Full-Stack Developer (BeejQR — Seed Verification SaaS Platform)
Freelance / Serving 3 Active Seed Manufacturing Enterprises
Project · Jan 2025 - Present
Project Details
- Architected a multi-tenant B2B AgriTech SaaS platform serving 3 active seed manufacturing companies with strict company-level data isolation, custom branding, and RBAC (OWNER / SUPER_ADMIN).
- Built an atomic credit deduction wallet (500 credits/QR) using database transactions to guarantee zero double-spending under concurrent QR generation requests.
- Integrated Razorpay payment gateway with HMAC webhook signature verification, automated invoice generation, and idempotent transaction logging.
- Developed a mobile-first public verification page (/p/:code) with <1s load time, authentic certification badge, and tri-lingual i18n support (English, Hindi, Gujarati).
- Designed a normalized 19-model PostgreSQL schema and 13 RESTful API controllers with Zod schema validation, Pino structured logging, Helmet security headers, and Swagger/OpenAPI documentation.
- Implemented dual JWT authentication (15-min access + 7-day refresh tokens) with secure rotation and route-level role authorization guards.
- Built a real-time scan telemetry pipeline capturing device fingerprints and geography, with AWS S3 asset storage and AWS SQS for asynchronous background tasks.