A very simple and lightweight JavaScript tweening engine.

var target = {value: 0.0};
Tween.to(target, 1.0, {value: 1.0})
// optional delay
.wait(0.5)
// optional easing function
.ease(Tween.Quint.inOut)
// attach lifecycle callbacks
.start(function(){
console.log('started');
})
.step(function(tween){
console.log('step', tween.progress);
})
.done(function(){
console.log('done');
})