Built a full-stack fintech demonstration app with Next.js, TypeScript, and Supabase, connecting wallet interfaces to PostgreSQL data models, authentication, row-level security, and real-time updates.
• Implemented account balances, transaction history, and simulated transaction creation with Supabase Realtime updates and clear loading, error, and optimistic states.
• Applied per-user access policies with PostgreSQL row-level security and Supabase Auth.
• Built responsive interfaces with React, Tailwind CSS, and shadcn/ui, including keyboard navigation and focus states, plus a compact admin view and Expo mobile companion.
• Used strict TypeScript, Jest/React Testing Library tests, linting, and pull-request CI, with setup documentation for local development.
Scope: Portfolio demonstration using test accounts and simulated transactions. No real funds are processed.