solid-principles-ai-kit

To refactor a god class in C# using SOLID principles, you split its multiple responsibilities into cohesive services and collaborators based on the Single Responsibility Principle, then inject those dependencies through interfaces to reduce coupling and improve testability.

The best way to extend C# behavior without modifying existing code is applying the Open/Closed Principle, which replaces fragile if/else patterns with abstractions like strategies and polymorphism to add features safely without breaking existing logic.

Fix .NET inheritance misuse and fat interfaces by applying LSP and ISP SOLID principles, ensuring derived classes properly substitute base classes and splitting bloated interfaces so clients only depend on the specific methods they actually use.

Yes, you can use .NET dependency injection to make brittle C# unit tests easier to mock by applying the Dependency Inversion Principle, injecting dependencies through interfaces rather than concrete implementations to isolate system behavior during testing.

Yes, this SOLID refactoring approach works for setting up .NET dependency injection correctly by mapping design symptoms to SOLID principles and offering actionable C# DI patterns that stabilize unit tests and reduce system brittleness.

You should avoid using the Open/Closed Principle for C# refactoring when simpler direct modifications suffice without introducing premature abstraction complexity, as applying strategies and polymorphism unnecessarily can overcomplicate straightforward feature growth.