clean-architecture

To decouple business logic from infrastructure, apply the Clean Architecture pattern to strictly enforce the Dependency Rule, ensuring source code dependencies point exclusively inward toward higher-level policies and remain independent of external details.

Evaluating system boundaries and SOLID principle adherence involves running an architectural diagnostic that scores component cohesion and dependency management based on seven Quick Diagnostic rows defined in the skill documentation.

Structure a new microservice for long-term maintainability by defining clear module boundaries and enforcing the Dependency Inversion principle, which separates core business rules from infrastructure to create clean, testable units.

Tightly coupled code makes systems fragile because business logic becomes inextricably linked to frameworks, databases, and UI, meaning any external change risks breaking core rules and significantly increases modification costs.

Yes, you can use this approach on an existing web application by analyzing the current project architecture to identify where business rules violate the Dependency Rule, then refactoring to decouple core logic from specific frameworks.

You should avoid Clean Architecture when the system is too small to justify the overhead of strict module boundary definition and dependency inversion, as enforcing the Dependency Rule on trivial logic adds unnecessary complexity.