diff --git a/app/index.html b/app/index.html
index 82d70f3..2e0c142 100644
--- a/app/index.html
+++ b/app/index.html
@@ -7,6 +7,7 @@
     </title>
     <!-- Load and bootstrap LIPS. -->
     <script src="https://cdn.jsdelivr.net/npm/lips@beta/dist/lips.min.js" bootstrap></script>
+    <!-- Load Nitinol libraries. -->
     <script type="text/x-scheme">(load "/lib/nitinol/nitinol.scm")</script>
   </head>
   <body>
