📦 Parcel : Blazing fast, zero configuration web application bundler
csscss : csscss will parse any CSS files you give it and let you know which rulesets have duplicated declarations.
YAML Builder : A tool for visual layout development of YAML based CSS layouts
Babel : Babel will turn your ES6+ code into ES5 friendly code, so you can start using it right now without waiting for browser support.
* { CSS:resetr } : To help you find the perfect CSS-reset styles, CSSresetr lets you try all the best CSS Resets on a variety of web pages – even your own.
Compass is an open-source CSS Authoring Framework.