Backends that hold under load.

I design and deliver Spring Boot microservices for high-traffic production applications — 10+ so far, carved out of a monolithic codebase so services deploy independently instead of as one unit. I've built and secured 100+ REST endpoints with JWT authentication and role-based authorization using Spring Security, eliminating unauthorized-access defects across all services.

On the payment path I integrated gateway flows handling 100+ monthly transactions, using idempotency keys and webhook reconciliation to prevent duplicate charges and payment mismatches. On the data path I optimize Hibernate/JPA queries and MySQL schemas — resolving N+1 issues, adding composite indexes, and introducing Redis caching for frequently accessed data, measurably reducing average API response time.

I own backend features on two products. For Ekatra, a co-shopping platform, I built the Wix plugin that powers real-time shared shopping sessions, plus session-based event tracking with data processed in MongoDB to drive merchant-facing behavioral analytics. For Annotico, a property investment platform, I developed broker analytics dashboards, dual payment gateway integration (Stripe and Dodo Payments) for subscription billing, and a WhatsApp-based investor notification system.

I developed and maintained Spring Boot REST APIs for a Customer Management System serving 500+ active users, on a clean layered architecture following SOLID principles.

The hardest piece was a real-time property bidding system handling concurrent bids — built on database transactions and explicit locking strategies to guarantee data consistency under simultaneous access. I also implemented payment gateway integration and role-based access control across the core modules, securing sensitive customer and transaction data.

Throughout, I partnered with frontend, QA and product teams in Agile sprints, translating business requirements into scalable, maintainable backend designs.