Ember.js

 Ember.js  (sometimes called just Ember ) is a JavaScript framework that uses MVC (model view controller) in the browser (using Mustache as its templating language).

Not a good fit

 * https://twitter.com/manton2/status/827575815663665154 "Taking a fresh look at this codebase. I had mixed feelings removing Ember.js, but now that I’ve started it’s the right call. Not a good fit"