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I build AI-powered SaaS products, MVPs, and custom web applications for startups and businesses. 7+ years of experience with React, Next.js, Node.js, Python, PostgreSQL, and AI integrations. 200+ project successfully completed. AI SaaS Developer | Full-Stack Engineer specializing in AI Agents, OpenAI, Claude, RAG, React, Next.js, Node.js, Python, and Startup MVPs. I help founders launch scalable AI-powered products, SaaS platforms, and mobile apps from idea to production. I help startups and SaaS companies ship AI-powered mobile apps and full-stack MVPs, fast, clean, and production-ready. 3 apps launched with 5★ ratings and 50K+ combined downloads; now bringing the same execution standard to AI integration, LLM-powered products, and SaaS platforms. ━━━━━━━━━━━━━━━━━━━━━━ AI & Automation Services : - AI chatbot & agent development (LangChain, OpenAI API, RAG pipelines) - LLM integration into existing SaaS and web apps - AI workflow automation with n8n and Python - Custom GPT tools, voice AI, and document AI - Multi-agent systems (CrewAI, AutoGen) ━━━━━━━━━━━━━━━━━━━━━━ Mobile App Development : - React Native (iOS + Android) — single codebase, 40% cost saving - MVP to App Store launch in 4–6 weeks - FinTech budgeting app: 15K downloads, 4.9★ rating - Health tracking app: React Native + Node.js backend - E-commerce app: Stripe + Shopify API integration - App Store & Play Store publishing included ━━━━━━━━━━━━━━━━━━━━━━ Full-Stack & SaaS MVP : - React, Next.js, Node.js, Laravel, Python (FastAPI/Flask) - SaaS architecture, subscription billing, multi-tenancy - REST & GraphQL APIs, Firebase, PostgreSQL, MongoDB - AWS, Docker, scalable backend deployment ━━━━━━━━━━━━━━━━━━━━━━ Best fit for: → Startup founders building an AI-powered product or mobile MVP → SaaS companies adding AI features or a mobile companion app → Businesses automating workflows with AI agents and LLMs → Teams needing a senior dev who owns the full product cycle UK-based. Available for long-term contracts and dedicated engagements. Let's build something worth shipping. Invite me to your project. Thanks, Sarpreet Tags : AI Integration | AI Chatbot Development | OpenAI API Integration | LangChain Developer | RAG Pipeline Development | LLM Engineer | AI Agent Developer | Generative AI Developer | AI Workflow Automation | n8n Automation | AI SaaS Development | Autonomous AI Agent | Custom GPT Development | AI Automation Expert | Voice AI Agent | Multi-Agent Systems | Full Stack Developer | React Native Developer | Mobile App Developer | SaaS MVP Developer | MVP Development Next.js Developer | Node.js Developer | Python Developer | FastAPI Developer | REST API Development | TypeScript Developer | iOS Android Developer | SaaS Backend Developer | API Integration Expert | React Developer | Shopify API Developer | GraphQL Developer | MongoDB Developer | Laravel PHP Developer | Expo React Native | Push Notifications | Frontend Developer | Backend Developer | NLP Engineer | AI Copilot Development Document AI | Agent | SaaS, PHP, React, Node.js, Claude, ChatGPT API, MERN Stack, React, Next.js, Node.js, NestJS, ExpressJS, React Native, TypeScript, JavaScript, MongoDB, MySQL, PostgreSQL, Supabase, OpenAI API, AI Development, Node.js, RESTful API, ChatGPT API, DALL-E API, OpenAI API, GPT-4 API, AI Model Integration, Java, JavaScript #AIDeveloper #AISaaS #GenerativeAI #OpenAI #ClaudeAI #AIAgents #RAG #LangChain #LLM #AIAutomation #MCP #PythonDeveloper #FastAPI #NextJS #ReactJS #NodeJS #ReactNative #MobileAppDevelopment #SaaSDevelopment #MVPDevelopment #FullStackDeveloper #APIIntegration #AWS #StartupDevelopment #SoftwareEngineer #fullstack

🕰️ 𝐀𝐯𝐚𝐢𝐥𝐚𝐛𝐥𝐞 𝐢𝐧 𝐭𝐡𝐞 𝐔𝐒, 𝐂𝐚𝐧𝐚𝐝𝐚, 𝐔𝐊, 𝐀𝐮𝐬𝐭𝐫𝐚𝐥𝐢𝐚, 𝐨𝐫 𝐩𝐫𝐞𝐟𝐞𝐫𝐫𝐞𝐝 𝐭𝐢𝐦𝐞 𝐳𝐨𝐧𝐞𝐬 🏆 Top-Rated (𝐓𝐨𝐩 𝟑% 𝐨𝐧 𝐔𝐩𝐰𝐨𝐫𝐤) 🌟 10+ Years of Experience ✔ 90+ Successful Projects 📞 Availability: 40+ hours per week If your web app feels slow, breaks under pressure, or can’t scale with growth, I build systems that solve those problems. As a 𝐅𝐮𝐥𝐥 𝐒𝐭𝐚𝐜𝐤 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐞𝐫, I turn ideas into fast, scalable, production-ready MERN applications built for real users and real revenue. With 𝟗𝟎+ completed jobs, and 𝟏𝟎𝟎% Job Success, I focus on building systems that are not just functional, I don’t deliver quick fixes or messy solutions. I build production-ready applications that teams can confidently maintain and scale. 𝐇𝐨𝐰 𝐈 𝐇𝐞𝐥𝐩 𝐘𝐨𝐮: You don’t just need a developer, you need a Full Stack Developer who understands both business and technology. I build end to end MERN applications designed to: • Handle real traffic without performance issues • Scale as your business grows • Stay clean, maintainable, and easy to extend • Deliver real business outcomes, not just features Whether you're launching an MVP, scaling a SaaS, or fixing a broken app, I focus on long term reliability, not quick fixes. 𝐅𝐮𝐥𝐥 𝐒𝐭𝐚𝐜𝐤 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐒𝐞𝐫𝐯𝐢𝐜𝐞𝐬: • 𝐅𝐫𝐨𝐧𝐭𝐞𝐧𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 React.js, Next.js, Redux Toolkit, Tailwind CSS, Material UI • 𝐁𝐚𝐜𝐤𝐞𝐧𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 Node.js, Express.js, REST and GraphQL APIs, TypeScript, Supabase (Auth, Realtime, Edge Functions) • 𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞 𝐚𝐧𝐝 𝐀𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐞 MongoDB including schema design, indexing, and optimization • 𝐀𝐮𝐭𝐡𝐞𝐧𝐭𝐢𝐜𝐚𝐭𝐢𝐨𝐧 𝐚𝐧𝐝 𝐒𝐞𝐜𝐮𝐫𝐢𝐭𝐲 JWT, OAuth2 (Role based access control) • 𝐃𝐞𝐯𝐎𝐩𝐬 𝐚𝐧𝐝 𝐏𝐞𝐫𝐟𝐨𝐫𝐦𝐚𝐧𝐜𝐞 Docker, CI CD, AWS, GCP deployments, SSR, caching, Netlify, Vercel, code splitting, API optimization 𝐏𝐫𝐨𝐯𝐞𝐧 𝐑𝐞𝐬𝐮𝐥𝐭𝐬: • Completed 88 plus projects with 100 percent Job Success • Built SaaS platforms used by real paying customers • Developed CRMs and automation tools that reduced operational costs • Improved application performance with faster load times and better scalability • Delivered clean, production ready code consistently 𝐖𝐡𝐲 𝐂𝐥𝐢𝐞𝐧𝐭𝐬 𝐂𝐡𝐨𝐨𝐬𝐞 𝐌𝐞: • I take full ownership, no micromanagement needed • Clean and well structured code your team can rely on • Clear communication and regular updates • Focus on long term success, not short term fixes 𝐖𝐡𝐚𝐭 𝐈 𝐃𝐨 𝐁𝐞𝐬𝐭: • Full Stack Web Development • MERN Stack Application Development • SaaS Platforms & Dashboards • CRM & Internal Tools • API Development & Integration • Performance Optimization • Scalable System Architecture • Fixing slow or unstable applications 𝐋𝐞𝐭’𝐬 𝐖𝐨𝐫𝐤 𝐓𝐨𝐠𝐞𝐭𝐡𝐞𝐫: If you need a Full Stack developer who understands both business and technology, click Message or Invite and let’s discuss your project. 🔑 Keywords: Full Stack Developer | MERN Stack Developer | Senior Full Stack Developer | React Developer | Node js Developer | Full Stack Developer MERN | Next js Developer | MongoDB Developer | Expert Full Stack Developer | Express js Developer | GraphQL Developer | Full Stack Developer SaaS | Backend Developer | TypeScript Developer | Full Stack Developer React Node | Angular Developer | PostgreSQL Developer | Full Stack Developer API | Web Application Developer | Cloud Developer | Full Stack Developer MongoDB | DevOps Developer | REST API Developer | Full Stack Developer Azure | Docker Developer | CI CD Developer | Full Stack Developer UI UX | JavaScript Developer | Full Stack Developer MVP | Frontend Developer | WebSocket Developer | Full Stack Developer Clean Code | SaaS Developer | Full Stack Developer Scalable | API Developer | Full Stack Developer Bootstrap | MUI Developer | Full Stack Developer Docker | Tailwind Developer | Full Stack Developer WebSocket | UI UX Full Stack Developer | AI | OpenAI | API integration

I am a certified SAP Generative AI Developer with over 18 years of total experience. I hold a degree in Computer Engineering and have expertise in the following areas: 1) SAP Workflow 2) ABAP Web dynpro & CRM 3) Reports (Classical ,Interactive & ALV Report), 4) Smart forms, SAP Script, Print Workbench 5) Object Oriented ABAP, OOALV, 6) BDC (Call Transaction, Session Method),LSMW, 7) Module Pool Programming. 8) ABAP DDIC. 9) IDOC 10) SAP Solman & Charm 11) SAP ISU 12) Artificial Intelligence 13) Python 14) HTML5 15) CSS3 16) NodeJS 17) JavaScript 18) Microsoft Dynamics 365 19) R Language 20) Machine Learning 21) SAP Data Intelligence 22)SAP PI/PO 23) Shopify 24) Blockchain Development in Solidity & JavaScript 25) Google Cloud 26) BigQuery 27) Vertex AI 28) Google Dataflow 29) SAP Analytics Cloud 30) SAP Fiori/UI5 31) Neptune Software for SAP Edition 32) SAP SuccessFactors Employee Central 33) SAP HCM & SuccessFactors Integration 34) SAP Business AI, Generative AI

Expert in Full Stack Development Transform Your Vision into Scalable, High-Performance Applications Looking to build a cutting-edge web or mobile application? I specialize in MERN Stack Development, AI Integration, and Mobile App Solutions that deliver measurable business results. 𝗣𝗿𝗼𝘃𝗲𝗻 𝗦𝘂𝗰𝗰𝗲𝘀𝘀: - Scaled a web application from 1,000 to over 30,000 active users. - Designed subscription systems that handled millions of transactions. - Delivered AI-driven platforms that enhanced automation and business intelligence. 𝗪𝗵𝗮𝘁 𝗜 𝗖𝗮𝗻 𝗗𝗼 𝗳𝗼𝗿 𝗬𝗼𝘂: - Build robust web applications that scale effortlessly, supporting growth from hundreds to thousands of users. - Develop AI-powered tools to streamline operations and improve efficiency. - Create mobile apps for iOS and Android with seamless functionality and user-friendly designs. - Architect SaaS platforms that process millions of transactions smoothly. Technical Expertise: ➡️ Frontend: React.js, Next.js, Tailwind CSS ➡️ Backend: Node.js, Express.js, Django, Flask ➡️ Mobile: React Native, Swift, Kotlin ➡️ AI: ChatGPT integration, intelligent automation ➡️ Database: MongoDB, PostgreSQL, Firebase ➡️ Cloud: AWS, Google Cloud Industries Served: I’ve helped clients in e-commerce, finance, education, real estate, and more. Let’s discuss how I can help your business thrive with tailored solutions that deliver real impact. Please use the following keywords to find me: Full Stack Developer, MERN Stack Developer, React Developer, Node.js Developer, MongoDB Developer, Express.js Developer, JavaScript Developer, TypeScript Developer, React.js, Node.js, MongoDB, Express.js, RESTful API Developer, GraphQL Developer, Backend Developer, Frontend Developer, Mobile App Developer, Flutter Developer, Flutter Expert, Dart Developer, Cross-Platform Mobile Development, Hybrid Mobile Apps, Android Development, iOS App Development, App Development, App UI/UX Design, App Prototyping, Native App Development, Mobile App Development, Mobile Application Development, App Store Optimization (ASO), API Integration, PHP Developer, PHP Web Development, Laravel Developer, WordPress Development, Custom PHP Solutions, Web Development, Responsive Web Design, PHP Frameworks, MySQL, PostgreSQL, AWS, Cloud Computing, AWS Developer, Amazon Web Services (AWS), Firebase Integration, Payment Gateway Integration, Serverless Architecture, Microservices Architecture, Database Design, Web API Development, App Performance Optimization, Push Notification Integration, App Deployment, App Updates, Mobile App Testing, API Security, OAuth, JWT Authentication, Continuous Integration (CI/CD), DevOps, Git & GitHub, Docker, Kubernetes, Agile Development, Jira & Trello, Unit Testing, Quality Assurance (QA), Version Control, Cross-Platform Solutions, Mobile App UX/UI Design, Web Application Security, App Maintenance, App Customization, Web Application Optimization, Web Performance Optimization, Code Reviews, E-commerce Web Development, SaaS Development, SEO for Apps, App Consulting, App Architecture, Cloud Solutions, Mobile App Consulting, App Analytics Integration, App Cloud Integration, Push Notifications, Firebase Cloud Messaging, In-App Purchases (IAP), Single Page Applications (SPA), Progressive Web Apps (PWA), WebSocket Development, Mobile Game Development, UX/UI Prototyping, Mobile App Debugging, App Wireframing, Serverless App Development, CI/CD Pipeline Setup, App Performance Testing, AI, ChatGPT, Artificial Intelligence, Blockchain.

$700K+ delivered on Upwork across 145 projects with a 100% Job Success Score. I architect and ship production AI systems, Voice AI agents handling live calls under 2-second latency, computer vision platforms processing 8M+ daily events, and full-stack products running in production for years. What I build: 𝗩𝗼𝗶𝗰𝗲 𝗔𝗜 & 𝗖𝗼𝗻𝘃𝗲𝗿𝘀𝗮𝘁𝗶𝗼𝗻𝗮𝗹 𝗔𝗴𝗲𝗻𝘁𝘀 Real-time voice pipelines combining speech-to-text, LLM reasoning, and natural voice synthesis. I built SloanConnect, an AI telephony platform that automates insurance verification calls end-to-end, navigates IVR systems, holds dynamic conversations with representatives, and scales to hundreds of concurrent calls. Sub-2-second response time, encrypted compliance handling, production-stable. 𝗖𝗼𝗺𝗽𝘂𝘁𝗲𝗿 𝗩𝗶𝘀𝗶𝗼𝗻 𝗮𝘁 𝗦𝗰𝗮𝗹𝗲 Lead AI Engineer on two production CV platforms: Adlytic - privacy-safe in-store retail analytics with GDPR-compliant pipelines, heatmaps, and POS integration, and SportsEye - real-time soccer analytics from broadcast feeds with 96% accuracy across player tracking, field mapping, and tactical metrics with zero on-field hardware. 𝗠𝗮𝗰𝗵𝗶𝗻𝗲 𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴 𝗦𝘆𝘀𝘁𝗲𝗺𝘀 Hybrid recommendation engines on PySpark processing 8M+ daily impressions. NLP and sentiment systems wired into live dashboards. Healthcare process automation with HIPAA-aligned data handling. Models built to live in real environments, not notebooks. 𝗔𝗴𝗲𝗻𝘁𝗶𝗰 𝗟𝗟𝗠 𝗪𝗼𝗿𝗸𝗳𝗹𝗼𝘄𝘀 (𝗖𝗹𝗮𝘂𝗱𝗲, 𝗢𝗽𝗲𝗻𝗔𝗜, 𝗺𝘂𝗹𝘁𝗶-𝗺𝗼𝗱𝗲𝗹) End-to-end AI agents shipped to production: a Shopify + Amazon SP-API customer service agent with order lookup, refunds, returnless-refund policies, Slack/Email approval gates, and Klaviyo sync. Multi-step LLM pipelines with tool use, RAG, function calling, and human-in-the-loop checkpoints. I design these as systems, not single prompts, and I'm comfortable across Claude, OpenAI, and open-weight models depending on what fits the workload. 𝗙𝘂𝗹𝗹-𝗦𝘁𝗮𝗰𝗸 𝗙𝗼𝘂𝗻𝗱𝗮𝘁𝗶𝗼𝗻𝘀 Every AI product needs scaffolding that holds. I've shipped Django/Node/React/Next.js platforms that ran 3+ years in production, Alchemist Real Estate, audIT.app, and a long-running B2B SaaS that grew from MVP to hundreds of users across $195K+ in contracted development. Distributed backends, REST/GraphQL APIs, AWS-native deployment, data pipelines, and the DevOps to keep them stable. 𝗛𝗼𝘄 𝗜 𝘄𝗼𝗿𝗸 As Lead Engineering Architect, I stay hands-on through the whole lifecycle, discovery, architecture, core implementation, deployment, and the long tail. I don't hand off and disappear. Most of my Upwork work is repeat business or long contracts measured in years, not weeks. If you're building a Voice AI agent, a computer vision platform, an LLM-driven workflow, or a full-stack AI product that needs to survive real load - let's talk.

Need an expert developer or consultant to develop API end points and integrate your heterogeneous platforms on the right foot with large scaled, standard and secured way? I've worked with over 50 USA/UK/Canada/Australia based companies in planning, designing and developing APIs for heterogeneous platforms in a way that fits your business. Whether it's customizing existing API or web application with features that align with your business processes and goals or recommending third-party API/apps to help bridge that gap, I have a true passion for delivering the right mix! Beside API developer, I'm certified web and enterprise application developer for last 10 years which greatly help me to face challenges and provide efficient solutions on complex business requirement. Keeping your business data secured and confidential is my first priority. List of certificates from international vendors: - PHP Certified Developer (zend.com/en/yellow-pages/ZEND011275) - Java Core Developer ( Certified by ORACLE) - Java EJB Developer Expert ( Certified by ORACLE) - Java Web Service Developer Expert ( Certified by ORACLE)