mixins

Ruby modules enable code sharing across classes without inheritance. I use include for instance methods, extend for class methods. prepend inserts module before class in method lookup. Concerns organize shared behavior—validations, scopes, association

Mixins let me compose view behavior without duplication. LoginRequiredMixin is essential for protecting views. I create custom mixins like UserOwnershipMixin to encapsulate common patterns. Mixin order matters due to Python's MRO—I put Django's mixins