diff --git a/src/pyodide.js b/src/pyodide.js
index cdf89175d..37a6e3fdd 100644
--- a/src/pyodide.js
+++ b/src/pyodide.js
@@ -1,3 +1,4 @@
+"use strict";
 /**
  * The main bootstrap script for loading pyodide.
  */