diff --git a/overlay.nix b/overlay.nix
index d42b1b59891489c13c8481df56dc962d6cb4314b..b9cb42dd0655e1a9481d5f3e54fba0838baf1018 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -131,6 +131,8 @@ final: prev: with pkgs.haskell.lib; {
 
   foundation = prev.callHackage "foundation" "0.0.29" { };
 
+  generic-lens-core = prev.callHackage "generic-lens-core" "2.2.1.0" { };
+
   generic-lens-lite = doJailbreak (prev.callHackage "generic-lens-lite" "0.1" { });
 
   generic-optics-lite = doJailbreak (prev.callHackage "generic-optics-lite" "0.1" { });