If you build Web sites, you probably use Javascript libraries. If so, you are probably grateful to the nameless heroes who make these libraries not suck.

One common problem these brave soldiers of the Web have to face is encapsulation. You know, one of them turtles on which the Object-Oriented Programming foundation sits, upon which stands most of the modern software engineering. How do you create that boundary between the code that you wrote and the code that will consume it?

With the exception of SVG (more on that later), today’s Web platform offers only one built-in mechanism to isolate one chunk of code from another — and it ain’t pretty. Yup, I am talking about iframes. For most encapsulation needs, frames are too heavy and restrictive.