Uday Kumar

I’m a Computer Science undergraduate focused on Java full-stack development, combining Spring Boot, React, and MySQL to ship end-to-end products. I enjoy turning complex requirements—like authentication, concurrency control, and payments—into reliable features through clean REST APIs.

In my ShopEase project, I engineered a scalable e-commerce platform that handles secure access and dependable checkout flows. I prevented overselling during concurrent purchases with optimistic locking (@Version) and automatic retries (@Retryable), while also eliminating duplicate payment confirmations using Razorpay with HMAC-SHA256 signature verification and pessimistic locking for idempotent processing.

I care about consistency and maintainability, so I standardized API error responses using @RestControllerAdvice to return structured JSON for every failure case. I delivered a complete backend covering products, users, orders, carts, payments, and reviews—supporting browsing, search, filtering, and checkout.

Through internships, I’ve built practical full-stack applications: at InAmigos Foundation, I created a Spring Boot + React + MySQL app for NGO outreach programs and donor information, and at InternPe, I developed a code analyzer that detects syntax and errors to improve debugging workflows. Alongside building software, I’ve strengthened my fundamentals by solving 250+ DSA problems on LeetCode and GeeksforGeeks and qualifying GATE in the first attempt.