This guy built Redux (which I see as a descendant of re-frame) using Horizon.js (which I see the backend that front-end people can use to make apps) for React apps, and it strikes me as relevant to the discussion about re-frame abstracting backends more and more?: https://medium.com/@roman01la/introducing-react-horizon-4c26f9ef628c#.xynzf6dbn

world as described in https://github.com/Day8/re-frame/wiki/Effectful-Event-Handlers might (for some apps) just live on a remote Horizon db.

Cool!