Beyond SOLID: Embracing CUPID for Modern Software Craftsmanship

For decades, the SOLID principles — Single Responsibility, Open-Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion — have been the undisputed gold standard of object-oriented design. They were forged in an era of monolithic desktop applications and strict C++ or Java hierarchies. However, as our industry has shifted toward microservices, serverless functions, and dynamic languages, many developers find that strictly following SOLID can lead to “over-engineering.