itsual Anti-Corruption Layer
Overview
An Anti-Corruption Layer (ACL) isolates your model from external models so that external changes or poor designs do not infect your core domain.
When to Use
- Integrating with legacy or poorly modeled external systems
- Consuming third-party APIs whose structure you do not want to adopt
- Mapping between two bounded contexts with different languages
Practices
- Translate external concepts into your own ubiquitous language as early as possible
- Keep the translation logic in a dedicated layer/module
- Avoid leaking external IDs, enums, or structures deep into your domain
- Write tests around the translation boundary
Principles
- Your core domain should speak your language, not the external system’s
- The ACL is a deliberate seam that makes future replacement easier
Verification
- External model changes are mostly absorbed by the ACL
- Core domain code has minimal knowledge of external structures