diff --git a/overlay.nix b/overlay.nix
index 6d2af14b..e889d0e7 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -1,12 +1,18 @@
 final: /* Future last stage */
 prev:  /* Previous stage */
 
-with final.lib;
-
 let
+
+  inherit (prev) lib;
+  inherit (lib) collect filterAttrs isDerivation mapAttrs;
+
   callPackage = final.callPackage;
 
-  bscPkgs = {
+  mkStrict = drv: if (isDerivation drv && drv ? overrideAttrs && !(drv ? strictDeps))
+    then drv.overrideAttrs { strictDeps = true; }
+    else drv;
+
+  bscPkgs = mapAttrs (_: mkStrict) {
     amd-uprof = prev.callPackage ./pkgs/amd-uprof/default.nix { };
     bench6 = callPackage ./pkgs/bench6/default.nix { };
     bigotes = callPackage ./pkgs/bigotes/default.nix { };