diff --git a/js/Permutation.ts b/js/Permutation.ts
index a5aa971..2a421ef 100644
--- a/js/Permutation.ts
+++ b/js/Permutation.ts
@@ -7,7 +7,6 @@
  */
 
 import dot from './dot.js';
-import './Utils.js';
 import Utils from './Utils.js';
 
 class Permutation {
diff --git a/js/Utils.js b/js/Utils.js
index 3d7dd28..34f700b 100644
--- a/js/Utils.js
+++ b/js/Utils.js
@@ -8,6 +8,7 @@
 
 import dot from './dot.js';
 import Vector2 from './Vector2.js';
+import Vector3 from './Vector3.js';
 
 // constants
 const EPSILON = Number.MIN_VALUE;
@@ -304,7 +305,7 @@ const Utils = {
     epsilon = epsilon === undefined ? 1e-5 : epsilon;
 
     // center is the origin for now, but leaving in computations so that we can change that in the future. optimize away if needed
-    const center = new dot.Vector3( 0, 0, 0 );
+    const center = new Vector3( 0, 0, 0 );
 
     const rayDir = ray.direction;
     const pos = ray.position;
diff --git a/js/UtilsTests.js b/js/UtilsTests.js
index f4da38f..60cd48c 100644
--- a/js/UtilsTests.js
+++ b/js/UtilsTests.js
@@ -80,11 +80,11 @@ QUnit.test( 'lineLineIntersection', assert => {
 QUnit.test( 'lineSegmentIntersection', assert => {
   const h = Utils.lineSegmentIntersection;
 
-  const p1 = dot.Vector2.ZERO;
-  const p2 = new dot.Vector2( 1, 1 );
-  const p3 = new dot.Vector2( -10, 8 );
-  const p4 = new dot.Vector2( -3, -3 );
-  const p5 = new dot.Vector2( 8, -10 );
+  const p1 = Vector2.ZERO;
+  const p2 = new Vector2( 1, 1 );
+  const p3 = new Vector2( -10, 8 );
+  const p4 = new Vector2( -3, -3 );
+  const p5 = new Vector2( 8, -10 );
 
   const f = ( p1, p2, p3, p4 ) => h( p1.x, p1.y, p2.x, p2.y, p3.x, p3.y, p4.x, p4.y );
 
diff --git a/tests/playground.html b/tests/playground.html
index c300aac..557b7f2 100644
--- a/tests/playground.html
+++ b/tests/playground.html
@@ -23,10 +23,12 @@
   window.assertions.enableAssert();
   window.assertions.enableAssertSlow();
 
-  import dot from '../js/main.js';
-  import phetCore from '../../phet-core/js/main.js';
+  import phetCore from '../../chipper/dist/js/phet-core/js/main.js';
+  import axon from '../../chipper/dist/js/axon/js/main.js';
+  import dot from '../../chipper/dist/js/dot/js/main.js';
 
   window.dot = dot;
+  window.axon = axon;
   window.phetCore = phetCore;
 
   console.log( 'loaded' );