Hi, one of the authors here. We realized that for many CRUD web apps, a library that lets you synchronize "diffsets" (lists of changes the client makes to JavaScript objects) can replace server-side controllers and views, so you don't end up doing MVC on both the server and client.
We reduced web apps to a set of authorization rules and models. You can interact with document-style objects on the client, but keep the power of relational datastores on the server.
It's a relational Firebase for CRUD apps, if you will.
Would love to get some feedback. Thanks!