I need a clean, well-structured test suite that lifts my React codebase to at least 90 % line coverage, as reported by Jest. The stack is React 18 with functional components and hooks, so I expect tests to exercise logic, UI behaviour, and data flow in realistic scenarios. The work breaks down into three layers that all have to be in place: • Unit tests – isolate individual components and utilities. • Integration tests – stitch key pieces together to validate context, reducers, and side-effects. • End-to-end tests – drive the app through the browser to mirror real user journeys. Focus points are user authentication (sign-in, sign-out, protected routes), dynamic form handling (validation, conditional fields, error states), and API interactions (mocked fetch/axios calls, optimistic UI, error retries). Deliverables • All test files organised next to the source or in a dedicated __tests__ folder. • Updated Jest config and any required setup (React Testing Library, mock servers, coverage thresholds). • A final coverage report showing ≥ 90 % lines. • A concise README describing how to run the suite locally and in CI. Acceptance criteria Tests run with a single command, pass consistently, and no existing functionality is broken. The pull request must include the coverage badge or screenshot proving the 90 % goal. I review merge requests promptly and give fast feedback so we can land this quickly. Looking forward to your expertise in squeezing every meaningful line of coverage out of the app without over-mocking or duplicating effort.