Clean Architecture Patterns

Build maintainable, testable backends with SOLID principles and hexagonal architecture.

SOLID Principles (2026 Python)

S - Single Responsibility

# BAD: One class doing everything
class UserManager:
    def create_user(self, data): ...
    def send_welcome_email(self, user): ...
    def generate_report(self, users): ...

# GOOD: Separate responsibilities
class UserService:
    def create_user(self, data: UserCreate) -> User: ...