diff --git a/src/context.c b/src/context.c
index 13618d2..fab0752 100644
--- a/src/context.c
+++ b/src/context.c
@@ -459,6 +459,13 @@ gc_traverse_call_stack_entry(struct call_stack_entry cse, gc_visitor visitor, vo
 
         visit_nullable_scope(cse.func.scope, visitor, opaque);
         visit_nullable_scope(cse.func.closure_scope, visitor, opaque);
+
+        if (cse.func.matcher != NULL) {
+            visitor(
+                opaque,
+                GC_OBJECT_FROM(cse.func.matcher, GC_TYPE_MATCHER)
+            );
+        }
         break;
     case CSE_CFUNCTION:
         visitor(