Weighing roughly 45KB, rupy is probably the smallest Java NIO HTTP server in the world.
Rupy is inherently non-blocking asynchronous, which makes it the ideal candidate for high concurrency real-time applications serving dynamic data.
Tested with acme, rupy performs on average ~1500 requests per second (RPS). To put that figure in perspective; acme doesn't use keep-alive, so that means 1500 unique TCP connections serving dynamic content per second! Thanks to NIO and an event queue to avoid selector trashing, this figure degrades gracefully under high concurrency.