diff --git a/moo/kernel/Moo.moo b/moo/kernel/Moo.moo
index e208969..60bd6f3 100644
--- a/moo/kernel/Moo.moo
+++ b/moo/kernel/Moo.moo
@@ -11,6 +11,6 @@
 #include 'Stream.moo'.
 
 /* -------------------------------------------------------------------------- */
-//#include 'FFI.moo'.
+#include 'FFI.moo'.
 #include 'Stdio.moo'.
 #include 'Console.moo'.