As a language, Ruby plays fast and loose with the type system. Developers rely on duck typing to check that the things they want to do with an object are permissible. Whilst this freedom makes writing code frictionless and often a whole lot of fun, it doesn't always scale up well to writing larger systems. I can't promise that strong duck typing - adding automated checking to inter-object interfaces - will make writing complex systems easy but it will help you think about how to structure code in new ways and bring some of the lessons learned from other languages to the Ruby community.