Context A critical checkout flow has no automated tests. Regressions are only discovered in production, causing revenue loss. The Problem The engineering team lacks an automated testing strategy covering user-visible behavior across the full checkout journey. Constraints Write Playwright tests covering: product selection, cart update, form validation, and successful order submission. Mock API responses for deterministic test runs. Assert on accessible roles and text content rather than CSS selectors. Expected Deliverable A Playwright test suite covering the full React checkout flow, using API mocking, role-based selectors, and assertions on visible UI state.