Harmanpreet K.

Full-Stack Developer|React, Next.js, Node.js, SaaS & AI App|Vibe Coder

Senior Full-Stack Developer with 10+ years of experience building SaaS platforms, AI-powered applications, and scalable web products using React.js, Next.js, Node.js, and TypeScript. I help startups and businesses launch fast, scalable, and production-ready applications, from MVPs to enterprise-grade SaaS platforms. I build high-performance web apps, SaaS platforms, and AI-powered products 3x faster using modern Vibe Coding workflows, without compromising quality. ✔ 100% Job Success ✔ Top Rated Plus ✔ $100K+ earned on Upwork ✔ 6,600+ hours worked ✔ Long-term client relationships Specialized in: - SaaS Development - AI Integrations (OpenAI/ChatGPT) - Next.js & React Applications - Node.js APIs & Backend Systems - Dashboard & Admin Panels - Multi-tenant Architectures - Stripe & Payment Integrations - AWS & Cloud Deployment Specializing in the MEAN (MongoDB, Express.js, Angular, Node.js) and MERN (MongoDB, Express.js, React, Node.js) stacks, I leverage the latest technologies to create robust, scalable, and performance-driven applications. Here’s what I bring to the table: Tech Stack Expertise ✅ Frontend Development: - React.js, Next.js, Redux Toolkit, Angular - HTML5, CSS3, Tailwind CSS, Material-UI, Bootstrap - TypeScript and JavaScript (ES6+) ✅ Backend Development: - Node.js, NestJS, Express.js - GraphQL, RESTful APIs, Microservices Architecture ✅ Database Management: - MongoDB, PostgreSQL, Firebase, MySQL ✅ AI and Machine Learning Integrations: - OpenAI APIs (ChatGPT, GPT-4), AI/ML-powered applications AI & LLM Skills: OpenAI API — GPT-4, Assistants API, function calling Claude API (Anthropic) & Google Gemini integration AI chatbot development with custom knowledge bases LangChain for building LLM pipelines Vector databases — Pinecone, pgvector, ChromaDB Prompt engineering & embedding models / semantic search ✅ DevOps and Cloud: - AWS (Lambda, EC2, S3), Azure, Docker, Kubernetes ✅ Version Control and CI/CD: - Git, GitHub, GitLab, Bitbucket - Jenkins, GitHub Actions ✅ Testing Tools: - Jest, Mocha, Chai, Cypress ✅ Project Management and Collaboration: - Jira, Trello, Slack, Agile/Scrum methodologies ✅ Industry Experience: Delivered successful projects across diverse industries, including: - E-commerce and Marketplaces - Healthcare and Telemedicine platforms - Finance and FinTech platforms - Education and E-learning platforms - Travel and Hospitality platforms - Real Estate Platforms - Social Networking and Lifestyle Apps - AI-driven SaaS and Automation Solutions Why Choose Me? I am passionate about creating scalable, performance-optimized, and user-centric applications that solve real-world problems. My development process focuses on delivering clean, maintainable code while meeting deadlines and exceeding client expectations. Whether you’re looking to develop a brand-new AI-integrated app, revamp your existing web platform, or build a system from the ground up, I can help turn your vision into reality. Let’s collaborate to build something exceptional. Reach out, and let’s start your project today! -------- Keywords: React developer, Next.js developer, Full-stack developer, Node.js developer, SaaS developer, AI developer, TypeScript developer, API developer, Dashboard developer, MVP developer, Startup developer, Web application developer MEAN Stack Development, MERN Stack Developer, Full Stack Web Applications, API Integration Services, Secure Web Development, Responsive Web Design, Scalable Web Solutions, MongoDB Expertise, Node.js Professional, Angular Development, React Development, WebSocket Implementation, Firebase Integrations, AWS Integrations, Payment Gateway Integration, Performance Optimization, Agile Full Stack Development, Real-time Data Applications, AI Developer, LLM Developer, Generative AI, AI Automation, AI Engineer, Python AI Developer, AI Chatbot Developer, OpenAI Developer, Claude AI, GPT-4, AI Integration, AI Workflow Automation RAG Systems, Retrieval Augmented Generation, Vector Database, Semantic Search, Embedding Models, AI Knowledge Base, Document AI, AI Search System, LangChain RAG, LlamaIndex, Pinecone, ChromaDB, FAISS