JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://dl.dropbox.com/u/1015920/Ext/Ext.ux.ajax.SimXhr.js"></script>
<script src="http://dl.dropbox.com/u/1015920/Ext/Ext.ux.ajax.Simlet.js"></script>
<script src="http://dl.dropbox.com/u/1015920/Ext/Ext.ux.ajax.JsonSimlet.js"></script>
<script src="http://dl.dropbox.com/u/1015920/Ext/Ext.ux.ajax.SimManager.js"></script>

JavaScript

/*
http://docs.sencha.com/ext-js/4-0/#!/api/Ext.ux.ajax.SimManager
*/

Ext.define('My.model.Contact', {
    extend:'Ext.data.Model',
    fields:[
        'name',
        'phone'
    ],
    proxy:{
        type:'ajax',
        url:'/contacts',
        reader:{
            type:'json',
            root:'contacts'
        }
    }
});

Ext.application({
    launch:function(){
        
        var sim = Ext.ux.ajax.SimManager.init();
                
        sim.register({
            '/contacts':{
                responseText:'{success:true, contacts:[{"name":"frank", "phone":"6045551212"}]}'
            }
        });        
        
        My.model.Contact.load(1, {
            success:function(){
                console.log(arguments);
            }
        });
    }
});