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Testing Tutorial

Ship Confidently — From Unit Tests to AI-Powered QA. Work through 17 free lessons at your own pace — every one with runnable examples you can edit.

Start with Why Testing Matters

Testing Fundamentals

  1. 1Why Testing Matters
  2. 2Types of Tests: Unit, Integration, E2E
  3. 3Writing Your First Tests with Vitest
  4. 4Testing React Components

Test-Driven Development

  1. 5What Is TDD and Why It Works
  2. 6The Red-Green-Refactor Cycle
  3. 7TDD for API Routes and Server Actions
  4. 8TDD with AI: Writing Specs That Generate Tests

Advanced Testing Patterns

  1. 9Mocking, Stubs, and Test Doubles
  2. 10Testing Async Code and API Calls
  3. 11End-to-End Testing with Playwright
  4. 12Testing Database Interactions

AI-Assisted Testing & Tools

  1. 13AI Test Generation: Tools and Techniques
  2. 14Testing AI Features: LLM Outputs and Prompts
  3. 15Code Coverage and Quality Metrics
  4. 16The Testing Toolchain: Choosing the Right Stack
  5. 17Building a Testing Culture