anchor.diff:  
   with stdenv.lib;
   
  -let version = "4.1.18"; in
  -
  -stdenv.mkDerivation {
  +let
  +  version = "4.1.18";
  +  forEachModule = action: ''
  +    for makefile in $sourcedir/out/linux.*/release/bin/src/*/Makefile \
  +                    $sourcedir/out/linux.*/release/bin/additions/src/*/Makefile
  +    do
  +      mod="$(dirname "$makefile")"
  +      export INSTALL_MOD_PATH="$out"
  +      export INSTALL_MOD_DIR=misc
  +      make -C "$MODULES_BUILD_DIR" "M=$mod" DEPMOD=/do_not_use_depmod ${action}
  +    done
  +  '';
  +in stdenv.mkDerivation {
     name = "virtualbox-${version}-${kernel.version}";
   
     NIX_CFLAGS_COMPILE="-I${kernel}/lib/modules/${kernel.modDirVersion}/build/include/generated";
  
positive.code:   '';
  
    configurePhase = ''
      ./configure --with-qt4-dir=${qt4} \
        ${optionalString (!javaBindings) "--disable-java"} \
        ${optionalString (!pythonBindings) "--disable-python"} \
  
negative.code:   buildPhase = ''
      source env.sh
      kmk
      ${forEachModule "modules"}
    '';
  
    installPhase = ''
  