Senior Next.js / React Frontend Developer to Harden an Internal Dashboard App for Production

# Overview We're a healthcare analytics company with an internal web portal (built in **Next.js 16 / React 19 / TypeScript / Tailwind CSS v4**) that embeds Power BI reports for our partners. The app works, but it was built quickly and needs to be brought up to a **production-quality standard**. It's a small, focused codebase (~2,400 lines), so this is a high-impact, well-scoped engagement — not a sprawling legacy rescue. We're looking for a senior frontend engineer to either **refactor the existingcode or rebuild it from a clean foundation** (your call — we want your recommendation), and to leave us with a maintainable, tested, polished application. # What you'll be working on A single Next.js App Router application that: - Renders a landing/navigation experience and a set of dashboard pages. - Embeds Power BI reports via `powerbi-client-react` ("App Owns Data"). - Reads a small amount of data from Postgres for user settings. **Authentication is fully handled upstream (SSO) and is OUT OF SCOPE.** You will never need credentials, secrets, or access to our production environment. (See "How we work" below.) # Scope of work 1. **Code quality & structure** — Establish a clean, consistent architecture: sensible component structure, strict TypeScript, and tooling (ESLint + Prettier). The repo currently has no linting or formatting setup. 2. **Testing & CI** — Add a testing setup (unit + a few integration/e2e tests for critical paths) and GitHub Actions CI gates (lint, typecheck, test on PR). There are currently **no tests** — establishing this foundation is a core deliverable. 3. **UI / UX polish** — Implement to our provided design direction: responsive layout, proper loading/error/empty states, and a polished feel around the (heavy) Power BI embeds. **We will provide the design/branding** — you implement it well, you don't need to invent the visual identity. 4. **Recommendation up front** — In an early milestone, give us a short written assessment: refactor vs. rebuild, and your proposed approach. **Out of scope:** authentication/SSO, SEO (the app is private and login-gated), backend/Power BI infrastructure, and anything touching production data. # Required skills - Deep, demonstrable experience with **Next.js (App Router)**, **React 19**, and **TypeScript** (strict mode). - **Tailwind CSS** proficiency and a strong eye for implementing designs faithfully. - Experience setting up **testing (e.g. Vitest/Jest + Playwright)** and **CI pipelines (GitHub Actions)** for frontend apps. - A track record of taking quick-build apps to **maintainable, production-grade** quality. ### Nice to have - Prior **Power BI embedding** experience (`powerbi-client-react`, "App Owns Data") - Accessibility (WCAG AA) and frontend performance optimization experience. # How we work (please read) - We operate in a regulated healthcare environment. You will work against a **sanitized copy of the repository** — no real report IDs, secrets, customer data, or production access. All data is mock/synthetic. - **Hourly engagement** via Upwork's tracker, with a cap. We estimate **~40–100 hours**; we'll set a weekly cap and review progress in milestones. - We value clear communication, small reviewable PRs, and your honest technical judgment over just "doing what's asked."