Can DI be used without a DI container?

Short answer: How? Yes, DI can be implemented manually without using a DI container. You simply pass dependencies through constructors or methods: public class OrderService

Example code

{
private readonly IOrderRepository _repo;
public OrderService(IOrderRepository repo)
{
_repo = repo;
}
} // Manual injection var repo = new OrderRepository();
var service = new OrderService(repo); This is suitable for small or simple applications, though not scalable for large apps.

Real-world example (ShopNest)

Patterns in ShopNest should solve a real pain (swappable payments, test seams)—not be added for decoration.

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.