anchor.diff:    buildPhase = ''
       source env.sh
       kmk
  +    ${forEachModule "modules"}
     '';
   
     installPhase = ''
  
positive.code: 
  with stdenv.lib;
  
  let version = "4.1.18"; in
  
  stdenv.mkDerivation {
    name = "virtualbox-${version}-${kernel.version}";
  
    NIX_CFLAGS_COMPILE="-I${kernel}/lib/modules/${kernel.modDirVersion}/build/include/generated";
  
negative.code:     cp -av * $libexec
  
      # Install kernel modules
      ${forEachModule "modules_install"}
  
      # Create wrapper script
      mkdir -p $out/bin
  