Use the prop-types npm module (React.PropTypes is being deprecated)

lib/shuffle.js

@@ -14,6 +14,10 @@ var _reactDom = require('react-dom');
 
 var _reactDom2 = _interopRequireDefault(_reactDom);
 
+var _propTypes = require('prop-types');
+
+var _propTypes2 = _interopRequireDefault(_propTypes);
+
 var _objectAssign = require('object-assign');
 
 var _objectAssign2 = _interopRequireDefault(_objectAssign);
@@ -146,10 +150,10 @@ var Shuffle = _react2.default.createClass({
   displayName: 'Shuffle',
 
   propTypes: {
-    duration: _react2.default.PropTypes.number,
-    scale: _react2.default.PropTypes.bool,
-    fade: _react2.default.PropTypes.bool,
-    initial: _react2.default.PropTypes.bool
+    duration: _propTypes2.default.number,
+    scale: _propTypes2.default.bool,
+    fade: _propTypes2.default.bool,
+    initial: _propTypes2.default.bool
   },
 
   getDefaultProps: function getDefaultProps() {

package.json

@@ -6,6 +6,7 @@
   "dependencies": {
     "babel-plugin-transform-object-rest-spread": "^6.16.0",
     "object-assign": "^4.0.1",
+    "prop-types": "^15.6.1",
     "react-addons-transition-group": "^15.0.0 || ^0.14.0",
     "react-tween-state": "^0.1.5"
   },

src/shuffle.js

@@ -3,6 +3,7 @@
 
 import React from 'react';
 import ReactDom from 'react-dom';
+import PropTypes from 'prop-types';
 import assign from 'object-assign';
 import tweenState from 'react-tween-state';
 import ReactTransitionGroup from 'react-addons-transition-group';
@@ -121,10 +122,10 @@ const Shuffle = React.createClass({
   displayName: 'Shuffle',
 
   propTypes: {
-    duration: React.PropTypes.number,
-    scale: React.PropTypes.bool,
-    fade: React.PropTypes.bool,
-    initial: React.PropTypes.bool
+    duration: PropTypes.number,
+    scale: PropTypes.bool,
+    fade: PropTypes.bool,
+    initial: PropTypes.bool
   },
 
   getDefaultProps() {