Progressive enhancement

Progressive enhancement is a feature that is very important for a lot of people. Knowing about this, Metal.js is prepared to deal with content that already comes rendered from the server. Since metal components use incremental dom by default, rendering on an element with existing content will reuse it instead of repainting everything.

It's important to note that building components with soy also helps with progressive enhancement in another way: by providing a faithful template that can be run by the server without having to duplicate the rendering code or run JavaScript at all.