Adding Tests to Your Bolt.new Project

Most Bolt.new projects ship with zero tests. This means every change is a gamble — you might fix one thing and break three others without knowing until a user reports it. Tests are automated checks that verify your app works correctly. They run in seconds and catch bugs before your users do.

Bolt generates no tests. Set up the testing framework that matches your stack — Vitest for Vite apps, Jest or Vitest for Next.js. Add Playwright for E2E tests. You may need to refactor some code to make it testable (extracting logic from UI components)

Start with the most critical user paths — can a user sign up, use the core feature, and complete the main workflow? Write integration tests for any API endpoints. Test form validation and error states. If there's payment processing, test the complete checkout flow

Unit tests check individual functions in isolation — does this function calculate the right total? Integration tests check that multiple pieces work together — does submitting this form save to the database? End-to-end (E2E) tests simulate a real user — can someone sign up, log in, and complete a purchase? Start with E2E tests for your most critical flows, then add integration tests for your API endpoints.

Set up your tests to run automatically on every code push using GitHub Actions or a similar CI service. This way, you'll know immediately if a change breaks something. A basic CI pipeline runs your tests, checks for TypeScript errors, and builds the project. If any step fails, the push is flagged before it reaches production.