LLDbeginner

Repository Pattern

Repository abstracts persistence so domain code does not depend directly on SQL, ORM, or storage-specific details. It is common in clean architecture and domain-driven design.

Reading time

8 min

repositoryclean architecturedddpersistence

Why Repositories Help

Business logic should not care whether data lives in SQL, NoSQL, or memory. Repositories provide a stable contract to retrieve and persist domain entities.

Benefits

  • Easier mocking in tests
  • Cleaner separation of concerns
  • Less storage detail leakage into domain code

Caution

Repositories should stay focused on persistence, not become giant service objects containing business logic.

Interview Tip

Use repository pattern when persistence matters but should stay behind an abstraction.