diff --git a/Gruntfile.js b/Gruntfile.js
index d5c201ad38..fba98aab27 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -80,7 +80,7 @@ module.exports = function(grunt) {
     'populist:test'
   ]);
 
-  grunt.registerTask('test', ['build:test', 'phantom:run']);
+  grunt.registerTask('test', ['build:test', 'build:basic', 'phantom:run']);
   grunt.registerTask('npm:test', ['build', 'npm:pack']);
 
   // Optimized build task that does all of our builds. The subtasks will be run
diff --git a/src/environment/__tests__/ReactWebWorker-test.js b/src/environment/__tests__/ReactWebWorker-test.js
new file mode 100644
index 0000000000..87f093f8c0
--- /dev/null
+++ b/src/environment/__tests__/ReactWebWorker-test.js
@@ -0,0 +1,50 @@
+/**
+ * Copyright 2013 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * @jsx React.DOM
+ * @emails react-core
+ */
+
+/*jslint evil: true */
+
+"use strict";
+
+describe('ReactWebWorker', function() {
+  it('can run React in a web worker', function() {
+    var done = false;
+    var error;
+
+    var worker = new Worker('/worker.js');
+    worker.addEventListener('message', function(e) {
+      var data = JSON.parse(e.data);
+      if (data.type == 'error') {
+        error = data.message + "\n" + data.stack;
+      } else {
+        expect(data.type).toBe('done');
+        done = true;
+      }
+    });
+
+    waitsFor(function() {
+      return done;
+    });
+    runs(function() {
+      if (error) {
+        console.log(error);
+        throw new Error(error);
+      }
+    });
+  });
+});
diff --git a/src/test/all.js b/src/test/all.js
index 75d347b897..3549f081b3 100644
--- a/src/test/all.js
+++ b/src/test/all.js
@@ -2,38 +2,7 @@
 // modules in src/test and to specify an ordering on those modules, since
 // some still have implicit dependencies on others.
 
-var Ap = Array.prototype;
-var slice = Ap.slice;
-var Fp = Function.prototype;
-
-if (!Fp.bind) {
-  // PhantomJS doesn't support Function.prototype.bind natively, so
-  // polyfill it whenever this module is required.
-  Fp.bind = function(context) {
-    var func = this;
-    var args = slice.call(arguments, 1);
-
-    function bound() {
-      var invokedAsConstructor = func.prototype && (this instanceof func);
-      return func.apply(
-        // Ignore the context parameter when invoking the bound function
-        // as a constructor. Note that this includes not only constructor
-        // invocations using the new keyword but also calls to base class
-        // constructors such as BaseClass.call(this, ...) or super(...).
-        !invokedAsConstructor && context || this,
-        args.concat(slice.call(arguments))
-      );
-    }
-
-    // The bound function must share the .prototype of the unbound
-    // function so that any object created by one constructor will count
-    // as an instance of both constructors.
-    bound.prototype = func.prototype;
-
-    return bound;
-  };
-}
-
+require("./phantomjs-shims");
 require("ReactTestUtils");
 require("reactComponentExpect");
 require("mocks");
diff --git a/src/test/phantomjs-shims.js b/src/test/phantomjs-shims.js
new file mode 100644
index 0000000000..12fe3bba9c
--- /dev/null
+++ b/src/test/phantomjs-shims.js
@@ -0,0 +1,35 @@
+(function() {
+
+var Ap = Array.prototype;
+var slice = Ap.slice;
+var Fp = Function.prototype;
+
+if (!Fp.bind) {
+  // PhantomJS doesn't support Function.prototype.bind natively, so
+  // polyfill it whenever this module is required.
+  Fp.bind = function(context) {
+    var func = this;
+    var args = slice.call(arguments, 1);
+
+    function bound() {
+      var invokedAsConstructor = func.prototype && (this instanceof func);
+      return func.apply(
+        // Ignore the context parameter when invoking the bound function
+        // as a constructor. Note that this includes not only constructor
+        // invocations using the new keyword but also calls to base class
+        // constructors such as BaseClass.call(this, ...) or super(...).
+        !invokedAsConstructor && context || this,
+        args.concat(slice.call(arguments))
+      );
+    }
+
+    // The bound function must share the .prototype of the unbound
+    // function so that any object created by one constructor will count
+    // as an instance of both constructors.
+    bound.prototype = func.prototype;
+
+    return bound;
+  };
+}
+
+})();
diff --git a/src/test/worker.js b/src/test/worker.js
new file mode 100644
index 0000000000..2918cb6e4d
--- /dev/null
+++ b/src/test/worker.js
@@ -0,0 +1,20 @@
+/* jshint worker: true */
+"use strict";
+
+// The UMD wrapper tries to store on `global` if `window` isn't available
+var global = {};
+importScripts("phantomjs-shims.js");
+
+try {
+  importScripts("react.js");
+} catch (e) {
+  postMessage(JSON.stringify({
+    type: 'error',
+    message: e.message,
+    stack: e.stack
+  }));
+}
+
+postMessage(JSON.stringify({
+  type: 'done'
+}));
diff --git a/test/phantom-harness.js b/test/phantom-harness.js
index c07142ccad..c89f971a44 100644
--- a/test/phantom-harness.js
+++ b/test/phantom-harness.js
@@ -50,16 +50,19 @@ server.listen(port, function(req, res) {
   var content;
 
   switch (file) {
+  case "jasmine.js":
+  case "react.js":
   case "react-test.js":
     file = "../build/" + file;
     break;
 
-  case "jasmine.css":
-    file = "../vendor/jasmine/" + file;
+  case "phantomjs-shims.js":
+  case "worker.js":
+    file = "../src/test/" + file;
     break;
 
-  case "jasmine.js":
-    file = "../build/" + file;
+  case "jasmine.css":
+    file = "../vendor/jasmine/" + file;
     break;
 
   case "":