Built NexCart, a multi-tenant SaaS ecommerce website builder for merchants who want their own branded online store — not a marketplace listing. Merchants can register, complete an 8-step onboarding wizard, pick a theme, add products, configure shipping/payments/tax, and publish to a dedicated storefront with custom domain support. What I built: • Full merchant dashboard: catalog (variants, inventory, categories, media), orders, fulfillment, refunds, and store settings • Theme engine + storefront (homepage, PLP, PDP, search, cart, checkout, customer accounts) • Growth suite: SEO, blog, reviews, email campaigns, loyalty, gift cards, and analytics • Multi-tenant architecture with row-level security, publish/rollback, background jobs, and audit logging Stack: Next.js 15, React 19, TypeScript, Tailwind, Supabase (Auth, Postgres, RLS, Edge Functions), Vercel