PHP: https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-2-coding-style-guide.md Ruby: https://github.com/thoughtbot/guides/tree/master/style#ruby Rails https://github.com/bbatsov/rails-style-guide Javascript: https://github.com/airbnb/javascript HTML & CSS: http://mdo.github.io/code-guide/