Simon Willison’s Weblog

Microsoft’s XUL

24th October 2003

According to this Microsoft blogger the reason IE development has seemed quiet of late is that they’ve been working hard on XAML, an XML Application Markup Language which is a way to create applications in the browser (or out for that matter) [...] It is basically an XML structure with CSS and JavaScript. The CSS defines the appearance and the JavaScript dictates behavior.

Sound familiar? It should do—that’s exactly what XUL does. On the plus side, this completely validates the grossly under-appreciated importance of Mozilla’s biggest secret. On the negative side, this looks set to represent the ultimate browser lock-in—in a few years time when IE 7 comes as standard on new PCs I wouldn’t be surprised to see the corporate software development world moving almost exclusively to this technology—after all, it’s going to be extremely easy both to develop and to distribute and it will have all of the benefits of a web application without the downside of the restricted GUIs offered by HTML.

Of course, Microsoft might make it an open standard. But then I might win the lottery next week.

I wonder if it will be possible to transform XAML in to XUL using XSLT?

Update: It has been pointed out that the author of the above blog entry is not a Microsoft employee.