diff --git a/wh-engine/serialization.lisp b/wh-engine/serialization.lisp
index 0e52b19..63d59e3 100644
--- a/wh-engine/serialization.lisp
+++ b/wh-engine/serialization.lisp
@@ -100,14 +100,14 @@
   (declare (ignore environment))
   (values
    ;; cons form
-   `(sb-kernel::new-instance ,(class-name (class-of obj)))
+   `(allocate-instance (find-class ',(class-name (class-of obj))))
    ;; init form
    (loop for slot in (sb-mop:class-slots (class-of obj))
          for slot-name = (sb-mop:slot-definition-name slot)
-         collect slot-name into slots
-         collect (make-value-init-form (slot-value obj slot-name))
-           into values
-         finally (return `(sb-pcl::set-slots ,obj ,slots ,@values)))
+         nconc `((slot-value ,obj ',slot-name)
+                 ,(make-value-init-form (slot-value obj slot-name)))
+           into setfs
+         finally (return `(setf ,@setfs)))
    ))
 
 (defun make-value-init-form (x)