diff --git a/pkgs/top-level/default.nix b/pkgs/top-level/default.nix
index 12329d0af82f..421e0299e2d8 100644
--- a/pkgs/top-level/default.nix
+++ b/pkgs/top-level/default.nix
@@ -79,17 +79,16 @@ let
   inherit (lib) throwIfNot;
 
   checked =
-    throwIfNot (lib.isList overlays) "The overlays argument to nixpkgs must be a list." lib.foldr
-      (x: throwIfNot (lib.isFunction x) "All overlays passed to nixpkgs must be functions.")
-      (r: r)
-      overlays
-      throwIfNot
-      (lib.isList crossOverlays)
-      "The crossOverlays argument to nixpkgs must be a list."
-      lib.foldr
-      (x: throwIfNot (lib.isFunction x) "All crossOverlays passed to nixpkgs must be functions.")
-      (r: r)
-      crossOverlays;
+    (throwIfNot (lib.isList overlays) "The overlays argument to nixpkgs must be a list.")
+      (lib.foldr (
+        x: throwIfNot (lib.isFunction x) "All overlays passed to nixpkgs must be functions."
+      ) lib.id overlays)
+      (throwIfNot (lib.isList crossOverlays) "The crossOverlays argument to nixpkgs must be a list.")
+      (
+        lib.foldr (
+          x: throwIfNot (lib.isFunction x) "All crossOverlays passed to nixpkgs must be functions."
+        ) lib.id crossOverlays
+      );
 
   localSystem = lib.systems.elaborate args.localSystem;