Back in 2006 I was really embracing emerging AJAX frameworks like Prototype, YUI, and jQuery. One night while on a YUI forum, I stumbled across a guy who posted a really cool grid component based on YUI. His name was Jack Slocum. I started using his component immediately. His component quickly grew in popularity, and he started creating other components. Soon ExtJS 1.0 was born. I begin implementing it on commercial projects immediately. I have continued to use ExtJS on all web GUI projects, having completed a recent customer portal for WalMart with ExtJS 5.1. I have written several custom ExtJS components along the way. I'm an active ExtJS community member. I have lots of ExtJS experience on numerous commercial projects that have been running in production for up to 5 years. I've upgraded ExtJS 2.x to ExtJS 3.x, and recently from ExtJS 3.x to ExtJS 5.x. I can provide screen shots of ExtJS GUIs I have developed upon request.