anchor.diff: -{ lib, stdenv, fetchurl, callPackage, ncurses, gettext, pkg-config
  +{ lib, stdenv, fetchurl, callPackage, ncurses, bash, gawk, gettext, pkg-config
   # default vimrc
   , vimrc ? fetchurl {
       name = "default-vimrc";
  
positive.code:     "vim_cv_memmove_handles_overlap=yes"
    ];
  
    postInstall = ''
      ln -s $out/bin/vim $out/bin/vi
      mkdir -p $out/share/vim
  
negative.code:   inherit (common) version src postPatch hardeningDisable enableParallelBuilding meta;
  
    nativeBuildInputs = [ gettext pkg-config ];
    buildInputs = [ ncurses bash gawk ]
      ++ lib.optionals stdenv.hostPlatform.isDarwin [ Carbon Cocoa ];
  
    strictDeps = true;
  
    configureFlags = [
      "--enable-multibyte"
  