Automattic, the creator of WordPress, has been keeping something big under wraps. But as of today we know what’s going on: WordPress.com has been completely stripped down and rebuilt in JavaScript and API calls – and now it’s all open-source. There’s also an official Mac desktop app, with Windows and Linux counterparts coming soon.

The admin design has been simplified to feel more modern and further accommodate everyone using the CMS. In a blog post written by WordPress creator Matt Mullenweg, he says that the overhaul happened because the interface was being held back by “backward compatibility and working without JavaScript.” At that point, it was decided that a step-by-step approach wouldn’t give the results he wanted and Calypso (the re-launch codename) was born. Now, after “more than 20 months of work” it’s here.

WordPress.com is already a giant – it’s used by up to 25 percent of the Web – but that isn’t enough by itself. As companies mature they can lose steam and falter, and Mullenweg hopes that Calypso is a big step in the other direction. “One of the hardest things to do in technology is disrupt yourself,” Mullenweg says. Let’s see if WordPress.com can do it.