diff --git a/src/objstore.cc b/src/objstore.cc
index 7ef5d72..434e079 100644
--- a/src/objstore.cc
+++ b/src/objstore.cc
@@ -120,6 +120,8 @@ Value PyObjectWrap::NewCallable(Napi::Env env, PyStrongRef &&py) {
     VERBOSE_PYOBJ(CALL, *py, "Funcstore retrieve");
     assert(!it->second->Value().IsEmpty());
     js = it->second->Value();
+    // The caller expects this to be destroyed
+    py = nullptr;
   }
 
   return js;