anchor.diff:  
     stage4 = with stage3; stageFun 4 stage3 {
       shell = "${pkgs.bash}/bin/bash";
  -    extraInitialPath = [ pkgs.bash ];
  +    extraBuildInputs = with pkgs; [ xz darwin.CF libcxx pkgs.bash ];
       extraPreHook = ''
         export PATH_LOCALE=${pkgs.darwin.locale}/share/locale
       '';
  
positive.code:   stageFun = step: last: {shell             ? "${bootstrapTools}/bin/sh",
                            overrides         ? (pkgs: {}),
                            extraPreHook      ? "",
                            extraBuildInputs  ? with last.pkgs; [ xz darwin.CF libcxx ],
                            extraInitialPath  ? [],
                            allowedRequisites ? null}:
      let
        thisStdenv = import ../generic {
  
negative.code:     # enables patchShebangs above. Unfortunately, patchShebangs ignores our $SHELL setting
      # and instead goes by $PATH, which happens to contain bootstrapTools. So it goes and
      # patches our shebangs back to point at bootstrapTools. This makes sure bash comes first.
      extraBuildInputs = with pkgs; [ xz darwin.CF libcxx pkgs.bash ];
  
      extraPreHook = ''
        export PATH=${pkgs.bash}/bin:$PATH
        export PATH_LOCALE=${pkgs.darwin.locale}/share/locale
      '';
  
  