anchor.diff:    stdenvCross = makeStdenvCross defaultStdenv crossSystem (binutilsCross crossSystem)
       (gccCrossStageFinal crossSystem);
   
  -  stdenv = 
  +  stdenv =
       if bootStdenv != null then bootStdenv else
         let changer = getConfig ["replaceStdenv"] null;
         in if changer != null then
  
positive.code:   python = if getConfig ["python" "full"] false then pythonFull else pythonBase;
    python25 = if getConfig ["python" "full"] false then python25Full else python25Base;
    python26 = if getConfig ["python" "full"] false then python26Full else python26Base;
    pythonBase = python25Base;
    pythonFull = python25Full;
  
    python24 = import ../development/interpreters/python/2.4 {
      inherit fetchurl stdenv zlib bzip2;
  
negative.code: 
    ncbiCTools = builderDefsPackage ../development/libraries/ncbi {
      inherit tcsh mesa lesstif;
      inherit (xlibs) libX11 libXaw xproto libXt libSM libICE
        libXmu libXext;
    };
  
  