diff --git a/src/lisp/test-args.lisp b/src/lisp/test-args.lisp
new file mode 100644
index 0000000..14364a8
--- /dev/null
+++ b/src/lisp/test-args.lisp
@@ -0,0 +1,7 @@
+(defun with-optional (required (optional 3))
+  (+ required optional))
+
+(defun main ()
+  (when t
+    (print (with-optional 2))
+    (print (with-optional 2 4))))