LowType introduces the concept of "type expressions" in method arguments. When an argument's default value resolves to a type instead of a value then it's treated as a type expression. Now you can have types in Ruby in the simplest syntax possible

Raindeer is an event-driven framework using the dynamic features and latest async improvements in Ruby + some weird ideas, to build a new breed of web application. Each Raindeer component can be used individually in your existing application, or all together as a cohesive framework. Deer to be different.

Raindown is a templating layer for static site generation and an annotation framework for Markdown files.