How would you answer an interview scenario involving Dependency Inversion Principle?

For an interview scenario involving Dependency Inversion Principle, I would first clarify the business goal, scale, constraints, and the failure or quality attribute the interviewer wants to explore. DIP says high-level policy should depend on abstractions rather than concrete low-level implementation details. In this scenario, a billing service directly creates a Stripe client. Explain how DIP would change the dependency structure. For production, place abstractions near the policy that owns the need and inject infrastructure implementations at composition boundaries. I would then explain the main alternatives and tradeoffs, identify likely failure modes, and describe how I would validate the solution through testing, observability, security controls, and recovery or rollback planning.