nixos/nix: properly use makeWrapper hook

nix-os/nix.nix

@@ -5,13 +5,14 @@
 }:
 
 let
-  makeWrapper = "${pkgs.makeWrapper}/nix-support/setup-hook";
   # bool -> nixpkgs[]
   wrappedNixExecutables = inEnvironment: assert builtins.isBool inEnvironment; pkgs.symlinkJoin {
     name = "${pkgs.nix.name}-wrap";
     paths = [ pkgs.nix ];
+    nativeBuildInputs = [
+      pkgs.makeWrapper
+    ];
     postBuild = ''
-      . ${makeWrapper}
       wrapProgram $out/bin/nix-build \
         --add-flags "--log-format" \
         --add-flags "bar${lib.optionalString inEnvironment "-with-logs"}"
@@ -24,8 +25,10 @@ let
   wrappedNixosExecutables = pkgs.symlinkJoin {
     name = "${pkgs.nixos-rebuild.name}-wrap";
     paths = [ pkgs.nixos-rebuild ];
+    nativeBuildInputs = [
+      pkgs.makeWrapper
+    ];
     postBuild = ''
-      . ${makeWrapper}
       wrapProgram $out/bin/nixos-rebuild \
         --add-flags "--log-format" \
         --add-flags "bar"