If you’re a web designer or developer, you’re well acquainted with prototyping. From raw wireframing to creating interfaces in Photoshop, designers map out how sites will work before they create them. Over the past few years, the protoyping process has changed significantly. With browser makers generally agreeing on web standards and the rise of tools such as Firebug and WebKit’s web inspector, we can sometimes skip Photoshop and go straight to the browser. Plus, JavaScript frameworks like jQuery let us play with browser events with only a few lines of code. But what if we need to do even more? As websites increasingly become web apps, we now need to prototype backend functionality, too. Learn how Sinatra, a so-called “micro” web framework, helps you create real (albeit simple) web apps extremely fast, letting you prototype flows and behavior you may want to integrate into a final product.