Senior Full Stack Engineer, Unified Experience

About Us Fanatics is building a leading global digital sports platform. We ignite the passions of global sports fans and maximize the presence and reach for our hundreds of sports partners globally by offering products and services across Fanatics Commerce, Fanatics Collectibles, and Fanatics Betting & Gaming, allowing sports fans to Buy, Collect, and Bet. Through the Fanatics platform, sports fans can buy licensed fan gear, jerseys, lifestyle and streetwear products, headwear, and hardgoods; collect physical and digital trading cards, sports memorabilia, and other digital assets; and bet as the company builds its Sportsbook and iGaming platform. Fanatics has an established database of over 100 million global sports fans; a global partner network with approximately 900 sports properties, including major national and international professional sports leagues, players associations, teams, colleges, college conferences and retail partners, 2,500 athletes and celebrities, and 200 exclusive athletes; and over 2,000 retail locations, including its Lids retail stores. Our more than 22,000 employees are committed to relentlessly enhancing the fan experience and delighting sports fans globally.  About the Role Support Fanatics Collect’s Unified Experience initiative, building seamless collector journeys across Fanatics Live, Marketplace, Instant Rips, Collections, Topps, and future experiences. Today a collector can win a card in a live show, rip a pack, buy on the marketplace, and store it all in a vault, but those moments still feel like separate products. Your job is to make them feel like one. That means building the shared surfaces, APIs, and front-end systems that connect experiences built independently, without slowing any of them down. This is a hands-on senior role with a  frontend-leaning  center of gravity. You’ll own meaningful slices of the unified experience end to end (UI through API contract), primarily in TypeScript, React, and Next.js on Vercel, with  GraphQL as the owned front-to-back contract . You’ll partner with a Staff Backend Engineer, mobile engineers, product, and design. Why Join Us Fanatics Collect is growing fast, and the unification work is the highest-leverage engineering investment we have: every new app, drop, and live format gets easier once the shared foundation exists. You’ll work across mobile, web, and internal tools, with real autonomy and a short path from idea to production. Your teammates are passionate about the space and most of them are collectors themselves. Product Context and Scale Our surfaces reach millions of collectors across iOS, Android, and web, with live, high-traffic moments (breaks, drops, auctions closing) that make performance, accessibility, internationalization, and reliability non-negotiable. You’ll work across multiple existing products with real users and real data, so migration, backward compatibility, and careful rollout are part of the craft. First 90 Days Ship a meaningful, user-facing piece of the unified experience end to end. Build a working map of how Live, Marketplace, Instant Rips, Collections, and Topps fit together today: data models, identity, entitlements, and the seams between them. Establish working relationships with the backend, mobile, product, and design partners you’ll depend on. Identify one piece of duplicated or divergent logic across surfaces and make the case for consolidating it. Responsibilities Design, build, and maintain fullstack features with a frontend lean: TypeScript, React, Next.js, and Vercel, plus backend work in Python/FastAPI (or equivalent) when the feature needs it. Own GraphQL (and related API) contracts for what you ship: schema collaboration, generated types, validation, and compatibility. Treat contract drift as a bug. Build scalable, performant interfaces and services on Vercel and AWS. Own features end to end: UI, API contract, tests, rollout, and post-launch metrics. Build and maintain reusable front-end components, design-system tokens, shared packages/SDKs, and monorepo libraries that multiple apps depend on. Ship commerce and cross-surface UX (identity, entitlements, navigation, checkout/offers) that feels continuous across products. Make accessibility (a11y), internationalization (i18n), and localization part of how you ship, not a follow-up. Ship behind feature flags with instrumentation in place, and use the data to decide what to keep, fix, or cut. Prototype quickly with Product and Design when a working demo settles a debate faster than a document. Use AI-assisted development tools (Cursor, Claude Code, LLM workflows) to raise throughput, and share what works. Write meaningful tests across the stack: Playwright, Vitest or Jest, React Testing Library, visual regression (Chromatic), and Pytest where you touch backend; keep CI trustworthy. Maintain Storybook (and Chromatic) for components and interaction specs; use Tailwind alongside the design system. Participate in sprint planning, retros, and product strategy; raise scope and sequencing concerns early. Mentor through code review and pairing; raise the bar on structure, testing, contracts, and docs. Requirements 5+ years of professional fullstack development, with strong TypeScript, React, Next.js, and Vercel, plus solid backend experience (Python/FastAPI or equivalent) and cloud (AWS preferred). Experience owning or co-owning API contracts between UI and backend, ideally GraphQL (schema, codegen/typed clients, compatibility). Strong grasp of architectural patterns, API design, and performance tuning, plus the judgment to keep solutions simple. Track record of owning features end to end in production, including monitoring, debugging, and iterating on real user behavior. Solid front-end fundamentals: responsive UI, accessibility (a11y), internationalization (i18n), localization, and performance. Experience with design systems: tokens, shared packages/SD