diff --git a/packages/daemon/src/web-page.js b/packages/daemon/src/web-page.js
index da6209f9e9..abb358cc90 100644
--- a/packages/daemon/src/web-page.js
+++ b/packages/daemon/src/web-page.js
@@ -65,6 +65,8 @@ const hardenedEndowments = harden({
   TextEncoder,
   TextDecoder,
   URL,
+  // This one is important for exo to work.
+  Promise,
 });
 
 const globalProps = collectPropsAndBind(window);
@@ -74,8 +76,8 @@ delete globalProps.NaN;
 delete globalProps.Infinity;
 
 const endowments = Object.freeze({
-  ...hardenedEndowments,
   ...globalProps,
+  ...hardenedEndowments,
   process: {
     env: {},
   },