ABHISHEK VISHWAKARMA

ReWear – Pre-Loved Fashion Marketplace  |  Live: rewear-dusky.vercel.app

• Delivered end-to-end AI integration with a hybrid architecture — text messages routed to Groq (LLaMA 3.1) for 14,400 req/day free-tier capacity, image uploads routed to Google Gemini for vision-based resale price estimation with Cloudinary image input; engineered fault-tolerant 3-key rotation and 2-model fallback chain per provider for production-grade quota resilience across both APIs.
• Built a production-grade real-time MERN + Socket.io application with role-based route protection across 2 roles (Admin, User) — single User account supporting both buying and selling — with bidirectional chat and Cloudinary media uploads via upload_stream pipeline.
• Architected an in-chat price negotiation engine with structured offer/counter-offer/decline flows (2-round limit) persisted across 5 message types using atomic MongoDB operations — eliminating inconsistent transaction states.
• Integrated Razorpay with HMAC server-side signature verification guarding 2 checkout flows (standard + negotiated price) against race conditions; implemented CI pipelines using GitHub Actions and integrated platform-native CD via Vercel and Render — achieving zero hard-refresh failures in production.
• Implemented a 5-status listing lifecycle (pending → approved → rejected → sold → inactive) with admin moderation as a content trust layer; secured Socket.io connections via JWT handshake middleware — rejecting unauthenticated connections before room entry.

Job Portal – Full-Stack MERN Application  |  Live: jobportal-frontend-ten.vercel.app

• Architected a scalable Job Portal (MERN) with RBAC across 2 roles (Recruiter, Job Seeker) — 15+ RESTful APIs on MVC architecture covering job posting, applications, and user workflows with JWT-based authentication and protected routes.
• Built secure backend services with dynamic job filtering across multiple parameters and complete application lifecycle management, following REST principles and clean separation of concerns.
• Integrated Cloudinary for cloud-based resume storage with Multer validation and error handling; delivered a performance-optimized React frontend with code-splitting, dynamic routing, and a fully responsive UI.
• Tested and validated 15+ APIs using Postman ensuring reliable request/response handling and robust error handling across both user roles; configured automated build validation and deployment workflows on Vercel ensuring production stability through environment-based configuration.