diff --git a/default.nix b/default.nix
index a6b9510ccf0ce3194a086c9e17325be4be9a7210..0cc22a9dac12e9673382451a50e084631b8fd16e 100644
--- a/default.nix
+++ b/default.nix
@@ -20,7 +20,7 @@ let
     # the haskell.nix functionality itself as an overlay.
     (haskellNix.nixpkgsArgs // {
       overlays = haskellNix.nixpkgsArgs.overlays ++ [
-        (import ./oldnix/overlays.nix)
+        (import ./oldnix/overlay.nix)
       ];
     });
 in pkgs.haskell-nix.project {