An architectural doctrine for NestJS projects: a breakdown of typical codebase degradation scenarios and the structural constraints that keep them from emerging as the feature set grows. This article is a breakdown of how a typical NestJS backend degrades as the feature set grows, and how the ideas of Clean Architecture make it possible to avoid that. I'll walk through the full cycle: show on a "before and after" example how the feature-based structure that today is pushed as the standard loses control with scale; dissect the typical degradation scenarios; estimate in money and engineer-hours what they cost the business; explain why this kind of codebase forces teams to break monoliths into microservices long before it's justified. After that, I'll propose an approach designed against degradation — and back it with a formal mathematical argument. By the end of the article, you'll have both the reasoning and the tools to apply this approach to your own systems.…