diff --git a/pkgs/havm/default.nix b/pkgs/havm/default.nix
index d8856a5..2e15de7 100644
--- a/pkgs/havm/default.nix
+++ b/pkgs/havm/default.nix
@@ -10,7 +10,10 @@ stdenv.mkDerivation rec {
 
   buildInputs = [
     ghc
-    which # Used by tests
+  ];
+
+  checkInputs = [
+    which
   ];
 
   doCheck = true;