Backbone is definitely stable and solid, and there's a bunch of good addons in the ecosystem that build on it (particularly Marionette for lifecycle handling an

Backbone is definitely stable and solid, and there's a bunch of good addons in the ecosystem that build on it (particularly Marionette for lifecycle handling and more advanced views, Ampersand for a better Model/State class, and Epoxy for data binding). That said, having built a Backbone app, and then gotten into React+Redux, I'm all in on React and Redux as a better way to build apps. It's a much more consistent mental model, and makes tracing data flow much easier.