Every new web app at PayPal starts with TypeScript
&gt;&gt; What took took me so long?<p>It took a while for all of Microsoft&#x27;s marketing to kick in and for the mindless hypewagon to reach full speed.<p>I have decades of experience with Typed ECMAScript (first with ActionScript 3 from 2006 and then TypeScript). It&#x27;s not worth it. Productivity will drop enormously and bug density will not change at all.