Most software developers tend to write code where objects are given too many responsibilities. Code with bloated objects is more difficult to test, to understand and to maintain in the long run. To keep the code small and focused, different strategies can be used to extract behavior. A new gem, “casting”, claims to bring the benefits of both mix-ins and delegation, but without their drawbacks. Read more: https://discuss.gemnasium.com/t/casting-adding-behavior-to-objects-without-using-extend/34