Ask HN: Best tiny JavaScript framework?

I'm deciding on a Javascript framework to use in building a real time chat application with a tiny footprint. I can't use React, Angular, Ember, or Vue because they are too large. I would build the app in vanilla Javascript, but I fear that it will become more and more difficult to maintain and I will end up reimplementing many already solved problems. Some of the frameworks that I've seen that are small, fast, and well-liked are Preact, Inferno, Mithril, and Ractive. Does anyone have any experience with these, or even better, thoughts on a comparison between them?