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Full-Stack Developer (5 years) — TypeScript • Node.js • React/Next.js • .NET (C#) I’m a full-stack developer with 5 years of commercial experience building web applications, APIs, and end-to-end product features. My primary stack is JavaScript/TypeScript with Node.js, React, and Next.js, and I also bring strong backend experience with C#, .NET, and ASP.NET Core—so I can work comfortably across the entire system. What I can help with Building and scaling React/Next.js apps (SSR/SSG, routing, auth, dashboards) Designing and implementing REST APIs (Node/Express/Nest or ASP.NET Core) Database work: schema design, migrations, query optimization Integrations: payment providers, third-party APIs, webhooks Performance & reliability: caching, background jobs, error handling, logging Quality: TypeScript-first code, tests, code reviews, clean architecture Fixing and modernizing existing codebases (refactors, upgrades, tech debt) Tech stack TypeScript, JavaScript, Node.js, React, Next.js, Express/NestJS, C#, .NET, ASP.NET Core, PostgreSQL/MySQL, MongoDB, Redis, Docker, Git, CI/CD (GitHub Actions/GitLab CI), Jest/RTL, Playwright/Cypress. How I work I start by clarifying goals and constraints, then deliver in small, reviewable increments with clear status updates. You’ll get maintainable code, predictable progress, and a smooth handoff with documentation. If you share your brief or repo, I’ll reply with a short plan—quick wins, timeline, and the best approach for your next release.

With 10+ years of full-stack development, 100+ scalable web apps shipped, and 10,000+ hours architecting Python backends and modern React frontends, I build production-ready systems that scale with your business. My solutions have delivered: * 65% faster page load times through React optimization & server-side rendering * 50% growth in backend performance via Python API optimization & caching * 90% reduction in deployment issues with automated CI/CD pipelines and containerized environments I'm a Top Rated Senior Full-stack developer, specializing in Python for backend and React / TypeScript for frontend - building seamless, secure, and performant web applications from end to end. Why Clients Choose My Full-Stack Expertise * 10+ years developing end-to-end web platforms for startups and enterprises * 100+ successful production deployments across SaaS, e-commerce, fintech, and internal tools Expert in FastAPI, Django, Flask for backend and React + TypeScript for frontend Strong API design, cloud architecture, and CI/CD automation skills Proven results: faster delivery cycles, reduced infrastructure costs, and improved user experience Backend Engineering (Python) * Architecting and developing RESTful and GraphQL APIs using FastAPI, Django, Flask * Database modeling & optimization with PostgreSQL / MySQL / MongoDB / Redis * Authentication & authorization systems (JWT, OAuth2), background workers, cron jobs * Task queues, caching layers, and performance tuning for scalable services Frontend Development (React / TypeScript) * Building high-performance SPAs with React, Next.js, and modern TypeScript architecture * Implementing server-side rendering (SSR) and code splitting for SEO & speed * Component libraries, state management (Redux / Context), and pixel-perfect UI development * API integration, forms, routing, error boundaries, and testing API Architecture & Integrations * Designing clean, secure, and versioned APIs consumed by multiple frontends * Building microservices and internal tools integrated with 3rd-party APIs (Stripe, Auth0, Slack, etc.) * WebSocket & real-time data flows, background processing, and pub/sub systems Tech Stack & Tooling Languages Python · JavaScript (ES6+) · TypeScript · HTML5 · CSS3 Backend Frameworks FastAPI · Django · Flask Frontend Frameworks React · Next.js Databases PostgreSQL · MySQL · MongoDB · Redis Tooling & DevOps Docker · GitHub Actions · GitLab CI/CD · Nginx · AWS / GCP / Azure · S3 · CloudFront Other REST / GraphQL · WebSockets · Celery / RQ · Background Jobs · Testing (Pytest, Jest, React Testing Library) · ESLint · Prettier Recent Wins * SaaS Platform - Built a Python + React platform from scratch; reduced page load times by 62% with SSR and API caching. * E-Commerce Backend - Migrated a monolith to FastAPI microservices; backend throughput improved by 48%. * Internal Dashboard - Delivered a React admin panel with real-time updates and granular RBAC; boosted team efficiency by 35%. * DevOps Automation - Set up CI/CD pipelines and Docker; 90% fewer deployment issues. * Analytics API - Designed a FastAPI backend serving 1M+ requests/day with Redis caching and async I/O. Use Cases * SaaS Platforms - Multi-tenant apps with secure auth, dashboards, and APIs * E-Commerce Backends - Product catalogs, order flows, and payment integrations * Internal Tools & CRMs - Fast admin panels, role-based access, and real-time updates * API-Driven Systems - High-performance backends powering multiple frontends & mobile apps * Modern Frontends - React SPAs and SSR apps with excellent performance and UX Measurable Results * +65% faster frontend load times with code splitting & SSR * +50% backend performance boost using async APIs & caching * +90% fewer deployment issues with containerized CI/CD pipelines * +40% cost reduction by optimizing cloud infrastructure * 2× developer velocity through clean architecture & automation Ready to scale your product with a battle-tested Full-Stack Engineer? Let's build something fast, clean, and production-ready - together.

Business software solution architect and developer specialising in Microsoft Power Platform (Power Automate, Power Apps, Dataverse) and Microsoft 365 Suite (SharePoint, Microsoft Lists, Outlook, Teams, Excel). I help companies build Microsoft 365 solutions to automate manual tasks, drive efficiency, and improve customer experience. ⚙️ What can I help you with Workflow Automation ↳ Automate repetitive tasks across MS365, Outlook, and other tools Business Apps ↳ Build custom applications that integrate seamlessly with MS365 Business Intelligence ↳ Visualise business data and track KPIs with dashboards and reports System Integrations ↳ Connect MS365 with external systems and third-party services Data Pipelines ↳ Extract data from multiple sources, unify and synchronise across systems ⸻ 🧰 My technology stack and tools ↳ Microsoft 365: SharePoint, Microsoft Lists, Excel, Outlook, OneDrive ↳ Microsoft Power Platform: Power Automate, Power Apps, Power BI, Dataverse, AI Builder ↳ Azure Cloud Platform: Azure Functions, MS SQL Server, Azure Data Factory ↳ Custom Code: TypeScript, JavaScript, .NET, Node.js, React While I value proficiency with specific tools, I strongly believe that the ability to deliver software solutions is largely technology-agnostic. I'm a proponent of choosing the best tool for each job and adapting quickly to new technologies when your project requires it. ⸻ ⏰ Project management Technical skills matter, but from my experience, I learned that successful software delivery depends equally on project management. So here are the steps I take to ensure your project is delivered on time, on budget, and in line with your expectations: ↳ Define a clear problem statement and scope ↳ Establish realistic timelines and budgets ↳ Design a solution that fits the budget ↳ Identify risks and dependencies upfront ↳ Provide regular progress updates throughout ⸻ ⚖️ Why work with me Here are a few things I think you'll find valuable from my diverse experience and the way I work: ↳ Business analysis skills. You don't need polished specs to get started. ↳ Technical proficiency. No problem is too technical for me to solve. ↳ Maintainable solutions. You get solutions that are cost-effective and fast to evolve. ↳ Pragmatic engineering. Custom code as a strategic solution, not the first option. ↳ Reliable delivery. Delivering your project is my job, not a side gig. ⸻ 📩 Get Started Looking for help with business software? Send me a message sharing what you're looking to achieve, and I'll get back to you within 24 hours with my thoughts on the best approach. Looking forward to helping you achieve your goals.

💻 My greatest strengths are my extensive experience and deep expertise in React development and Project Management. I’ve successfully completed numerous projects using React for both web and mobile applications and am committed to continuously enhancing my skills. Here are some key metrics showcasing my professionalism: ⭐ 11,000+ hours worked on Upwork ✅ 70+ successfully executed projects 🔧 Excellent troubleshooting skills 🏆 Exceptional Top Rated Plus engineer 👍 70+ satisfied customers Focusing on React, I deliver high-performance front-end applications and full-stack solutions, leveraging my skills in API integration, automation, and mobile development. Whether creating dynamic web applications or building mobile apps, I provide efficient and scalable solutions. I am proficient in a wide array of technologies, including: 🚀 Key Skills: ⚛️ React, React Native, Redux, JavaScript, Node.js, API Integration 🌐 Full-Stack Development, Web Development, API Integration 🛠️ MongoDB, Express.js, AngularJS, Web3.js, PHP, WordPress 📱 Mobile Development (iOS, Android, Flutter), Firebase, Automation 💻 TypeScript, CSS, HTML, PHP, AI App Development 🤖 Google Chrome Extensions, Hybrid App Development ☁️ Microsoft SQL Server, Microsoft Graph API, Python 📈 SEO, GitHub, ChatGPT API Integration Keywords: Mobile App Development, Android, Android App Development, Dart, Expo.io, Firebase, Firetime Realtime Database, Flutter, FlutterFlow, Hybrid App Development, In-app Purchases, iOS, iOS Development, Java, Kotlin, Native App Development, Push Notifications, React Native, Swift, User Authentication, UX Design. Web Development: React, React.js, Redux, TypeScript, UI/UX Design, AngularJS, API, CSS, Debugging, Express.js, Firebase, GitHub, Google Cloud Platforms, HTML, JavaScript, PHP, PostgreSQL, Web Development, WordPress. Full-Stack Development: API Development, Backend, CSS, Dart, Express.js, Full-stack Development, MongoDB, Node.js, PHP, Push Notifications, Redux, Vuex. AI Development: AI App Development, AI Model Integration, AI Text-to-Speech, ChatGPT API Integration, Machine Learning. I thrive in agile environments, delivering high-quality results and collaborating effectively with cross-functional teams. My deep knowledge of React and full-stack technologies allows me to create solutions tailored to your business needs. If you're looking for a reliable, detail-oriented developer, I'm your go-to expert. 🌟 Check out my portfolio, work history, and client reviews to see my reliability! When you're ready, just send me an invite, and I’ll be happy to help you bring your dream app to life—one that not only generates revenue but is also something you’ll be proud of! 🚀💼

🐇🎩 Building products is like magic: instead of rabbits, I pull working software out of requirement docs.✨ Top Rated Plus on Upwork, top 3% globally ⚡ WHAT YOU GET ▸ 12+ Full Stack Developer React Node | AI development | SaaS Developer | MERN stack ▸ 60+ delivered projects across AI SaaS, CRM systems, dashboards, automation platforms, healthcare, legal tech, real estate, e-commerce, trading software ▸ 15+ AI-powered SaaS MVPs, AI CRM systems, RAG tools, OCR/PDF processing, OpenAI and Claude integrations built from validation to launch ▸ 25+ scalable React, Next.js, Node.js, Python AI backend, PostgreSQL, Stripe, AWS, Docker builds, full technical ownership, secure architecture, production-ready delivery as a Full Stack AI SaaS Developer ⚡ ACHIEVEMENTS | CLIENT WINS FROM AI SAAS & FULL STACK DEVELOPMENT ▸ 26-day ROI recovery recruitment agency launched a Recruiting SaaS Platform with CRM automation, 2x faster candidate workflows ▸ 93% faster estimation construction business reduced quoting time from 8 hours to 30 minutes with a custom Construction Estimator Web App ▸ #4 Product of the Day legal tech founder launched an AI Legal Assistant, RAG-powered document search, OpenAI integration, AI workflow automation ▸ 5+ secure healthcare platforms med spa businesses improved provider/patient workflows with role-based access, admin dashboards, API integration ▸ 10+ CRM & trading systems replaced manual operations with custom CRM platforms, trading dashboards, reporting tools, scalable workflow automation ⚡As a Full stack AI SaaS developer I can support with: ▸ AI-powered SaaS MVPs, product validation ▸ AI agent workflow platforms, workflow automation system ▸ AI-powered Custom CRM system, platform ▸ AI-enabled admin dashboard, panel, machine learning ▸ Role-based workflow platform secure permissions ▸ Secure multi-user web application, scalable backend system ▸ Booking and scheduling platform service businesse ▸ Provider / patient workflow systems healthcare solution ▸ Multi-stage automation workflows complex processe ▸ RAG-powered document intelligence, search system ▸ LLM-powered data processing using openai, modern AI tool ▸ AI-assisted analytics, reporting ▸ OCR and PDF processing pipeline ▸ Rule-based insight engines ▸ Secure backend API development, Third-party API integration ▸ Multi-tenant SaaS platforms workspace isolation ▸ Dashboard, data visualization system ▸ HIPAA / GDPR-compliant platform ⚡ MY CORE STACK as a Full stack Web Developer | Full stack developer React Node | Full stack Developer AI React, Next.js, Node.js, Python, JavaScript, Supabase, PostgreSQL, MySQL, MongoDB, AWS, Docker, nginx, Stripe, AI tools like Openai, Claude, LangChain. I also work with laravel, PHP when a project requires a Full stack developer laravel or integration into an existing system. As a Full stack developer SaaS ( full stack developer ai ) I cover full product delivery: frontend, backend, infrastructure, APIs, and AI logic. I can work as a React developer, Front end developer, Backend developer, Web developer python, React web developer, Full stack web developer depending on the scope. On the frontend, I work with HTML, CSS 3, Tailwind CSS, Vue.js, Angular, Bootstrap for specific stacks or legacy support. For SaaS products, I often work with full stack node.js react development, building React and Node.js SaaS applications with dashboard, admin panel, and secure APIs. I also work as a Full stack developer node | Full stack developer node js, focusing on performance and scalable architecture. When AI is involved, I support projects as a python developer with Python AI backend development, including RAG systems, OCR pipelines, document processing, intelligent automation I also have experience working with mobile app development and can contribute as a React Native developer, building cross-platform apps, react native integrated with backend systems and APIs In addition, I've worked as a full stack developer shopify, wordpress developer workflows, python full stack developer, front end developer react, full stack developer php and niche integrations, including Lazada developer-related marketplaces, helping businesses extend their platforms with custom features, payments and automation. What sets me apart is product thinking. As a technical partner, cto-level contributor, I help define Software Architecture & Design, avoid unnecessary complexity, build solutions that are ready for real users. I also collaborate on web design, ui ux web design, ux designer, ui ux web designer workflows to ensure products are intuitive and easy to use. If you need full stack web development, full stack saas architecture, AI-powered features, reliable Full stack website developer, Full stack developer saas, Full stack AI SaaS developer, I can help you build and scale your product. 💬 Message me with your idea, I’ll share a relevant case, technical approach, clear estimate from a full stack developer.

🏆 7 years as a full stack developer. 50+ React and Node.js products shipped. 1 startup taken to a $25M valuation with $7M raised - Bairro, where I was lead full stack developer and website developer on a React and Node.js platform now used by 50K+ people. That is the track record behind every React and Node.js build I take on. 🚀 30+ SaaS Platform and Web App launches as a Senior Full Stack Developer and Full Stack Engineer. I started as a web developer and website developer before becoming a full stack developer who owns React frontend and Node.js backend equally. My full stack developer react node approach means one Full Stack Web Developer instead of three contractors - 40% faster delivery. 👋 Hi! I am Oleksandr, a Full Stack Developer and website developer with 7 years in React and Node.js. As a react developer I build interfaces in React and react typescript; as a Node.js specialist I run APIs and real-time services. My Full Stack Developer work covers SaaS Web App, Marketplace App, MVP SaaS, and Platform Development. Whether you have a Developer Needed post for a SaaS Product or need a Full Stack SaaS Developer for a Management Platform - I deliver. 📱 20+ industries as a full stack developer. I work as a full stack developer ai specialist and AI Engineer shipping AI Agent features. I deliver full stack developer shopify work, full stack developer laravel builds, python full stack developer projects, and .net full stack developer solutions. As a mobile app developer and React Native specialist I ship Mobile App Development for iOS and Android, including 12+ Real Estate and Property Management platforms. 🌐 100+ website developer projects delivered. My website developer work spans react nextjs and node.js backend developer builds, word press website developer projects, wordpress developer and website design work, shopify website developer stores, hubspot website developer setups, and wix website developer requests. Every website developer project follows SEO best practices with React speed and Node.js power. ⚡ React is in 100% of my full stack developer projects. React powers the SaaS Dashboard, Marketplace App, and Management Platform products I ship. I pair React with Node.js as a full stack node.js react specialist so components talk to APIs cleanly in every full stack developer react workflow. I also use vue, angular, javascript, flutter node.js, and react native for Mobile App Development - but React with Node.js stays my Full Stack Developer core. 🔧 Node.js handles 5M+ monthly requests across my client systems. As a back end developer node.js is my default for REST APIs, GraphQL, and microservices in every Full Stack Developer project. My node.js react pattern carries heavy traffic for SaaS Platform and Web App clients. Node.js runs authentication, payments, real-time messaging, and AI Agent pipelines in every full stack developer engagement. 📲 15+ mobile products as a full stack mobile developer. I build Mobile App Development with React Native, react native mobile, and react native expo. A Full Stack Developer react node architecture spans web and mobile, so one Full Stack Developer owns the whole App Development lifecycle. My react native work covers SaaS Product, Marketplace App, and Real Estate platforms. 🔗 50+ integrations as a Full Stack Developer and web developer. React frontends connect to CMS, e-commerce, and CRM systems. Node.js services plug into Stripe, Twilio, and dozens of APIs. My website developer and Full Stack Developer builds ship SaaS Development results on time. ✅ 0 abandoned projects in 7 years. Every website developer and Full Stack Developer build follows clean architecture: React stays modular, Node.js stays documented, deployments run automatically. React and Node.js are the Full Stack Developer foundation I build on, and I benchmark every Web App and SaaS Platform before handoff. 🔑 Why this full stack developer? A website developer who only knows React ships half a product; a Node.js engineer who never touches the frontend ships the other half. A full stack developer closes that gap. React without Node.js is a demo. Node.js without React is an API nobody sees. A full stack developer ties both together, and a good website developer keeps the result usable. 📌 Hire a full stack developer who writes React like a frontend specialist and Node.js like a backend one - and a website developer who does not disappear at handoff. My React code is documented, my Node.js services are tested, and every full stack developer project I close is a product you can run. That is what 7 years in React and Node.js buys you. 💬 Send me your brief. If it needs React, Node.js, a website developer, or a full stack developer who can own the whole build - let's talk. Every React and Node.js estimate I give is one I stand behind as your full stack developer.