Testing Strategy

Testing strategy:

Unit tests (70%)

• Test individual functions/components
• Fast, isolated, deterministic
• Mock dependencies
• Example: Jest, Vitest

Integration tests (20%)

• Test component interactions
• Test API endpoints
• Test database queries
• Example: Supertest, Testing Library

E2E tests (10%)

• Test user workflows
• Test real browser behavior
• Slow, flaky, expensive
• Example: Playwright, Cypress, Nightwatch

The test pyramid:

    /\     E2E (few)
   /  \
  /    \   Integration (some)
 /______\
         Unit (many)

Rule of thumb: If you can test it at unit level, don't test it at E2E level.