anchor.diff:      license = [ licenses.asl20 licenses.mit ];
       maintainers = [ maintainers.havvy ];
       platforms = platforms.all;
  -
  -    # Because CoreServices needs to be updated,
  -    # but Apple won't release the source.
  -    broken = stdenv.isDarwin;
     };
   }
  
positive.code: { stdenv, fetchFromGitHub, rustPlatform, CoreServices }:
  
  rustPlatform.buildRustPackage rec {
    name = "mdbook-${version}";
  
negative.code: 
    cargoSha256 = "0kcc0b2644qbalz7dnqwxsjdmw1h57k0rjrvwqh8apj2sgl64gyv";
  
    buildInputs = stdenv.lib.optionals stdenv.isDarwin [
      CoreServices
      # This is needed to avoid an undefined symbol error for "_CFURLResourceIsReachable"
      darwin.cf-private
    ];
  
    meta = with stdenv.lib; {
      description = "Create books from MarkDown";
  