Dependency Contracts

Dependency contracts check that a source layer does not reference forbidden layers.

Groups:

• strict
• audit

Example

contracts:
  strict:
    - id: application-not-infrastructure
      name: application-must-not-depend-on-infrastructure
      source: application
      forbidden: [infrastructure]
      reason: Application code must depend on abstractions, not concrete infrastructure.

Direct and transitive depth

By default, dependency contracts check direct type references.

Use dependency_depth: transitive when indirect paths should also fail:

contracts:
  strict:
    - id: application-not-transitively-infrastructure
      name: application-must-not-transitively-depend-on-infrastructure
      source: application
      forbidden: [infrastructure]
      dependency_depth: transitive
      reason: Application must not have any dependency path into Infrastructure.

Transitive checks are more expensive and should be used when the dependency path matters architecturally.

Ignored violations

Use ignored_violations only for narrow frozen debt:

ignored_violations:
  - source_type: MyApp.Application.Legacy.LegacyUseCase
    forbidden_reference: MyApp.Infrastructure.LegacyGateway
    reason: Existing debt tracked in #123.

For larger adoption work, prefer a generated migration baseline.