juniorClean Architecture
What are Use Cases (Interactors)?
Updated Apr 28, 2026
Short answer
Use Cases orchestrate the flow of data to and from entities, implementing application-specific business rules.
Deep explanation
Use Cases contain the 'how-to' of the application. While Entities represent general business rules, Use Cases describe specific tasks like 'Create an Account' or 'Transfer Funds'. They direct the entities to use their critical business rules to achieve the goals of the use case.
Real-world example
A 'Checkout' use case that coordinates the shopping cart entity and the payment gateway adapter.
Common mistakes
- Putting heavy logic in the Controller instead of the Use Case.
Follow-up questions
- Can a Use Case depend on a specific database?