anchor.diff:  { stdenv, lib, fetchFromGitHub, emscripten }:
   
  -let version = "0.8.7"; in
  +let version = "0.8.9"; in
   
   stdenv.mkDerivation {
     name = "jsonnet-${version}";
  
positive.code:     rev = "v${version}";
      owner = "google";
      repo = "jsonnet";
      sha256 = "0adg7ijz10mc4xs5lfrby5g9sx96icf6cg39hvkh4wqjl85c6i9g";
    };
  
    buildInputs = [ emscripten ];
  
negative.code: 
    meta = {
      description = "Purely-functional configuration language that helps you define JSON data";
      maintainers = with lib.maintainers; [ benley copumpkin ];
      license = lib.licenses.asl20;
      homepage = https://github.com/google/jsonnet;
      platforms = lib.platforms.unix;
  