Dependency Inversion is the practice of programming to an interface rather than a concrete implementation . In a standard approach, your business logic depends directly on specific tools or SDKs, making the code rigid and difficult to test. With Dependency Inversion, you define a "contract" (an interface) that describes what a service should do, and your application only interacts with that contract.

More in Github .

In this example, we will walk through a common real-world scenario: Analytics . You’ll see how to decouple your Flutter app from specific vendors like Firebase or Facebook, allowing you to swap services, run mock versions in tests, or use a simple console logger during development—all without changing a single line of your feature logic.

The Problem

Rigid Coupling: Your code is smeared with third-party SDKs.…