Unextendable originated from the thought of being able to implement the "State pattern":http://tobyho.com/Design_Patterns_Revisited%3A_State within object instances using modules. In other words: I wanted object instances to behave dependent on their state using modules. I really want to use modules because they are commonly used to define a set of methods which you can extend within an object instance. Unfortunately, you cannot just unexclude a module. So after searching the web for solutions, I came across Mixology, evil-ruby and StatePattern. But they slightly did not fit the picture. So after doing some research, I came up with Unextendable.