My thoughts exactly! Apart from embedded systems (or using it as embedded in an application, e.g. to provide an application's help system via an internal web browser) I'd find it weird to build websites in C. I'm looking for something along these lines for embedded systems, but GLib & external webserver disqualify balde. Still looks like a nice, clean project, though I was disappointed to find out I can't try it out :)
C may have some shortcomings, particulary policing memory vioations, but can be very lightweight and very fast.
Remember, Linux and Apache/NGINX are in C . Implementing the site specifics in C isn't that much of a stretch.
The extra speed could even make your site that much more useable.