anchor.diff:  
   let
     neovimLuaEnv = lua.withPackages(ps:
  -    (with ps; [ mpack lpeg luabitop ]
  +    (with ps; [ lpeg luabitop mpack ]
       ++ optionals doCheck [
           nvim-client luv coxpcall busted luafilesystem penlight inspect
         ]
  
positive.code:     enableParallelBuilding = true;
  
      buildInputs = [
        libtermkey
        libuv
        msgpack
        ncurses
        libvterm-neovim
        unibilium
        gperf
        neovimLuaEnv
      ] ++ optional withJemalloc jemalloc
        ++ optional stdenv.isDarwin libiconv
        ++ optionals doCheck [ glibcLocales procps ]
  
negative.code:     disallowedReferences = [ stdenv.cc ];
  
      cmakeFlags = [
        "-DGPERF_PRG=${gperf}/bin/gperf"
        "-DLUA_PRG=${neovimLuaEnv.interpreter}"
      ]
      ++ optional doCheck "-DBUSTED_PRG=${neovimLuaEnv}/bin/busted"
      ++ optional (!lua.pkgs.isLuaJIT) "-DPREFER_LUA=ON"
  