Jahanzaib I.

Upwork Top Rated Plus | Full Stack Developer — React, Next.js, Node.js I build production-ready SaaS applications with React, Next.js, and Node.js — including AI features using OpenAI, Claude, and LangChain that actually work with real users, real data, and real production constraints. I don't just connect an LLM to an existing app and call it "AI." I focus on building AI features that are reliable, tested, and maintainable by a real engineering team. What I've built AI Voice Automation Platform — PropTech - Built an AI-powered voice automation system for apartment leasing - Real-time speech processing with Twilio, Node.js, NestJS, and OpenAI - LLM-based call scoring and semantic search across call history - Improved call answer rate from roughly 50% to 95% - Platform has contributed approximately $1M in business revenue Production Admin Platform — Medical Technology - Built and maintained a high-traffic platform for an FDA-cleared medical device ecosystem - React + Node.js + PostgreSQL architecture - Automated workflows across super admin, sub-admin, and patient roles - Product capabilities were cited by investors during the company's $5M funding round AI Legal Intake & Document Processing - Built an AI-assisted legal intake workflow to reduce manual data entry - Automated OCR, document processing, data extraction, and workflow automation Legal Operations Integrations - Built a two-way integration between HubSpot, Litify, and Filevine - Synced 1,000+ records, saved the team 10+ hours per week - Reduced manual data entry by 90%+ and duplicate/data-entry errors by 95%+ Core Technical Stack Frontend-Development: React, Next.js, TypeScript, Vue.js, Nuxt.js, Angular Backend-Development: Node.js, NestJS, Express.js, Python, FastAPI, REST APIs, GraphQL Databases: PostgreSQL, MongoDB, MySQL, Redis Cloud & Infrastructure: AWS, GCP, Docker, Kubernetes, CI/CD AI: OpenAI API, Claude API, Gemini API, LangChain, RAG, vector search, embeddings, function calling, AI agents How I approach projects Before writing code, I look at where the system is likely to break: data model limitations, API dependencies, scalability, failure handling, background processing, AI reliability, and integration edge cases. I use AI development tools to move faster, but I don't outsource engineering judgment to them I review architecture, validate generated code, write tests, and make sure the final system is maintainable. Whether you're building a new AI-powered SaaS product, adding AI to an existing application, developing a scalable React/Next.js + Node.js app, building complex API/CRM integrations, or scaling an existing production system tell me what you're building or where you're stuck, and I'll give you a straightforward technical assessment and a practical path forward.