John Crepezzi is a Software Engineer at Jane Street. He possess expertise in ruby, ruby on rails, javascript, php, java and 32 more skills. He is proficient in Italian. Colleagues describe him as "John Crepezzi is a genius who builds amazing software, is incredibly productive, and never sleeps. He is a 10x developer who will do what's required and discover many related things that no one else ever thought of but are incredibly valuable. He will certainly be a billionaire someday and I will happily drive his "other other Benz" as a chauffer or do whatever he needs." and "John is a _monster_. I don't know how he managed to release an open source library almost every single week and have the time to work on almost every feature that Patch launched, but he did it. Besides being absolutely prolific (just check out his Github profile: https://github.com/seejohnrun) John is also just a fantastically awesome guy to have around! He truly loves writing code and delivering features that users love, and his passion is infectious."