diff --git a/lib/login.js b/lib/login.js
index 9ddd9a0..6489408 100644
--- a/lib/login.js
+++ b/lib/login.js
@@ -84,6 +84,6 @@ export default async function () {
     existing = await fs.readFile(file, 'utf8');
     existing = JSON.parse(existing);
   } catch (err) {}
-  const config = Object.extend({}, existing, loginData);
+  const config = Object.assign({}, existing, loginData);
   return fs.writeFile(file, JSON.stringify(config));
 }