anchor.diff:      wrapProgram "$out/bin/cargo" \
         --suffix PATH : "${rustc}/bin" \
         --set CARGO_HTTP_CAINFO "${cacert}/etc/ssl/certs/ca-bundle.crt" \
  -      --set SSL_CERT_FILE "${cacert}/etc/ssl/certs/ca-bundle.crt" \
  -      ${stdenv.lib.optionalString stdenv.isDarwin ''--suffix DYLD_LIBRARY_PATH : "${rustc}/lib"''}
  +      --set SSL_CERT_FILE "${cacert}/etc/ssl/certs/ca-bundle.crt"
     '';
   
     checkPhase = ''
  
positive.code: 
    nativeBuildInputs = [ pkgconfig ];
    buildInputs = [ file curl python openssl cmake zlib makeWrapper libgit2 ]
      # FIXME: Use impure version of CoreFoundation because of missing symbols.
      # CFURLSetResourcePropertyForKey is defined in the headers but there's no
      # corresponding implementation in the sources from opensource.apple.com.
      ++ stdenv.lib.optionals stdenv.isDarwin [ darwin.apple_sdk.frameworks.CoreFoundation libiconv ];
  
    LIBGIT2_SYS_USE_PKG_CONFIG=1;
  
    postInstall = ''
      # NOTE: We override the `http.cainfo` option usually specified in
  
negative.code: { stdenv, fetchFromGitHub, file, curl, pkgconfig, python, openssl, cmake, zlib
  , makeWrapper, libiconv, cacert, rustPlatform, rustc, libgit2, darwin
  , version, srcSha, cargoSha256
  , patches ? [] }:
  
  let
    inherit (darwin.apple_sdk.frameworks) CoreFoundation;
  in
  
  rustPlatform.buildRustPackage rec {
    name = "cargo-${version}";
  