anchor.diff:            lib.optionals stdenv.isLinux [
               "--with-boost=${boost}/lib"
               "--with-sandbox-shell=${sh}/bin/busybox"
  +          ]
  +          ++ lib.optionals (stdenv.isLinux && !(isStatic && stdenv.system == "aarch64-linux")) [
               "LDFLAGS=-fuse-ld=gold"
             ];
   
  
positive.code:       devShells = forAllSystems (system:
          forAllStdenvs (stdenv:
            with nixpkgsFor.${system};
            with commonDeps pkgs;
            nixpkgsFor.${system}.${stdenv}.mkDerivation {
              name = "nix";
  
  
negative.code:         # we want most of the time and for backwards compatibility
          forAllSystems (system: stdenvsPackages.${system} // stdenvsPackages.${system}.stdenvPackages);
  
        commonDeps = { pkgs, isStatic ? false }: with pkgs; rec {
          # Use "busybox-sandbox-shell" if present,
          # if not (legacy) fallback and hope it's sufficient.
          sh = pkgs.busybox-sandbox-shell or (busybox.override {
  