anchor.diff: -{ system ? builtins.currentSystem }:
  -
  -with import ../../.. { inherit system; };
  -
  -rec {
  +{ pkgspath ? ../../.., test-pkgspath ? pkgspath }:
  +
  +with import pkgspath { system = builtins.currentSystem; };
  +
  +let
  +  llvmPackages = llvmPackages_38;
  +in rec {
     coreutils_ = coreutils.override (args: {
       # We want coreutils without ACL support.
       aclSupport = false;
  
positive.code: 
    # The ultimate test: bootstrap a whole stdenv from the tools specified above and get a package set out of it
    test-pkgs = let
      stdenv = import ./. { inherit system bootstrapFiles; };
    in import ../../.. {
      inherit system;
      bootStdenv = stdenv.stdenvDarwin;
    };
  
negative.code: 
        cp -rL ${llvmPackages.clang-unwrapped}/lib/clang $out/lib
  
        cp -d ${llvmPackages.libcxx}/lib/libc++*.dylib $out/lib
        cp -d ${llvmPackages.libcxxabi}/lib/libc++abi*.dylib $out/lib
  
        mkdir $out/include
        cp -rd ${llvmPackages.libcxx}/include/c++     $out/include
  
        cp -d ${icu.out}/lib/libicu*.dylib $out/lib
        cp -d ${zlib.out}/lib/libz.*       $out/lib
  