The best way to work with vendor prefixes in CSS. Clean and readable CSS3 code. Used by Twitter, WordPress, Bootstrap and CodePen
A must-have plugin. Makes Sidekiq queues smarter by managing them in any way you want (limiting, blocking, pausing, querying)
A Ruby parser implemented from scratch in pure Ruby. Used by various code analysis tools such as Rubocop. More than a million of gem downloads
Build APIs in Rails with integration tests and live web interface
Safe sandboxing compiling template language for Ruby
The number one tool for deploying Ruby on Rails (and not only Rails) projects. We maintain Capistrano 3 and lots of related infrastructure gems.