diff --git a/tests/mocha/index.html b/tests/mocha/index.html
index 71b7de6b4..1fa12eb4c 100644
--- a/tests/mocha/index.html
+++ b/tests/mocha/index.html
@@ -4,7 +4,7 @@
     <meta charset="utf-8">
     <title>Mocha Tests for Blockly</title>
 
-    <link href="https://unpkg.com/mocha@5.2.0/mocha.css" rel="stylesheet" />
+    <link href="../../node_modules/mocha/mocha.css" rel="stylesheet" />
     <script src="../../blockly_uncompressed.js"></script>
     <script src="../../generators/dart.js"></script>
     <script src="../../generators/javascript.js"></script>
@@ -38,10 +38,10 @@
 
     <div id="mocha"></div>
     <div id="failureCount" style="display:none" tests_failed="unset"></div>
-    <script src="https://unpkg.com/chai/chai.js"></script>
-    <script src="https://unpkg.com/mocha@5.2.0/mocha.js"></script>
-    <script src="https://unpkg.com/sinon/pkg/sinon.js"></script>
-    <script src="https://unpkg.com/@blockly/dev-tools/dist/index.js"></script>
+    <script src="../../node_modules/chai/chai.js"></script>
+    <script src="../../node_modules/mocha/mocha.js"></script>
+    <script src="../../node_modules/sinon/pkg/sinon.js"></script>
+    <script src="../../node_modules/@blockly/dev-tools/dist/index.js"></script>
     <script>
       mocha.setup({
         ui: 'tdd'