solution-testing

Use the Page Object Model so each page encapsulates its selectors and actions, and keep raw locators out of test files. Prefer getByRole and getByLabel locators, and wait on observable state like toBeVisible instead of fixed timeouts.

Follow the honeycomb model: many unit tests, more integration tests, and few targeted E2E tests. Reserve E2E tests for critical journeys like login, checkout, and core workflows, and cover edge cases at lower levels.

Common causes are hardcoded waitForTimeout calls, shared test data across parallel runs, order-dependent tests, and network variability. Replace sleeps with state assertions, generate unique test data per run, and increase CI timeouts in config.

Use BDD when product owners, QA, and developers need shared readable test documentation for complex business rules. Skip it for small teams where tickets already capture intent, since step definition overhead outweighs the benefit.

Include only checks where failure means the system is unusable: health endpoint returning 200, home page loading, and a successful login. Run it automatically after every deployment and roll back immediately if it fails.

Quarantine it with test.fixme and link a tracking issue instead of deleting it, which preserves coverage history and intent. Fix and re-enable it within the same sprint to avoid eroding trust in the suite.