diff --git a/overlay.nix b/overlay.nix
index b8314405e0a498a3c4fb1d67296b4c1db017bb26..e24abad44d8cf3e82b18896d56f385ea4d7a6777 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -6,6 +6,8 @@ final: prev: with pkgs.haskell.lib;
 
   PyF = prev.callHackage "PyF" "0.11.0.0" { };
 
+  Unique = dontCheck (doJailbreak (prev.callHackage "Unique" "0.4.7.9" {}));
+
   algebraic-graphs = prev.callHackage "algebraic-graphs" "0.7" {};
 
   bin = doJailbreak prev.bin;