
  -  mcron = callPackage ../tools/system/mcron { };
  +  mcron = callPackage ../tools/system/mcron {
  +    guile = guile_1_8;
  +  };
   
     mdbtools = callPackage ../tools/misc/mdbtools { };
   
  
positive.code:   drgeo = builderDefsPackage (import ../applications/science/geometry/drgeo) {
      inherit (gnome) libglade gtk;
      inherit libxml2 guile perl intltool libtool pkgconfig;
    };
  
    tetgen = callPackage ../applications/science/geometry/tetgen { };
  
negative.code: 
    trackballs = callPackage ../games/trackballs {
      debug = false;
      guile = guile_1_8;
    };
  
    tunctl = callPackage ../os-specific/linux/tunctl { };
  