Single Page App Framework
This is an SPA CMS framework. It is designed to be a customizable framework, having some similar concepts to populare CMSs like WordPress, such as themes.
While the backend is PHP powered, and themes could create the site through PHP, the majority of the framework is devoted to the API and a database interface, not template building - meaning there aren't tools in place to help much with templating in PHP.
For example, the default theme uses React/Redux, so the (default) APIs don't even send HTML content back, but raw JSON objects for React to parse and display.
I'll also note that I've left the build files/scripts in the repo, so that you can make updates/PR's as you see fit.
It is currently under construction, so star/follow for updates.