anchor.diff:  { stdenv, lib, runCommand, patchelf, makeWrapper, pkg-config, curl
  +, fetchpatch
   , openssl, gmp, zlib, fetchFromGitHub, rustPlatform, libiconv }:
   
   let
  
positive.code:        --subst-var dynamicLinker \
         --subst-var libPath
      '')
    ];
  
    postInstall = ''
      pushd $out/bin
      mv elan-init elan
      for link in lean leanpkg leanchecker leanc leanmake; do
        ln -s elan $link
      done
      popd
  
negative.code: 
  rustPlatform.buildRustPackage rec {
    pname = "elan";
    version = "1.1.0";
  
    src = fetchFromGitHub {
      owner = "leanprover";
      repo = "elan";
      rev = "v${version}";
      sha256 = "0xmml81krr0i18b14dymfdq43szpzws7qj8k404qab51lkqxyxsb";
    };
  
    cargoSha256 = "sha256-xjJ39hoSDn0VUH0YcL+mQBXbzFcIvZ38dPjBxV/yVNc=";
  
    nativeBuildInputs = [ pkg-config makeWrapper ];
  
  