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Hello! I'm a versatile Full-Stack and AI Developer with 8+ years of experience building scalable, high-performance web applications and intelligent digital solutions. I specialize in both front-end and back-end development, combining modern JavaScript frameworks with Python, cloud infrastructure, and AI technologies to deliver full-fledged products. My tech toolkit includes React.js, Vue.js, Angular, Node.js, Python, FastAPI, MongoDB, PostgreSQL, and a strong command of AWS services, including Lambda, Cognito, Amplify, Generative AI, LLM, Tensorflow, Langchain and more. I’ve also worked on GPT-powered features, integrating AI models to create smarter, more responsive applications. ✅ Services Offered: Front-End Development Responsive, user-centric UI design with React, Vue, and Angular State management using Redux, Vuex, etc. Seamless API integrations (REST & GraphQL) Performance optimization and accessibility best practices Back-End Development Robust API and microservice development using Node.js, Express, and FastAPI Python-based back-end logic for data processing, automation, and API services Secure authentication/authorization systems and custom middleware Database design and optimization (MongoDB, PostgreSQL) Web scraping (scraped sites like EBay for product information with images) AI & GPT Integrations Custom GPT-3.5/GPT-4 integrations for automation, chatbots, and smart UI features Prompt engineering and fine-tuned AI workflows Back-end support for AI features, including caching and input sanitization Data pipelines (from scratch and using individual components, not by using services like databricks or airflow) Machine learning models, their tuning and data analytics (using libraries like Tensorflow, langchain, crewAI, PowerBI) Cloud Services & DevOps AWS Cognito for secure user authentication and identity management AWS Lambda for serverless backend logic and API endpoints AWS Amplify for fast, scalable full-stack deployment and hosting Containerization with Docker and orchestration using Kubernetes CI/CD pipelines for efficient development and delivery Full-Stack Solutions Full end-to-end development with MERN, MEVN, or Python + React stacks Third-party API integrations and real-time features (WebSockets, Pub/Sub) Scalable infrastructure on AWS, including EC2, S3, CloudFront, and RDS 💼 Why Work With Me? Client-Focused: I align my work with your business needs and project goals Results-Oriented: Clean, maintainable, high-performance code every time Reliable Communication: Regular updates, collaborative approach, and full transparency On-Time Delivery: I respect deadlines and take ownership of getting the job done right Let’s turn your ideas into reality. Whether you're building an MVP, enhancing an existing system, or integrating AI-driven features, I’m here to help. Let’s connect and talk about how I can bring value to your next project!

🏆 I led full stack developer work at Bairro, a startup that reached $25M valuation with $7M raised - serving 50K+ users on a React and Node.js platform I architected as lead full stack developer. That full stack developer experience shaped my approach as a website developer who delivers production-ready results. Over 7+ years as a full stack developer I have shipped 50+ projects across SaaS Platform, Web App, Mobile App, and AI-Powered products using React and Node.js. 🚀 As a Senior Full Stack Developer and Full Stack Engineer I cover the full product lifecycle. I started as a web developer and website developer before becoming a full stack developer who handles React frontend and Node.js backend equally well. My full stack developer react node experience means clients work with one Full Stack Web Developer instead of separate teams. Every full stack developer engagement I take begins with React and Node.js architecture planning and ends with a production-ready SaaS Platform or Web App. 👋 Hi! I am Oleksandr, a Full Stack Developer and website developer specializing in scalable SaaS Development and App Development. As a react developer with strong Node.js skills, I build apps where React handles complex UI logic and Node.js manages APIs and real-time services. My Full Stack Developer approach covers SaaS Web App, Marketplace App, MVP SaaS, and Platform Development projects. Whether you need a Developer Needed for a SaaS Product or a Full Stack SaaS Developer for a Management Platform — I deliver. 📱 My full stack developer background spans diverse ecosystems. I work as a full stack developer ai specialist and AI Engineer implementing machine learning and AI Agent features. I deliver full stack developer shopify specialist work, full stack developer laravel builds, python full stack developer projects, and .net full stack developer enterprise solutions. I use wordpress for CMS-driven website developer projects. As a mobile app developer and React Native specialist I build Mobile App Development products for iOS and Android. I also cover Real Estate and Property Management platforms as a full stack developer. 🌐 As a website developer I build everything from landing pages to enterprise platforms. My website developer work includes react next.js node.js backend developer solutions, word press website developer projects, wordpress developer and website design builds, and shopify website developer integrations. I handle wix website developer requests and follow SEO best practices on every website developer project. Every website developer solution uses React for speed and Node.js for backend power. ⚡ React is my primary framework as a Full Stack Developer and Full Stack Web Developer. React powers SaaS Dashboard, Marketplace App, and Management Platform products I build. I pair React with Node.js creating unified JavaScript stacks as a full stack node.js react specialist. React components communicate with Node.js APIs seamlessly in my full stack developer react workflow. Beyond React I use Vue, Angular, and react native for Mobile App Development — but React with Node.js stays my Full Stack Developer core. 🔧 Node.js is my primary backend as a back end developer and node.js backend developer. I build REST APIs, GraphQL, and microservices using Node.js in every Full Stack Developer project. My node.js react pattern handles heavy traffic for SaaS Platform and Web App clients. Node.js powers authentication, payments, real-time messaging, and AI Agent data pipelines in every full stack developer engagement. 📲 As a full stack mobile developer I deliver Mobile App Development using React Native and react native mobile builds. A Full Stack Developer react node architecture spans web and mobile — one Full Stack Developer handles the full App Development lifecycle. My react native work covers SaaS Product, Marketplace App, and Real Estate mobile platforms. 🔗 As a Full Stack Developer and web developer I integrate services across every website developer project. React frontends connect to CMS, e-commerce, and CRM solutions. Node.js services plug into Stripe, Twilio, and dozens of APIs. My website developer and Full Stack Developer solutions deliver production-ready SaaS Development results on time and on budget. ✅ Every website developer and Full Stack Developer project follows clean architecture. React stays modular, Node.js stays documented, deployments run automatically. React and Node.js together are the Full Stack Developer foundation I build on. I validate every Web App and SaaS Platform against real benchmarks. React. Node.js. Full Stack Developer. website developer. React. Node.js. full stack developer. React. Node.js. React. Node.js. full stack developer. website developer. React. Node.js. 🔑 full stack developer. React. Node.js. website developer. React. Node.js. full stack developer. React. Node.js. website developer. full stack developer. React. Node.js. React. Node.js.

Full Stack Developer & AI Developer / SaaS Architect — I'm a Web Application Developer & AI Engineer focused on AI Solutions & SaaS Development. Strong skills as an AI SaaS Developer, Senior Python Developer, and React Developer. Top Rated Plus | 100% Job Success | Only 5-star reviews ⭐⭐⭐⭐⭐ You'll get your AI SaaS prototype in 2 days, your AI-Powered SaaS MVP or AI solution shipped in 6-12 weeks🚀 🎓 BACKGROUND I've Master’s in Data Science & AI, currently preparing a PhD in AI. I’m a Senior Full-Stack Developer / AI Developer & AI Solution Architect with more than 8 years across 60+ projects. 💬 "Ilya led the work as the AI SaaS solutions architect & AI full-stack engineer, taking ownership of the overall architecture and delivery. Ilya delivered as an AI SaaS developer — balancing product, engineering, AI work without losing speed or quality. Ilya was exactly the kind of fractional CTO & engineering partner I was looking for. Highly recommend Ilya" — Jake Kinzelberg, Founder, Insurance AI SaaS, USA 💬 "Thanks to Ilya for developing my AI-powered SaaS. Ilya proved himself as an excellent AI Software developer & fullstack developer, proposed a clean UI UX SaaS Web design, built a solid backend with Python FastAPI, a front end with React" — Dmitri Dalla-Riva, Founder of Aidtrade, Australia 🎯 WHAT I DO I ship production-grade AI SaaS / AI product end-to-end. You come to me when you need: 🔹 SaaS MVP in weeks — built on architecture that scales beyond the prototype 🔹 AI development, AI Integration, LLM integration — RAG pipelines, AI agent SaaS, Voice Agent 🔹 Full Stack development delivery — one senior point of contact, one accountable owner 🔹 A technical co-founder mindset — scoping the SaaS development, making architecture decisions, owning the result 🛠 HOW I WORK As a Senior Full Stack Developer (React Python), AI Architect, I lead a small team — Senior Backend Engineer (Python Node.js), Frontend (React Angular Next.js), Full Stack Developer AI (JavaScript Vue.js jQuery Bootstrap), AI/ML Engineer, Mobile App Developer (Flutter), UI UX designer / SaaS UX designer — all under my direct coordination. In my work as a Full Stack AI SaaS developer & Python developer, I act as your delivery manager: one point of contact, the delivery capacity of a small agency. I work with Founders as a long-term Partner — calm execution, clear communication 📌 AI-Powered SaaS Development As a Full Stack Web Developer / AI SaaS full stack developer / SaaS AI Software Architect, I design SaaS Startup MVP that scale beyond the first version — multi-tenant architecture, role-based access, billing, webhooks, pipelines 🔹 SaaS architecture → Multi-tenant SaaS, RBAC, OAuth2, Stripe, AI API Integration 🔹 SaaS data layer → PostgreSQL, Redis, Supabase, multi-tenant isolation 🔹 SaaS infrastructure → Docker, AWS, Azure, Vercel, Cloudflare, CI/CD 🔹 SaaS delivery & AI MVP Development → SaaS design, MVP-to-production in 6 weeks 📌 AI Software Development As an Anthropic / OpenAI Developer, Data Scientist & Machine Learning Engineer, I integrate LLM & RAG into SaaS & Websites 🔹 AI/LLM integrations → Claude, ChatGPT-5, LLaMA, Mistral — fine-tuning, prompt design 🔹 RAG & Vector DB → LangChain, FAISS, Qdrant, Pinecone, ChromaDB, pgvector — Voyage embeddings, hybrid search inside SaaS, AI SEO 🔹 Generative AI → Stable Diffusion, SDXL, LoRA — custom image pipelines 🔹 AI ML Engineer → AI automation, deep voice agent, Computer Vision, MCP integrations, dashboards, LLM-powered SaaS 📌 Full Stack Development / Web Application Development As an AI Machine learning / Python Full Stack Developer & React developer / Senior Web Developer Python, I own the SaaS product end-to-end — ReactJS Next.js frontends, Python FastAPI Node.js backends with Superbase; MERN stack, PHP, Webflow / WordPress developer. 🔹 Front end developer → React, Next.js, TypeScript, Tailwind CSS, JavaScript 🔹 Backend developer → Python FastAPI, Django, Node.js, REST API development, GraphQL APIs 🔹 Real-time → WebSockets, Server-Sent Events for streaming AI 🔹 Web Application architecture & Web Development → modular monorepos, microservices 🤖 SENIOR AI-AUGMENTED DEVELOPMENT As a Senior AI Engineer / Python Backend Developer, I use modern AI tools for faster AI development: GitHub Copilot for coding, ChatGPT for reasoning, Cursor for refactoring, Claude Code with MCP for architecture, Replit for prototype testing, Lovable for MVPs prototyping, Bolt.new for web app experiments, v0 by Vercel for UI generation 🏆 MY UPWORK TRACK RECORD ✅ Top Rated Plus Expert ✅ 100% Job Success Score ✅ $200K+ earned delivering SaaS & AI Solutions ✅ 16 completed Upwork jobs ✅ 5-star average rating ✅ Upwork Skill Certified — Python Developer; Back-End Development 🤝 LET'S WORK TOGETHER If you're building SaaS or AI solution — you need a technical partner who ships, owns, thinks like a co-founder — message me. You’re taken from idea to deployment — faster and smarter

🚀 Top 1% of Talent in 𝐀𝐈-𝐏𝐨𝐰𝐞𝐫𝐞𝐝 𝐅𝐮𝐥𝐥-𝐒𝐭𝐚𝐜𝐤 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 & Technology Leadership ⚡ Building 𝐀𝐈-𝐩𝐨𝐰𝐞𝐫𝐞𝐝 𝐩𝐫𝐨𝐝𝐮𝐜𝐭𝐬, enterprise platforms, SaaS solutions, and scalable digital ecosystems 🔧 Using modern AI tools including Cursor, Claude Code, GitHub Copilot, GPT-4/GPT-4o, and Claude Sonnet/Opus 🤖 Experienced in AI agents, LLM integrations, AI automation, and multi-agent development systems 🚀 Accelerating development with 𝐀𝐈-𝐚𝐬𝐬𝐢𝐬𝐭𝐞𝐝 𝐞𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢, agentic coding, and automation-driven workflows 💻 𝐖𝐇𝐀𝐓 𝐘𝐎𝐔 𝐀𝐍𝐃 𝐘𝐎𝐔𝐑 𝐓𝐄𝐀𝐌 𝐆𝐄𝐓 Full-Stack Web Development Master's - high-performance web application development utilizing React, Node.js, and PHP to build scalable SaaS, FinTech, and Enterprise software. AI & Automation Systems Innovators - custom LLM applications, RAG pipelines, and intelligent workflow automations seamlessly integrated into your infrastructure. 📊 𝐀𝐂𝐇𝐈𝐄𝐕𝐄𝐌𝐄𝐍𝐓𝐒 𝐈𝐍 𝐍𝐔𝐌𝐁𝐄𝐑𝐒 (𝐁𝐔𝐒𝐈𝐍𝐄𝐒𝐒 & 𝐒𝐘𝐒𝐓𝐄𝐌 𝐈𝐌𝐏𝐀𝐂𝐓) 25+ years, 50,000+ engineering hours, 200+ successful launches delivered as a Senior Full Stack Developer and tech leader across global industries. ◾ Full-Stack Web Development for Enterprise & SaaS Platforms: Engineered and launched custom AI-powered SaaS platforms that scaled to millions of active users with 99.99% operational uptime. Accelerated product development cycles by 40% by deploying optimized React component libraries and agile workflows. Backend Architecture & API Engineering (Node.js & PHP): Reduced server infrastructure costs by 50% by migrating legacy monoliths into scalable microservices using Node.js, NestJS, and PHP. Optimized heavy data-processing pipelines, reducing database latency by 70% via tailored PostgreSQL, MongoDB, and MySQL schemas. ◾ AI App Development & Workflow Automation: Developed and integrated proprietary OpenAI GPT, Claude, and Gemini models into operational CRMs, increasing client workflow efficiency by 180%. Successfully deployed secure, HIPAA-compliant healthcare applications and high-security FinTech platforms with built-in Stripe / PayPal integrations. 🎯 𝐖𝐇𝐄𝐑𝐄 𝐖𝐄 𝐃𝐄𝐋𝐈𝐕𝐄𝐑 (𝐂𝐎𝐑𝐄 𝐄𝐗𝐏𝐄𝐑𝐓𝐈𝐒𝐄) As a Full Stack Developer & Solution Architect: I handle the full cycle of Full-Stack Web Development, defining technical roadmaps, designing scalable web applications, and ensuring bulletproof cyber-security protocols. As a Front-End Development Expert: Crafting pixel-perfect, highly responsive user interfaces using React, Next.js, TypeScript, Vue.js, and Angular to ensure maximum conversion rates and premium UX. As a Back-End Development Authority: Designing ultra-fast APIs and core services with Node.js (Express/NestJS), PHP, Python (FastAPI/Django), and modern Serverless Stack architectures. As a Cloud & DevOps Engineer: Implementing enterprise-grade cloud deployments via AWS, Google Cloud, and Azure, utilizing Docker, Kubernetes, and automated CI/CD pipelines. 🛠 𝐓𝐄𝐂𝐇 𝐒𝐓𝐀𝐂𝐊 & 𝐀𝐑𝐂𝐇𝐈𝐓𝐄𝐂𝐓𝐔𝐑𝐄 𝐄𝐂𝐎𝐒𝐘𝐒𝐓𝐄𝐌 Frontend Suite: React, Next.js, TypeScript, Tailwind CSS, Vue.js, Angular, Responsive Web Design. Backend Core: Node.js, NestJS, Express.js, PHP, Python, FastAPI, Django. Databases & Caching: PostgreSQL, MongoDB, MySQL, Redis. APIs & Global Integrations: REST APIs, GraphQL, Webhooks, Stripe, PayPal, Twilio, SendGrid. Cloud & DevOps Platform: AWS (Amazon Web Services), Google Cloud, Azure, Docker, Kubernetes, Jenkins, GitHub Actions CI/CD. 🧠 𝐃𝐄𝐄𝐏 𝐈𝐍𝐃𝐔𝐒𝐓𝐑𝐘 𝐄𝐗𝐏𝐄𝐑𝐈𝐄𝐍𝐂𝐄 AI & SaaS Startups: Rapid MVP development, RAG pipelines, AI chatbots, and predictive analytics tools. FinTech & E-commerce: High-load payment gateways, customized checkout solutions, compliance, and ledger systems. Healthcare & PropTech: Automated workflow systems, secure patient portals, CRM platforms, and real-time data visualization dashboards. Enterprise Automation: Heavy B2B platforms, marketplaces, and cross-platform integrations. ⚡ 𝐇𝐎𝐖 𝐖𝐄 𝐖𝐎𝐑𝐊 𝐓𝐎𝐆𝐄𝐓𝐇𝐄𝐑 Strategic Discovery: As a CTO, I align your business goals, success metrics, and timeline constraints before writing a single line of code. Architecture Blueprinting: We map out the core database schemas, React frontend components, and Node.js / PHP API flows to ensure long-term scalability. Agile Iteration: Backed by the senior engineering powerhouse at Onix-Systems, we deliver high-velocity sprints with predictable, production-ready releases every 2 weeks. DevOps & Launch: Secure deployment across AWS/GCP/Azure with ongoing tech partnership and proactive optimization based on product metrics. Looking for a Senior Full Stack Developer and a Full-Stack Web Development team to turn your complex concept into a world-class, scalable web platform? 𝐋𝐞𝐭’𝐬 𝐜𝐨𝐧𝐧𝐞𝐜𝐭! Send over your project brief, scope, or existing codebase notes, and I’ll provide a high-level strategic roadmap for your next big launch. ☎️

I build and lead backend systems for SaaS products that need to handle real growth - high load, complex workflows, and revenue at scale. Over the past 5+ years, I’ve done this as a backend engineer and tech lead, designing and leading backend systems for SaaS products built with Node.js & AWS. What I help teams build: - Backend systems for SaaS products that stay stable as users, data, and revenue grow - Complex API integrations and automation-heavy workflows - Product-driven engineering - building systems that directly impact revenue - AWS-based architectures designed to scale predictably without unnecessary cost - AI-powered features used for automation and product workflows Experience highlights: - Led backend development for a SaaS platform generating six-figure monthly recurring revenue (MRR) - Proposed and delivered a feature that directly increased paid conversions and revenue - Built and deployed an AI-powered automation bot for my own business that significantly reduced time spent on customer communication and routine operations How I work: I take full ownership of what I build, communicate clearly, and focus on backend systems that are ready to grow. I care about long-term maintainability and product impact, not just getting features shipped. If you’re building or scaling a product and need someone who understands how backend architecture, cloud infrastructure, and product decisions connect, let’s talk.

Why work with me? 👑 100% Job Success on Upwork ⭐ Top-rated agency 🤝 Using Cursor AI to speed up development 👨‍💻 10+ years of commercial experience 💎 CEO leading 40+ product launches for startups and SMEs Mobile full-stack developer and React Native expert with over 10 years of experience in building and scaling mobile products. While I’ve worked across the entire stack - from backend to frontend to cloud infrastructure - my focus today is on mobile development, particularly using React Native (Expo), Supabase, and Node.js. My core tech stack: 💬 React Native (Expo 🛠️ Node.js / TypeScript / JavaScript ⚙️ React.js / Next.js 💡 Supabase / PostgreSQL / MongoDB