So what is a data-driven framework? It means, I can create a simple MVC controller, with a model, pass it to a view and it renders on the client-side. Yes, as a Single Page Application. YetaWF uses the "Module" concept. It's an extra level, which makes it all possible. For example, on this page you're currently reading, there are quite a few modules used. The menu on top of the page is a module. The Login button in the upper right corner of the page is a module. The comments section below, yes, another module. If you scroll all the way down, you'll see a "Scroll-to-top" arrow in the bottom right corner of the page. Another module.
If you click on a link, let's say one of the main menu entries, like "Home", only the modules on the new page are actually replaced, not the entire page. This means about 2 MB of code is not downloaded, or executed, because it's already loaded. jQuery is already present, Kendo UI, is already present (and many more). The menu was already loaded. So was the Scroll-to-top module. That is the true advantage of client-site Single Page Applications.
In other words, with YetaWF, you can basically develop a "plain-old" MVC application, using modules, but still with just models, controllers and views, and magically, you have a Single Page Application.
Is YetaWF as fast and as efficient as a true client-side framework? Maybe, maybe not, definitely close. But the effort to get to a YetaWF SPA is a fraction of rewriting everything. Even if you're starting from scratch, using the YetaWF approach lets you leverage server-side programming (server-side developers) to get a SPA.
Server-side Single Page Application. Really? But yes, it's real.