Monkey patching is extremely useful in Ruby but it has to be done with great care. Not having monkey patching available in an OO codebase comes with a lot of he

Monkey patching is extremely useful in Ruby but it has to be done with great care. Not having monkey patching available in an OO codebase comes with a lot of headaches. Small example: You're using a 3rd party library that happens to include layers of object inheritance. You notice a piece of functionality a couple of layers up that you need access to or actually requires correction, but wasn't exposed in a way that you can fix it. With monkey patching, you can add a couple of lines of code in your code base that corrects the library without any changes elsewhere. Then you add a test to monitor it to see if something ever changes. Without monkey patching, you have to fork the entire 3rd party library, make the change, use your fork on your project, keep it up to date and hope the library owner eventually accepts your PR. OR use the code as is and rebuild the inheritance tree in your own code base everywhere it's impacted. It's indispensable when this scenario comes up.