diff --git a/default.nix b/default.nix
index 15cb165..841f76d 100644
--- a/default.nix
+++ b/default.nix
@@ -9,6 +9,6 @@ let
     want = filterAttrs (name: type:
         type == "directory" && (substring 0 1 name) != "."
     ) (readDir here);
-in mapAttrs (name: type:
-    callPackage (import (here + "/" + name))
-) want
+in (mapAttrs (name: type:
+    callPackage (import ((toString here) + "/" + (toString name)))
+) want)