diff --git a/test.lisp b/test.lisp
index f362c4d..8cfe478 100644
--- a/test.lisp
+++ b/test.lisp
@@ -1,7 +1,10 @@
 ;; Common Lisp
 
-(defun gcd (a b)
-    (if (> b 0) (gcd b (mod a b)) a)
+(require '#:package-locks)
+(ext:without-package-locks
+    (defun gcd (a b)
+        (if (> b 0) (gcd b (mod a b)) a)
+    )
 )
 
 (princ "test")