>>5
Really nginx does a lot of the job, it serves html pages directly without asking Scheme for instance. A lot of the routing too. That's how things get reasonably optimized.
I did a lot of research for a fast Scheme web server, Guile was the fastest by far but still a bit behind what could be done.
Chez Scheme is disappointing there. There's a nice chinese project with bindings for libuv but it's awfully unstable: https://github.com/guenchi/Igropyr