Layer Violation

ID: layer_violation | Severity: High (default)

Layer violation occurs when code in one architectural layer imports code from a layer it shouldn't know about (e.g., Domain layer importing from Infrastructure).

Why this is a smell

• Breaks Abstraction: Internal implementation details leak into high-level business logic.
• Testing Difficulty: Business logic becomes hard to test without mocks for infrastructure (DB, API, etc.).
• Rigidity: Changing a database or external library requires changing the core business logic.

Configuration

You must define your layers in .archlint.yaml:

rules:
  layer_violation:
    layers:
      - name: domain
        path: ['**/domain/**']
        allowed_imports: [] # Domain imports nothing

      - name: application
        path: ['**/application/**']
        allowed_imports: ['domain']

      - name: infrastructure
        path: ['**/infrastructure/**']
        allowed_imports: ['domain', 'application']

ESLint Rule

This detector is available as an ESLint rule for real-time feedback in your editor.

// eslint.config.js
export default [
  {
    rules: {
      '@archlinter/no-layer-violations': 'error',
    },
  },
];

See ESLint Integration for setup instructions.

How to fix

1. Dependency Inversion: Define an interface in the higher layer (Domain) and implement it in the lower layer (Infrastructure).
2. Refactor: Move the misplaced code to the appropriate layer.