Enforcement

Deterministic extraction requires architectural conventions. Enforcement ensures code follows those conventions.

The Extraction-Enforcement Cycle

Enforcement makes extraction reliable. Extraction validates enforcement is working.

Demo Application

See enforcement in action in the ecommerce demo app:

View ecommerce-demo-app →

The demo shows:

• Decorators marking components
• Extraction config detecting them
• ESLint enforcement ensuring coverage

Why Enforcement Matters

Without enforcement, extraction becomes unreliable:

• False negatives — Components missing conventions won't be detected
• Extraction drift — New code doesn't match config rules
• Silent failures — Missing components go unnoticed until architecture is incomplete

Enforcement prevents this. When all code follows conventions, extraction is reliable and complete.

Enforcement Approaches

Static Analysis (Linters)

Use linters to enforce conventions at write-time.

Advantages:

• Immediate feedback in IDE
• Catches issues before commit
• Low friction for developers

Examples:

• ESLint rules requiring decorators (TypeScript)
• ArchUnit tests for package structure (Java)
• Pylint custom checkers (Python)

TypeScript ESLint Enforcement →

Architecture Tests

Write tests that verify architectural conventions.

Advantages:

• Explicit validation
• Runs in CI
• Customizable rules

Examples:

// Verify all classes in domain/ are decorated
test('all domain classes have component decorators', () => {
  const files = glob.sync('src/domain/**/*.ts')
  const violations = findUndecoratedClasses(files)
  expect(violations).toEqual([])
})

CI Gates

Block merges when extraction fails or components are missing.

Advantages:

• Prevents drift
• Enforces at team level
• Visible in PR checks

Example workflow:

- name: Extract Architecture
  run: riviere extract --config extraction.config.yaml
- name: Validate Component Count
  run: |
    COUNT=$(riviere extract --dry-run | grep 'Total:' | awk '{print $2}')
    if [ $COUNT -lt 50 ]; then
      echo "Expected at least 50 components, found $COUNT"
      exit 1
    fi

Code Review

Include extraction validation in code review checklist.

Advantages:

• Human judgment
• Catches edge cases
• Educational for team

Checklist items:

• New API methods have @APIEndpoint decorator
• Domain logic uses @DomainOp decorator
• Events extend DomainEvent base class

Language-Specific Implementation

Different languages require different enforcement mechanisms:

Language	Static Analysis	Architecture Tests	CI Gates
TypeScript	ESLint	Vitest + ts-morph	✓
Java	ArchUnit	JUnit + ArchUnit	✓
Python	Pylint	pytest + ast	✓
C#	Roslyn Analyzers	xUnit + Roslyn	✓

TypeScript Example

For TypeScript, we provide an ESLint plugin that enforces component decorators.

TypeScript Enforcement Guide →

See Also

• Deterministic Extraction Overview — How deterministic extraction works
• TypeScript Enforcement — ESLint implementation