This talk is to give a short overview of the mongrel2 project and share the experience gained while adding the IPv6 support. Mongrel2 is an application, language, and network architecture agnostic web server that focuses on web applications using modern browser technologies. * Language Agnostic with a simple backend protocol supporting Ruby, Ruby through Rack, Python, C++, PHP, Haskell, Common Lisp, Perl, .NET, Clojure, and Lua all written by Mongrel2 fans. * Modern Browser Friendly designed to handle HTTP, Flash XMLSockets, or WebSockets, Long Polling on the same socket transparently. * ZeroMQ Enabled as well as HTTP proxy support so it works with what you have already while giving you new super powers. * Network Architecture Agnostic so you can carve your operations up anyway that reduces costs. * N:M Messaging Patterns means you can have any N handlers answer to any M browsers arbitrarily, but still easy to do plain request/response. * Automation Loving Configs that are easily accessible via any programming language with an Model-View-Controller design. * Modern Internal Design using the Mongrel 1 HTTP parser powering many big companies with a proven security track record, event based I/O, fast coroutines to handle that I/O, and smart reasonable defaults with zero configuration needed usually. * Documented, Documented, Documented We document everything in a well written manual that shows you how to use every feature.