Hire the Best API Developers
in Poland

8 years’ experience | 60+ projects | 𝗠𝗮𝘀𝘁𝗲𝗿’𝘀 𝗶𝗻 𝗗𝗮𝘁𝗮 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 & 𝗔𝗜 | Only 5-star reviews ⭐⭐⭐⭐⭐ Full Stack Developer & AI Developer / SaaS Developer & SaaS Architect — I'm a Python Developer & Web Developer focused on AI Solutions & SaaS, with strong skills as an AI Architect, Python Full Stack Developer / React Developer. You'll get an AI SaaS / Website prototype in 2 days and an AI SaaS solution shipped in 6-12 weeks. 🎯 WHAT I DO I ship production-grade AI SaaS / AI product end-to-end. You come to me when you need: 🔹 Full Stack development delivery — one senior point of contact, one accountable owner 🔹 AI development, AI Integration, LLM integration — RAG pipelines, AI agent, Voice Agent 🔹 SaaS MVP in weeks — built on architecture that scales beyond the prototype 🔹 A technical co-founder mindset — scoping the AI / SaaS development, making architecture decisions, owning the result 🎓 BACKGROUND I’m a Senior Full-Stack Developer / AI Developer & AI Solution Architect with 8+ years as an AI Python developer and 7+ years as a Full Stack Web developer, having delivered 60+ AI, SaaS, Web, Mobile, and Full-Stack projects. I hold a Master’s Degree in Data Science & AI and am preparing a PhD in AI. My focus spans Artificial Intelligence and Software Architecture & Design. 🛠 HOW I WORK As a Senior Full Stack Developer (React Python) and AWS Architect, I lead a small team — Backend Engineer (Python Node.js), Frontend (React Angular Next.js), Full Stack Developer AI (JavaScript Vue.js jQuery Bootstrap), AI Engineer (RAG NLP), 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 & Senior Python AI developer, I act as your delivery manager: one point of contact with 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 developer / SaaS AI Software Architect, I design a SaaS Startup MVP that scales 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 → As an MVP developer, I take SaaS design from 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. As an Open AI developer / AI LLM developer, I also build Machine Learning Python workflows. 🔹 AI/LLM integrations → Claude, ChatGPT-5, LLaMA, Mistral — fine-tuning, prompt design 🔹 RAG & Vector DB → LangChain, FAISS, Qdrant, Pinecone, ChromaDB, pgvector — hybrid search, AI SEO 🔹 Generative AI → Stable Diffusion, SDXL, LoRA — custom image pipelines 🔹 AI ML Engineer → AI automation, deep voice agent, Computer Vision, MCP integrations, dashboards 📌 Full-Stack Development / Web Application Development As an AI 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 Supabase; MERN stack, PHP, Webflow, WordPress developer & website developer. 🔹 Front end developer → React, Next.js, TypeScript, Tailwind CSS, JavaScript, CSS 3, HTML, HTML5 🔹 Backend developer → Python FastAPI, Django, Node.js, Laravel, SQL, MySQL, REST API development, GraphQL API 🔹 Real-time → WebSockets, Server-Sent Events for streaming AI 🔹 Web Application architecture & Web Development → modular monorepos, microservices 🤖 SENIOR AI-AUGMENTED DEVELOPMENT As an AI Engineer / Python Backend Developer / AI backend developer, I use modern AI tools to speed delivery: Git, GitHub Copilot for coding, ChatGPT for reasoning, Cursor for refactoring, Claude Code with MCP for architecture in full stack developer SaaS projects, Replit for prototyping, Lovable for MVPs, Bolt.new for web experiments, v0 by Vercel for UI generation. 🏆 MY UPWORK TRACK RECORD ✅ Top Rated Plus Expert ✅ 100% Job Success Score ✅ $200K+ earned delivering Full-Stack / SaaS & AI Solutions ✅ 17 successfully completed Upwork jobs ✅ Only 5-star reviews ✅ Upwork Skill Certified — Python Developer; Back-End Development 💬 "Thanks to Ilya for developing my AI-powered SaaS. Ilya proved himself as an excellent AI software developer & full stack developer, proposed a clean ui ux SaaS web design, built a solid backend with Python FastAPI, a front end with React" — Dmitri Dalla-Riva, Aidtrade, Australia 🤝 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!

⚒ Technology stack C#, .NET, WPF, Revit API, AutoCAD API, Civil 3D API, Navisworks API, Inventor API, BIM 360 API, Autodesk Platform Services (formerly Autodesk Forge), HTML, CSS, TypeScript, Angular, React, IFC.js, WebGL, Three.js, AWS, Microsoft Azure, GitHub Actions, Figma, Forma, Machine learning for construction 🔹 Custom Autodesk Revit Plugins, Add-ins 🔹 Machine learning, AI for construction 🔹 BIM and CAD, Design Workflow Automation 🔹 3D Product Configurators, Revit Family Generators 🔹 Design Automation with Autodesk Platform Services (formerly Autodesk Forge) 🔹 Material Take-off, Bill of Materials (BOM) Addins 🔹 Web-based IFC Applications 🔹 Serverless Cloud Applications 🔹 Shop Drawings Automation 🔹 Point Cloud Processing 🔹 Autodesk Forma 🔹 Data Conversion: BIM to JSON, RVT to JSON, etc. I am desperate to provide perfect service for software development. Certified Professional user of Revit. Let's elevate your project together!

Welcome to my profile! With over 9 years of experience as a PHP, React, Python developer, I am passionate about creating efficient, scalable, and secure web applications. Throughout my career, I have worked with a range of frameworks and CMS platforms, including Laravel, Symfony, Spryker, and WordPress, React, Next, Python, Go. My expertise lies in developing custom web applications, implementing complex functionalities, and optimizing performance. I have a deep understanding of Laravel and Symfony, two widely-used PHP frameworks known for their robustness and flexibility. I have leveraged these frameworks to build tailored solutions for clients across various industries. In addition to Laravel and Symfony, I have extensive experience with Spryker, a powerful e-commerce framework. I have successfully developed and customized e-commerce solutions using Spryker, delivering seamless online shopping experiences for businesses and their customers. Furthermore, I have worked with WordPress, a popular content management system, to create engaging websites and blogs. I am proficient in developing custom themes, and plugins, and optimizing WordPress websites for improved performance and user experience. My skill set includes: - PHP (Spryker, Laravel, Symfony, Wordpress) - Doctrine, Propel, Eloquent - MySQL, PostgreSQL - Redis, Memcached ElasticSearch - RabbitMQ, Google queues - Github, Gitlab, Bitbucket - AWS / Unix / Console - Restful API -React, Next.jsm Python, Go Throughout my career, I have successfully delivered projects for clients in various industries, meeting their unique requirements and exceeding their expectations. I take pride in my ability to translate complex concepts into user-friendly solutions and my commitment to delivering high-quality work. If you are looking for a skilled developer with expertise in Laravel, Symfony, Spryker, React, Python, Go and WordPress, I am confident in my ability to contribute to the success of your project. Let's discuss how I can bring your ideas to life and achieve your desired outcomes.

Upwork changes its algorithm every few months.... Clean architecture has survived for decades. We bet on the second one. ⚡ 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. ☎️

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.

🥇 TOP RATED PLUS 🙌 100% JOB SUCCESS 🧐 15+ years of varied experience in architecture and development of JavaScript/Node.js/PHP web applications, scrappers and services for different companies and startups. I love to skillfully combine various technologies to solve non-standard problems of any architectural and logical complexity. I masterfully use cluster technologies, which allows me to create high-quality, high-speed, high-availability, fault-tolerant products that don't require constant maintenance. I can easily bypass any protection to obtain data from any sources. I'm interested in long-term relationships. ✓ Technologies:  Web Architecture | Distributed Systems | High Availability Clustering  Web Scraping | Content Distribution Networks (CDN)  Microservices | Virtual Machines (VM) | Live Video Streaming  Virtual Private Networks (VPN) | Containerization ✓ Programming languages & platforms:  JavaScript/TypeScript | Node.js | PHP ✓ Databases:  PostgreSQL | MySQL | MariaDB | Patroni  Redis | Redis Sentinel | Redis Cluster | MongoDB  Knex ORM | Prizma ORM | Drizzle ORM | Eloquent ORM | Mongoose  SQL | NoSQL ✓ Back-end technologies:  Node.js | Express.js  Laravel | Eloquent | Sanctum  Fetch | Ofetch | Axios  WebSockets | Socket.io | WebRTC  Ajax | JSON REST API | GraphQL | OAuth | JWT  Blockchain | Solidity | Web3.js  Stripe | Google Maps API  Data Mapping & Combination  Load Balancing  Telegram Bot Development ✓ Front-end technologies:  Vue 2 | Vue 3 | Pinia | VueX | Nuxt 2 | Nuxt 3 | Composition API | Options API  PrimeVue | Quasar | Vuetify | Tailwind CSS  Fetch | Ofetch | Axios  WebSockets | Socket.io | WebRTC  Server Side Rendering (SSR)  D3.js  Chrome Extensions  HTML | CSS | SASS/SCSS | LESS | PostCSS ✓ Automation/Crawling/Scrapping/Scanners:  Puppeteer  Chrome Extensions | Manifest V2 | Manifest V3  Perimeter X bypass  CloudFlare bypass  JS Injections  Decryption | Decoding  HTTP Proxy/VPN using ✓ Bookmaker Odds, Widgets & Livestreams (zero latency scanners):  Bet365 | Pinnacle | BetMGM | Betradar | Virginbet | Fonbet | Olimp ✓ Desktop technologies:  Electron.js ✓ Tools & Common:  Docker | Docker Compose | Kubernetes | Grafana | OpenSearch | Ansible  Git | GitHub | BitBucket | GitLab  CI/CD  NPM  Apache | Nginx  Gzip | Brotli  Java | C# | C++  Linux Administration (CentOS/Debian/Ubuntu) ✓ Cloud Providers:  Amazon Web Service (Lambda, EC2, S3, API gateway, Cognito, DynamoDB, etc.)  Microsoft Azure  Google Cloud Platform  Firebase (Cloud FireStore, Realtime Database, Cloud Functions)  Digital Ocean  Hetzner Cloud ✓ Areas of interest:  iGaming | Betting | Sportbooks | Onling Gambling | eSports  Artificial Intelligence | Deep Learning | Machine Learning  Cryptocurrency Trading If you have any questions or want to discuss your project, feel free to contact me. I'm always happy to make time for you. Thanks.