anchor.diff:    });
   
     nixUnstable = lib.lowPrio (callPackage common rec {
  -    name = "nix-2.4${suffix}";
  +    pname = "nix";
  +    version = "2.4${suffix}";
       suffix = "pre20210326_dd77f71";
   
       src = fetchFromGitHub {
  
positive.code:   , withLibseccomp ? lib.any (lib.meta.platformMatch stdenv.hostPlatform) libseccomp.meta.platforms, libseccomp
    , withAWS ? !enableStatic && (stdenv.isLinux || stdenv.isDarwin), aws-sdk-cpp
    , enableStatic ? stdenv.hostPlatform.isStatic
    , name, suffix ? "", src
    , patches ? [ ]
    }:
    let
       sh = busybox-sandbox-shell;
       nix = stdenv.mkDerivation rec {
        inherit name src patches;
        version = lib.getVersion name;
  
        is24 = lib.versionAtLeast version "2.4pre";
  
  
negative.code:   nix = nixStable;
  
    nixStable = callPackage common (rec {
      pname = "nix";
      version = "2.3.10";
      src = fetchurl {
        url = "https://nixos.org/releases/nix/${pname}-${version}/${pname}-${version}.tar.xz";
        sha256 = "a8a85e55de43d017abbf13036edfb58674ca136691582f17080c1cd12787b7ab";
      };
  
  