Using IConfiguration to read settings?

Short answer: Inject IConfiguration anywhere: public class MyService {

Example code

private readonly string _apiKey;
public MyService(IConfiguration config) {
_apiKey = config["MySettings:ApiKey"];
}
} You can also access nested settings via config.GetSection("MySettings").

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.