diff --git a/basis/alien/destructors/destructors.factor b/basis/alien/destructors/destructors.factor
index 8b3be72cea..fdc752e78c 100644
--- a/basis/alien/destructors/destructors.factor
+++ b/basis/alien/destructors/destructors.factor
@@ -3,6 +3,8 @@
 USING: functors destructors accessors kernel parser words ;
 IN: alien.destructors
 
+SLOT: alien
+
 FUNCTOR: define-destructor ( F -- )
 
 F-destructor DEFINES ${F}-destructor