anchor.diff:        ln -s rustup $link
       done
       popd
  +
  +    wrapProgram $out/bin/rustup --prefix "LD_LIBRARY_PATH" : "${libPath}"
   
       # tries to create .rustup
       export HOME=$(mktemp -d)
  
positive.code:   cargoBuildFlags = [ "--features no-self-update" ];
  
    patches = lib.optionals stdenv.isLinux [
      (let
        libPath = lib.makeLibraryPath [
          zlib # libz.so.1
        ];
      in
        (runCommand "0001-dynamically-patchelf-binaries.patch" { CC=stdenv.cc; patchelf = patchelf; libPath = "$ORIGIN/../lib:${libPath}"; } ''
         export dynamicLinker=$(cat $CC/nix-support/dynamic-linker)
         substitute ${./0001-dynamically-patchelf-binaries.patch} $out \
           --subst-var patchelf \
           --subst-var dynamicLinker \
           --subst-var libPath
      '')
      )
    ];
  
    doCheck = !stdenv.isAarch64 && !stdenv.isDarwin;
  
negative.code: 
    cargoSha256 = "0ghjrx7y25s6rjp06h0iyv4195x7daj57bqza01i1j4hm5nkhqhi";
  
    nativeBuildInputs = [ makeWrapper pkgconfig ];
  
    buildInputs = [
      curl zlib
  