Rwasa is described as 'rwasa is a full-featured, high performance, scalable web server designed to compete with the likes of nginx. It has been built from the ground-up in x86_64 assembly language' and is an app in the Development category. There are three alternatives to Rwasa for Linux, Mac, Windows and BSD. The best alternative is nginx, which is both free and Open Source. Other great apps like Rwasa are lighttpd (Free, Open Source) and Cherokee (Free, Open Source).
nginx [engine x] is a HTTP and reverse proxy server, as well as a mail proxy server written by Igor Sysoev. It has been running for more than five years on many heavily loaded Russian sites including Rambler (RamblerMedia.com).