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I am Front-end developer specialized in React.js ecosystem. Experienced in developing and designing SPA's, react native apps, landing pages. I have a working experience with MVC. Technology i use: # React.js React Native # HTML /CSS/JS # Gatsby.js, Next.js # Node, Express # Rest API # Php, Yii2, Laravel # MySql, MongoDB, Firebase # Shopify # WordPress # MVC # Design (Photoshop, Illustrator etc.) I like to work on new projects, help client's achieve their goals, support and optimize already existing projects. My primary goal in initial contact with client is to establish communication and understand his needs.

Senior AI & Full-Stack Developer with 8+ years of experience shipping production web applications across SaaS, healthcare, real estate, and e-commerce. I build AI-powered products with LangChain, LangGraph, OpenAI, and RAG pipelines that handle thousands of queries daily and the full-stack React, Node.js, and Python platforms around them. I work best with founders and teams who need one full-stack developer who can own the whole thing: backend, frontend, AI integration, cloud deployment, and the technical architecture decisions in between. No handoffs, no "that's not my part." ━━ WHAT I CAN HELP YOU WITH ━━ - AI integration & LLM development: RAG search, AI chatbots, AI agents, AI multi-agent platforms, document Q&A, recommendation engines, semantic search, LangChain workflows, OpenAI and Anthropic Claude API integrations - SaaS development: multi-tenant architecture, Stripe subscription billing, RBAC, real-time dashboards, full React + Node.js or Next.js and FastAPI stacks - Scaling & rescue projects: performance optimization, refactors, cloud migration to AWS or GCP, technical debt cleanup, microservices architecture - HIPAA-compliant healthcare apps: telemedicine platforms, patient portals, secure data handling, audit trails - Marketplaces, booking systems, property portals (PropTech), and e-commerce stores with Stripe payment integrations ━━ SELECTED PROJECTS ━━ Pirn.ai: AI Blood Test Recommendation Engine (HealthTech / AI) Built an AI-powered platform that recommends personalized blood tests and generates patient health reports from symptoms. Used by major diagnostic labs in Sweden. OpenAI, LangChain, RAG pipelines, and vector databases tuned for medical-grade reliability. AttendAnywhere: NHS Telemedicine Platform (MedTech) Contributed to a HIPAA-compliant video conferencing application used by the UK's NHS. Focus areas: scalable architecture, low-latency real-time video, and patient privacy at national scale. Numastays: Property Booking & Self Check-In (PropTech / SaaS) Rebuilt the booking flow and user journey for a large rental platform. Delivered multi-property booking, self check-in/check-out, and real-time availability — with measurable gains in conversion and operational efficiency. CheckView: AI-Powered E2E Testing SaaS Platform (SaaS / AI) Built an end-to-end testing platform with AI test planning, AI test generation, and self-healing tests that adapt when UI selectors change. Includes an AI-powered test step generator, scheduled cron job execution, public developer API, and Stripe subscription billing across monthly and annual plans. Works on WordPress and custom sites. ━━ TECH STACK ━━ AI & LLMs: LangChain, LangGraph, LlamaIndex, OpenAI API, Anthropic Claude API, RAG pipelines, vector databases (Pinecone, Chroma, pgvector), embeddings, semantic search, AI agents, prompt engineering, AI chatbot development Frontend: React, Next.js (App Router, Server Components), Vue.js, TypeScript, JavaScript, Tailwind CSS, shadcn/ui, Material UI, Redux Backend: Node.js, Nest.js, Python, FastAPI, Django, REST API, GraphQL, tRPC, PostgreSQL, MongoDB, Redis, Prisma, WebSockets, microservices Cloud & DevOps: AWS, GCP, Vercel, Docker, CI/CD, GitHub Actions, serverless architecture Integrations & Other: Stripe, Auth0, Firebase, Supabase, JAMstack, NextAuth, HIPAA compliance, multi-tenant architecture, real-time applications, MVP development, technical architecture, performance optimization, API integration, payment gateway integration, responsive design ━━ HOW I WORK ━━ I ask questions before I write code. I want to understand what you're actually trying to build and why. that's what separates a project that ships from one that drifts. You'll get clear daily updates, honest timelines, and code that's tested and documented so the next developer on it (you, your team, or a future hire) can pick it up without pain. I'm direct about what's realistic and what isn't. If something won't work, I'll say so early — not three weeks in. ━━ LET'S TALK ━━ If you have a project in mind, send me a message with a short description of what you're building and where you're stuck. I'll reply with honest thoughts on scope, approach, and whether I'm the right fit. Not every project is a match — and I'd rather tell you that upfront than waste your time.

Hi there! I'm a passionate full-stack developer with a strong focus on crafting intuitive, high-performance frontend experiences. With expertise in React and its extensive ecosystem, I specialize in creating pixel-perfect designs that are both functional and visually stunning. Tech Stack Highlights - React: Extensive experience with hooks, context, and state management libraries like Redux and Zustand. - Next.js & Gatsby: Proficient in building performant, SEO-friendly web applications. - Skilled in creating reusable, scalable component libraries for design systems. - Node.js, Express, NestJS: Robust API design and seamless backend integration. - .NET: Comprehensive experience with enterprise-level backend solutions. - Performance Optimization: I ensure applications are lightning-fast and deliver a smooth user experience. - Clean, Maintainable Code: Writing code that’s as easy to understand as it is efficient. - Pixel-Perfect Designs: Collaborating closely with designers to bring ideas to life with precision. I've contributed to a wide range of industries, delivering tailored solutions for: - BIS (Business Information Systems) and DMS (Document Management Systems) - Social platforms that connect and engage users. - Fintech applications designed for secure and efficient financial management. - Travel agency systems that streamline bookings and enhance customer journeys. Whether it’s building a scalable startup solution or improving an in-house system, I thrive on solving complex problems and delivering top-notch results. With experience across startups and established companies, I adapt quickly to any project environment and team dynamic. Let’s collaborate to turn your vision into reality! 💡

I am a Senior Software Engineer and Agentic AI Developer with over 5 years of experience building high-traffic, scalable SaaS platforms for over 3 million active users. I bridge the gap between robust full-stack system design and cutting-edge AI engineering. Whether you are scaling an enterprise frontend, launching a web MVP, or integrating autonomous AI agents into your product, I deliver maintainable, production-ready solutions. My approach combines deep architectural knowledge with modern AI-augmented workflows to drastically reduce development time, eliminate bugs, and align technical output directly with your business goals. 🤖 AGENTIC AI & MODERN ENGINEERING WORKFLOWS I do not just integrate APIs; I build and leverage AI systems to engineer better software. Advanced LLM Orchestration: Specialized in utilizing advanced models—specifically Claude Opus 4.6 and 4.7—which excel at deeply understanding user behavior, mapping complex business requirements, enforcing accessibility standards, and autonomously writing comprehensive test suites. Multi-Agent Development: Structuring custom agentic workflows using the Continue extension within VS Code, driven by precise YAML configurations to automate code generation and refactoring via Sonnet 4.5. Next-Gen Tooling: Fluent in navigating modern development environments, including the Google Anti-gravity IDE, to maintain a highly optimized, AI-first coding pipeline. AI "Coaching" & Context: Adept at prompting and coaching AI models to act as specialized agents that review PRs, generate documentation, and enforce clean architecture. 💻 FULL-STACK SYSTEM DESIGN & FRONTEND ARCHITECTURE I build applications that look beautiful and perform flawlessly under heavy load. Core Stack: Deep expertise in the React.js and Next.js (SSR/SSG) ecosystems, built on strictly typed TypeScript. State & Data Management: Architecting scalable data-fetching and state solutions using Zustand, Redux (Saga/Toolkit), React Query, and GraphQL (Apollo). UI/UX & Styling: Creating pixel-perfect, highly responsive interfaces using Tailwind CSS, SCSS, Radix UI, and custom Storybook component libraries. Progressive Web Apps (PWAs): Building offline-capable applications utilizing Service Workers, IndexedDB, and advanced browser APIs. 📈 MEASURABLE BUSINESS IMPACT & EXPERIENCE Verivox GmbH: Engineered modular React/TypeScript components for a platform serving 3M+ users. Implemented data-driven UI refinements via Optimizely A/B testing, resulting in direct conversion rate increases of 5% to 30% across multiple high-traffic funnels. StackZone & Startups: Rescued stalled product development by introducing strict engineering standards and agile workflows, rapidly eliminating critical bug backlogs. HolidayFox: Spearheaded the ground-up development of a Partner App (V2.0) and Admin Dashboard using Next.js and Tailwind CSS, scaling partner listings by 50% and contributing to a massive 500% increase in Gross Merchandise Value (GMV). Performance Optimization: Redesigned marketplace search and checkout flows using Next.js SSG, drastically improving load times for 800+ listings and reducing customer churn by 30%. 🛠️ TECHNICAL ARSENAL Languages: TypeScript, JavaScript, HTML5, CSS3 Frameworks: React.js, Next.js, Node.js AI/Agentic Tools: Claude Opus 4.6/4.7, Sonnet 4.5, Continue Extension, Google Anti-gravity, GitHub Copilot PDF State/Data: Redux, Zustand, React Query, Apollo GraphQL, REST APIs Styling: Tailwind CSS, PostCSS, SASS, LESS, Ant Design, Bootstrap Infrastructure & Project Management: AWS (Certified Cloud Practitioner), Docker, ClickUp, Git, Jest, React Testing Library If you need an engineer who understands both the rigorous demands of enterprise frontend architecture and the transformative power of agentic AI, let's talk. Send me a message or click "Invite to Job" to discuss how we can accelerate your next project.

🎁 A 100% refund if I set the wrong expectation and can’t deliver. No questions asked! 🏅 Upwork certified Full Stack Developer 🏆 Top Rated (Among Top 10% talent on Upwork) 📈 150M+ Active users on my developed Web Apps 💎 8+ Years of Hands-on Experience ✅ 300+ Websites Designed and Developed ✅ Expert in React/Next.js/Nest.js, Vue.js ✅ Expert in Full-Stack Development MEAN/MERN ✅ Expert in Webflow, Bubble, Retool ✅ Expert in Figma, UI/UX Design & Development ✅ Excellent Communication and Project Management Skills ✅ Custom Rag system, LLMs ✅ Model fine tuning, gpt functions to get exact output. *** Available for RUSH projects *** I have experience with the following industries: 💰 Fintech: Scalable financial platforms with real-time data 🏥 Healthcare: HIPAA-compliant patient management and telemedicine 🚚 Logistics: Real-time tracking and fleet management ✈️ TravelTech: Booking systems and travel management tools 🔐 Cybersecurity: Secure applications and data protection 🌾 Agricultural industry 👩‍⚕️ eCommerce FRONT-END SKILLS HTML 5, CSS 3, JavaScript, TypeScript/ECMAScript, React.js, Nuxt.js, Gatsby.js, Flexbox, SCSS, SaaS, Bootstrap, Tailwind and Material-UI BACK-END SKILLS Node.js, Next.js, PHP, Python, Java, Ruby, Express, RESTful API and GraphQL FRAMEWORKS Gatsby.js, Angular, Express CMS, React, Vue.Js Strapi CMS, ContentStack Version Control System: GitHub, GitLab 𝐂𝐌𝐒: → WordPress, Webflow, Shopify, WooCommerce, Wix, Retool, Bubble.io COMMUNICATION AND SOFTWARE MANAGEMENT TOOLS Slack, Discord, JIRA, Asana, Trello, Monday, Clickup, Zoho and Basecamp ✮ Worked with German unicorn companies ✮ Available 18 hours a day BOOK A 30-MIN CONSULTATION Interested in discussing you project details with me? You are one click away from making the next web solution for your business. Message me and book a 30-Min Consultation Call. I'll be happy to provide you the technical project plan, time estimate and overall cost. ABOUT ME I am a proficient web developer with a strong focus on React and the MERN stack, and a knack for creating seamless user experiences. Leveraging my expertise in building dynamic and responsive web applications, I specialize in crafting high-performance, data-driven solutions. With a keen eye for design and overall user-experience, I seamlessly bridge the gap between aesthetics and functionality, delivering visually appealing, user-friendly web solutions. My skills in front-end and back-end development, combined with my proficiency in React / React Native / Node.js / MongoDB / Express / DevOps / GPT and LLM apps development make me a valuable asset in delivering cutting-edge web solutions. Over the course of my 8+ years of professional experience, my enthusiasm for technology and programming has only grown, driving me to solve complex technical challenges and come up with innovative solutions. 𝐍𝐨𝐭 𝐭𝐡𝐞 𝐑𝐢𝐠𝐡𝐭 𝐅𝐢𝐭 𝐈𝐟: ❌ Your business operates in industries like betting or adult entertainment. ❌ You don’t value open communication and collaboration throughout the development process. ❌ Mutual respect is not important to you in a working relationship. 𝐅𝐢𝐧𝐝 𝐦𝐞 𝐰𝐢𝐭𝐡 𝐭𝐡𝐞 𝐤𝐞𝐲 𝐰𝐨𝐫𝐝𝐬 𝐛𝐞𝐥𝐨𝐰: API, RESTful API, API Integration, AWS Lambda, Amazon Web Services, Docker, Git, Agile Software Development, Python, JavaScript, ECMAScript, TypeScript, jQuery, AngularJS, React, Redux, Next.js, ExpressJS, Node.js, Prisma, PostgreSQL, SQL, CSS, CSS3, Sass, Tailwind CSS, HTML, HTML5, Template Markup, Mobile App Development, React Native, iOS, iOS Development, Android, Android App Development, Web Development, Web Application, Website, Web Design, Graphic Design, UI/UX Prototyping, User Authentication, Search Engine Optimization, Social Media Account Integration, Chat & Messaging Software, Twilio API, Expo.io, Landing Page, comfy, polotno, Artificial Intelligence.

Hi! I am Manuel, an Information Systems Graduate, Web developer and passionate E-Commerce-Manager. I offer you a wide range of professional services related to E-Commerce, like building and taking care of websites or online-shops, developing and implementing online marketing campaigns and integrate any other digital sales channel into your business. Since I've started in 2016, I have built 15+ successful running websites and profitable online shops. Most of them I still maintain for my clients today. I want to share my knowledge with you, and I am happy when I can help! Just ask me!