I forgot to mention the killer feature, which is why we use Styx, apart from our great love for Nix: The ability to easily include content from remote sources.

As Styx uses Nix for getting its inputs, it's just as easy to build a page off a file in your local repository as getting a file from a remote repository, http URL, a whole bunch of files, or anything you can compute or get from a network, really.

In fact, even the default templates in Styx are fetched this way: If you never use them, they never touch your computer, but if you include the standard templates in your site definition, Styx knows to go out and fetch them and put them in the right places.

We use this to get documentation and changelog from our code repository into our web site.