Mobile Architecture: Engineered a cross-platform mobile marketplace using React Native (Expo) and Redux Toolkit, connecting users with verified local service providers within a 5km radius via OpenStreetMap integrations. Auth Modernization: Secured user access and multi-tenant session management by implementing a seamless Supabase Email OTP authentication flow, intentionally deprecating legacy SMS dependencies to eliminate external API latency and costs. Geospatial Engine: Designed a multi-sided PostgreSQL schema leveraging PostGIS spatial queries (ST DWithin) for high-performance geolocation matchmaking, synchronized across client devices using Supabase Realtime channels. FinTech & State Logic: Architected a state-machine booking engine featuring a secure Doorstep PIN handshake for job verification, KYC image capture pipelines, and native UPI deep-linking for frictionless peer-to-peer payments.