Redux is the React framework that other flux frameworks recommend you use. It went 1.0.0 when I started writing this (and is at the time of publishing past 3.0.0!) and it’s still early days as to how to use it.
I just migrated off RequireJS to Webpack, having last week moved from ES5 to ES6. One more migration to go and we’re running a totally 2015 compliant webapp (React+Backbone -> something Flux-ish)!
Have you heard? We aren’t beholden to old versions of Internet Explorer any more! And though we don’t have to expect everyone to have version 72 of your favourite browser yet, we can still program as if they do thanks to the kind folks at Babel.