Dependency inversion, SOLID principles in ASP.NET Core?

Short answer: Apply Dependency Inversion Principle by coding against abstractions (interfaces), not implementations. Follow SOLID principles: Single Responsibility: Each class has one reason to change. Open/Closed: Classes open for extension, closed for modification. Liskov Substitution: Subtypes can replace base types. Interface Segregation: Use multiple specific interfaces. Dependency Inversion: Depend on abstractions.

Real-world example (ShopNest)

A ShopNest checkout request flows through middleware, hits a minimal API or controller, uses scoped services, and returns ProblemDetails on errors.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.