Stat is a static site generator and an example of how the Longform Markup Language can be used. The setup is very primitive at the moment. To get a feel for what a codebase made using Stat looks like have a look through Stat's repo, especially the _src directory.
Stat will eventually have nicer mechanisms for getting started. For now you want to clone this repo and remove all files specific to https://stat.occultist.dev.