diff --git a/conf/karma.conf.js b/conf/karma.conf.js
index 1d7f7fa..9ba1a10 100644
--- a/conf/karma.conf.js
+++ b/conf/karma.conf.js
@@ -13,6 +13,7 @@ module.exports = function(karma) {
       'ShadowDOM/node_modules/chai/chai.js',
       'ShadowDOM/shadowdom.js',
       'ShadowDOM/test/test.main.js',
+      {pattern: 'ShadowDOM/build.json', included: false},
       {pattern: 'ShadowDOM/src/**/*.js', included: false},
       {pattern: 'ShadowDOM/test/**/*.js', included: false},
       {pattern: 'ShadowDOM/test/**/*.html', included: false},
diff --git a/test/js/build-json.js b/test/js/build-json.js
index 83806ba..7632085 100644
--- a/test/js/build-json.js
+++ b/test/js/build-json.js
@@ -12,18 +12,20 @@ suite('build.json', function() {
 
   test('Ensure lists match', function(done) {
     var xhrJson = new XMLHttpRequest;
-    xhrJson.open('GET', '../build.json');
+    // karma serves the test runner at /context.html, need to adjust xhr request url to match
+    var requestBase = window.__karma__ ? '/base/ShadowDOM/' : '../';
+    xhrJson.open('GET', requestBase + 'build.json');
     xhrJson.onload = function() {
       var buildJson = JSON.parse(xhrJson.responseText);
 
       var xhrJs = new XMLHttpRequest;
-      xhrJs.open('GET', '../shadowdom.js');
+      xhrJs.open('GET', requestBase + 'shadowdom.js');
       xhrJs.onload = function() {
         var sources = [];
 
         document.write = function(s) {
           var path =
-              s.slice('<script src="../'.length, - '"><\/script>'.length);
+              s.slice(('<script src="' + requestBase).length, - '"><\/script>'.length);
           sources.push(path);
         };