scoped self-import

default.nix

let
  roundTwo = builtins.hasAttr "inScope" builtins;
  pinnedPath = builtins.fetchTarball {
    url = "https://github.com/NixOS/nixpkgs/archive/2b973d233906fb0483263bca71bb789cad61513e.tar.gz";
    sha256 = "11h21zsas7xgdax6xs2lh3mz8spvdk8i63czysr4p69yir1h1cd7";
  };
in
  if roundTwo
    then throw "yep - ${<nixpkgs>}"
    else
      let
        overrides = {
          inScope = true;
          __nixPath = [
            { prefix = "nixpkgs"; path = pinnedPath; }
          ] ++ builtins.nixPath;
          import = fn: scopedImport overrides fn;
          scopedImport = attrs: fn: scopedImport (overrides // attrs) fn;
          builtins = builtins // overrides;
        };
      in
        builtins.scopedImport
          overrides
          ./.