Senior Full-Stack Developer Needed For Creative Immersive App

We're building an immersive, browser-based charitable app with 3D environments, Shopify integration, and rich media features. We need an experienced developer who can move fast, make smart decisions, and deliver a polished PWA under real deadline pressure. This is a paid contract with milestone-based payments and a clear, locked scope. THE ROLE Build a React-based progressive web app (PWA) featuring: • 4 x navigable 3D environments using Three.js / React Three Fiber • Shopify Storefront API integration with shopping cart • Embedded media players and e-reader functionality • Clean, performant UI across mobile and desktop • Vercel deployment WHAT WE'RE LOOKING FOR • Proven experience with Three.js or React Three Fiber (please share live examples) • Shopify Storefront API / headless Shopify experience • PWA development and deployment • Strong component architecture and clean handoff documentation • Excellent communicator who flags issues early • Available to start immediately TIMELINE 2 weeks from start. Milestone check-ins throughout. BUDGET Please include your day rate or fixed project rate when applying. TO APPLY Share a link to a live Three.js or React Three Fiber project, your Shopify integration experience, and your availability. A brief note on how you'd approach this stack is very welcome. This is for a charitable project, fast-moving, meaningful work with a team that knows what it wants.