Multi Vendor E-commerce Marketplace Development

We're building a curated UAE fashion marketplace connecting shoppers with independent UAE-based fashion brands (think Farfetch/Ounass, but hyper-local). The platform uses a pickup-on-demand model — brands hold their own stock and a courier collects on order, no central warehouse — with a commission-based revenue structure. It's built on Next.js (App Router), TypeScript, Prisma, Supabase, Stripe, and NextAuth, and is roughly 70-80% complete: core marketplace flows (browsing, checkout, brand onboarding, admin dashboard, courier dispatch, returns) are built and functional, and we're now in pre-launch hardening — polishing edge cases, fixing gaps, and preparing for a multi-emirate UAE launch. We're looking for an experienced full-stack freelancer comfortable picking up an existing, well-documented codebase and shipping production-quality work without breaking what's already working. NDA required before repo access.