They've blogged about their enhancements here: http://www.rubyraptor.org/how-we-made-raptor-up-to-4x-faster-than-unicorn-and-up-to-2x-faster-than-puma-torquebox

They've blogged about their enhancements here: http://www.rubyraptor.org/how-we-made-raptor-up-to-4x-faster-than-unicorn-and-up-to-2x-faster-than-puma-torquebox/ http://www.rubyraptor.org/how-we-made-raptor-up-to-4x-faster... and Part II: http://www.rubyraptor.org/pointer-tagging-linked-string-hash-tables-turbocaching-and-other-raptor-optimizations/ http://www.rubyraptor.org/pointer-tagging-linked-string-hash...