Grav is a brilliantly thought out flat file CMS. It's a joy to work with and templates are really nice to build with because Twig support is baked in. I just launched http://gravity-training.co.uk for a client built with Grav. The support and community are also top notch. Good luck with Product Hunt today.
(PS. I originally found out about Grav originally here, which reinforces how useful PH is!).
