diff --git a/Integrations/FileStorage.js b/Integrations/FileStorage.js
index 8b9182850..04d55c12a 100644
--- a/Integrations/FileStorage.js
+++ b/Integrations/FileStorage.js
@@ -180,7 +180,7 @@ exports.newFileStorage = function newFileStorage() {
   }
 
   function mkDirByPathSync(targetDir, { isRelativeToScript = false } = {}) {
-    const sep = path.sep;
+    const sep = '/';
     const initDir = path.isAbsolute(targetDir) ? sep : '';
     const baseDir = isRelativeToScript ? __dirname : '.';