diff --git a/overlays/30-ghc.nix b/overlays/30-ghc.nix
index 4d76ece2..4536d343 100644
--- a/overlays/30-ghc.nix
+++ b/overlays/30-ghc.nix
@@ -15,6 +15,7 @@ let
         cabal-install dhall taskwarrior pandoc hlint cabal2nix weeder
         reflex-dom password optics shh-extras neuron hspec-discover paths
         hmatrix postgresql-simple snap hedgehog nix-derivation req
+        witch
         ;
     } // makeHaskellScriptPackages p;
 in