anchor.diff:  
     nixUnstable = lib.lowPrio (callPackage common rec {
       name = "nix-2.4${suffix}";
  -    suffix = "pre7534_b92f58f6";
  +    suffix = "pre7805_984e5213";
   
       src = fetchFromGitHub {
         owner = "NixOS";
         repo = "nix";
  -      rev = "b92f58f6d9e44f97002d1722bd77bad939824c1c";
  -      sha256 = "1p791961y5v04kpz37g6hm98f1ig7i34inxl9dcj3pbqhf5kicxg";
  -    };
  -
  -    crates = fetchurl {
  -      url = "https://hydra.nixos.org/build/118797694/download/1/nix-vendored-crates-2.4pre7534_b92f58f6.tar.xz";
  -      sha256 = "a4c2612bbd81732bbb899bc0c230e07b16f6b6150ffbb19c4907dedbbc2bf9fc";
  +      rev = "984e521392b3f41f7cdab203e5c00f3e00e27a28";
  +      sha256 = "1dch48018dwzx9cysnfxrdpszav87s0d635zqw810mgmqpm25fw8";
       };
   
       inherit storeDir stateDir confDir boehmgc;
  
positive.code:           brotli boost editline
          ]
          ++ lib.optional (stdenv.isLinux || stdenv.isDarwin) libsodium
          ++ lib.optionals is24 [ libarchive rustc cargo ]
          ++ lib.optional withLibseccomp libseccomp
          ++ lib.optional withAWS
              ((aws-sdk-cpp.override {
  
negative.code: 
    nixFlakes = lib.lowPrio (callPackage common rec {
      name = "nix-2.4${suffix}";
      suffix = "pre20200622_334e26b";
  
      src = fetchFromGitHub {
        owner = "NixOS";
        repo = "nix";
        rev = "334e26bfc2ce82912602e8a0f9f9c7e0fb5c3221";
        sha256 = "14a2yyn1ygymlci6hl5d308fs3p3m0mgcfs5dc8dn0s3lg5qvbmp";
      };
  
      inherit storeDir stateDir confDir boehmgc;
  