Just click the link above, the entire site is Fossils interface.
I believe the site itself is running an instance of Fossil?
That's correct. Fossil is just a single binary and all the 'artifacts' in the repo are stored in a single sqlite file. The built-in server works really well or it can also be used with CGI.
And SCGI as well.
Yep. Cloning it is also a great way to poke around and get a better sense of its functionality.