diff --git a/upng.js b/upng.js
index 339e821ea5acdd0869f0915d72828a62f1520a83..15c1a3d3da2d99aece0807a5375971fe45829d4e 100644
--- a/upng.js
+++ b/upng.js
@@ -4,7 +4,7 @@
  * commit cb463cb7b857fc1fbd47bb8628c536e02aaa24ce
  * license: MIT License, Copyright (c) 2017 Photopea
  */
-module.exports = UPNG = {};
+var UPNG = {}; module.exports = UPNG;