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👋 Need a high-load Java platform that scales without a glitch? 🚀 I provide full-stack ownership with Spring Boot and React Native, turning complex ideas into secure, production-ready reality. Backed by 20+ years and 100+ delivered projects, I build code that works for your bottom line, not just your repo. Check out my page to see my portfolio! 🛡️ As a Java Developer I've built high-load backend systems, REST AP payment solutions document processing platforms, and business applications used by thousands of users. As a Full Stack Developer and React Native Developer I've helped startups and growing companies launch scalable products while maintaining security, performance, and compliance. Throughout my career, I've worked with startups, established businesses, and enterprise clients, helping them transform ideas into reliable software products. My experience covers the entire development lifecycle, from architecture planning and technical discovery to development, deployment, optimization, and long-term support. My expertise includes Java Developer Spring Boot React Native AWS PostgreSQL Docker Kubernetes microservices cloud infrastructure and secure software architecture 💪 Full Stack Java Developer Expertise ✔️ 20+ years of Java development 100 successful projects using Java, Spring Boot, Spring Security, Hibernate, and enterprise architectures ✔️ Full Stack Development covering backend architecture database design frontend implementation and React Native mobile applications ✔️ Spring Boot Development, REST API microservices cloud-native applications and high-performance backend systems ✔️ Backend Architecture, distributed systems, 50 third-party integrations, authentication systems, and secure API development ✔️ PostgreSQL MySQL Redis AWS Docker Kubernetes CI/CD performance optimization and legacy system modernization ✔️ Extensive experience designing business-critical applications where scalability, maintainability, security, and long-term growth are key requirements ✔️ Experience integrating payment gateways, healthcare systems, cloud services, identity providers, and external enterprise platforms ✔️ Strong understanding of software architecture, design patterns, clean code principles, and modern development practices ✔️ Experience leading technical initiatives, collaborating with distributed teams, participating in code reviews, and helping businesses make technology decisions 🏥 Healthcare Software Development Expertise As a Senior Java Developer and Full Stack Developer, I've built secure and HIPAA-compliant healthcare software for startups, clinics, and digital health companies. ✔️ 100+ healthcare applications including EHR/EMR systems, telemedicine platforms, patient portals, and engagement solutions ✔️ 80+ FHIR & HL7 integrations for healthcare interoperability and secure data exchange ✔️ 150 React Native healthcare apps with Apple HealthKit, Google Fit, BLE, and real-time health monitoring ✔️ 100+ healthcare features delivered, improving patient engagement and clinical workflows ✔️ 50+ HIPAA-compliant architectures with encrypted storage, audit logging, RBAC, and secure APIs ✔️ 100 Java Spring Boot backend systems with up to 99.9% uptime ✔️150+ healthcare workflow automations, provider portals, appointment management, and patient communication platforms 💳 Fintech Software Development Expertise As a Full Stack Java Developer I've built PCI DSS-compliant fintech platforms focused on payments, identity verification, and transaction security. ✔️ 50+ Stripe, Apple Pay, Google Pay, and 3D Secure (3DS) integrations ✔️ 20+ KYC & AML workflows for onboarding and compliance automation ✔️ 100+ payment features delivered, reducing friction and improving transaction success ✔️ 25+ payment platforms, transaction systems, and financial API integrations ✔️ 15+ PCI DSS architectures with encryption, tokenization, audit logging, and secure authentication ✔️ 50+ financial reporting, payment workflows, transaction monitoring, and compliance solution 🏆 Key Results | Java Developer Spring Boot | Full Stack Java Developer | React Native ✔️ 20+ years of commercial experience as a Full Stack Java Developer ✔️ 100+ enterprise projects across Healthcare, FinTech, SaaS, and AI ✔️ 55+ AI-powered products using OpenAI, Claude API, FastAPI, AI Agents & RAG ( use Lovable \ Bollt.new \ Base44 and etc ) ✔️ Up to 100% uptime for mission-critical healthcare and fintech systems ✔️ Up to 40% higher patient engagement through digital health solutions ✔️ Up to 25% lower payment decline rates with optimized payment workflows ✔️ Up to 35% faster application performance and scalability improvements ✔️ Up to 90% fewer security vulnerabilities with secure architectures 📩 Looking for a technical partner who understands both technology and business goals? I help companies build, scale, and modernize Healthcare Fintech SaaS and Enterprise products using Java Spring Boot Full Stack technologies and React Native

Hi there! For the last 7 years I have been professionally helping clients turn their ideas into a product. With proven ability of understanding customers' needs and outside the box thinking I am always eager to do the things right. If you want energetic, positive thinking problem solver with always fresh ideas in mind, I'm your man. Among areas of my expertise you might be interested in: - Qt - C++ - Rust - Golang - Blockchain - Cryptocurrency - Mobile, Desktop and Crossplatform Development.

Want smarter automation, better user engagement, and AI-powered growth? Send me your idea and I’ll break it down into a clear AI Chatbot Development strategy with quick wins and scalable long-term architecture. As your AI Chatbot Developer I map the fastest path to launch, and show how AI Chatbot Development drives business development and revenue 🤖 🔹 Senior AI Agent Developer with 18+ years of programming experience (since 2006) 🔹 Fast MVP AI Chatbot Development with 100+ agents delivered for the last 5 years 🔹 AI Agent Developer shipping 2x faster, resolving 70%+ of customer queries autonomously 🔹 Business-first mindset focused on ROI 🔹 Trusted AI Agent Development automating 30+ daily tasks and saving 400+ hours/month on average 🔹 Top Rated AI Chatbot Developer with 50+ projects delivered and 5-star reviews on Upwork alone 🔹 Fast, clear communication & startup-friendly mindset I’m a senior AI Agent Developer specializing in AI chatbot, AI platforms and automation-driven businesses. As an agentic ai developer, my work focuses on building production-ready AI Chatbot systems, AI Agent workflows, AI RAG, AI assistants, autonomous agents, Telegram trading bots, and crypto Telegram bots that scale securely and reliably. Whether you need website chats, voice AI agent, customer support automation, Telegram bots, Slack bots or advanced AI RAG systems, my approach as an AI Chatbot Developer ensures real business impact—not just demos. 🚀 AI Results I’ve Delivered • AI Chatbot Development of 100+ Python chatbots deployed across websites, Telegram, and Slack shipped across 30+ countries • 50+ AI Agent Development and bot development projects automating customer support and lead generation • 30+ AI workflow automation pipelines cutting manual processing time by 70%+ • Data Science and Data Analysis pipelines reducing human support workload by 60%+ • 30+ RAG, Neural Network and Natural Language Processing (NLP) solutions improving response accuracy by 40%+ • Generative AI, Artificial Intelligence integrations raising user engagement by 45%+ • Machine Learning and Deep Learning architectures in PyTorch and TensorFlow lifting AI prediction accuracy to 95%+ • AI sales agent and deal closer chatbots lifting conversion rates by 35%+ • As a Web Developer, 60+ React, JavaScript and Node.js dashboards and web apps shipped around chatbot deployments • 18+ years of PHP and WordPress development powering 40+ chatbot integrations since 2006 • 25+ Blockchain and Web3 chatbots wired into smart contracts and crypto payments 📌 Full-Spectrum AI Chatbot Development Services • AI Agent Development, bot development and AI workflow automation • Chatbot SaaS assistant • AI Agent Developer for startups and enterprises • AI RAG chatbot system for private data & SaaS • AI customer support & lead generation • Multi-agent systems and AI Agent Developer services • AI Agent automation & conversational workflow • Website chatbot, Slack bot & Voiceflow chatbot • Business automation and AI integration • WordPress, API integration & admin dashboard • Blockchain & Web3 chatbot • AI Agent crypto and Blockchain Telegram trading bots • Practical deployments for customer support (Tidio) and lead generation (Conversiobot) Developer Stack • LangChain, LangGraph, CrewAI, AutoGen, OpenAI • Open AI chatbot, Claude, Gemini, GPT-3 & GPT-4 integrations • Flask, FastAPI, DialogFlow, ManyChat, Botpress, Rasa chatbot & GHL chatbot • FAISS, Chroma, Pinecone, Weaviate, MySQL, PostgreSQL, MongoDB • Website chat, Telegram bot, WhatsApp chatbot, Facebook chatbot, Instagram chatbot, Slack & Discord bot • Python, PHP, JavaScript, Node.js, React, PyTorch & TensorFlow 📈 Advanced AI Chatbot Development & AI Agent Development I don’t just “build bots” — I engineer intelligent systems. My AI Chatbot Developer process covers conversation design, model selection, AI Agent Development, and scalable backend architecture. Using LangChain, LangGraph, ai agent n8n, FastAPI, and modern AI pipelines, I've built 100+ AI Agents that reason, retrieve data, and execute workflows — as your expert AI Agent builder trusted by 50+ businesses and AI Agent creator with 70%+ autonomous query resolution. As a senior AI Chatbot Developer, my focus is reliability, security, and measurable results for chatbot marketing and business automation. • For SaaS & AI platforms, as your AI Agent Developer I build AI RAG chatbot solutions that answer accurately from private data. • For startups, as your AI Chatbot Developer I provide MVP-focused AI Chatbot Development that scales smoothly. 📩 Looking for a senior AI Chatbot Developer specializing in AI Chatbot Development, or an AI Agent Developer for AI RAG systems and conversion-focused chatbot solutions? Let’s talk. I build intelligent systems that actually work — and scale.

Senior Front-End Developer | Expert in Angular & React Native & Vue | TypeScript | SCSS | Node.js 🔹 8 Years of Professional Experience 🥇Top Rated (100% Job Success Rate) I’m an experienced Front-End Developer with a strong foundation in modern web technologies and over 7 years of experience in building scalable, high-performance web applications. My focus is on delivering visually appealing and user-friendly solutions that exceed client expectations. 📌 𝐌𝐲 𝐄𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞: ✔️ 7+ years of professional experience in web and mobile app development. ✔️ 5+ years of uninterrupted experience with Angular 2+ and related technologies (TypeScript, RxJS, NgRx and different UI libraries). ✔️ 2+ years of development experience with React/Redux/React Native, Nuxt.js, Vue.js and Wordpress ✔️ good knowlege of AJAX, JSON, REST API, GRAPH QL, OOP, SOLID, DRY, KISS, YAGNI ✔️ good understanding Docker, CI-CD integration ✔️ good knowlege Node.js, Express, Mongo DB, PostgreSQL 📌 𝐇𝐨𝐰 𝐈 𝐂𝐚𝐧 𝐇𝐞𝐥𝐩 𝐘𝐨𝐮: ✅ Implementing sleek, pixel-perfect interfaces based on detailed UX/UI designs ✅ Collaborating with designers and developers to bring your vision to life ✅ Ensuring scalable, optimized, and maintainable code for long-term success ✅ Creating reusable components and optimizing applications for maximum performance Strong communication skills, work well both independently and within the team. Quickly learns and masters new concepts and skills. 📌 𝐌𝐲 𝐒𝐤𝐢𝐥𝐥𝐬: Angular, AngularJS, Angular CLI, Single Page Applications (SPA), Reactive Forms, Template-Driven Forms, RxJS, NgRx, State Management, Component-Based Architecture, Dependency Injection, TypeScript, JavaScript, Progressive Web Applications (PWA), Lazy Loading, HTML5, CSS3, SCSS, SASS, Bootstrap, Material Design, Angular Material, TailwindCSS, React Native, Vue.js, Vuetify, Pinia, PrimeNG, Kendo UI, Webpack, Babel, ESLint, RESTful APIs, GraphQL, API Integration, CRUD Operations, RxJS Operators, Jasmine, Karma, Protractor, Responsive Design, Cross-Browser Compatibility, Accessibility (WCAG), Figma, Git, GitHub, GitLab, Bitbucket, CI/CD, Docker, Firebase, Websockets, Socket.IO, Data Visualization, Chart.js, Highcharts, Agile Development, Scrum, Jira, Trello, Slack, Website Optimization, Performance Tuning, Lighthouse Audits, Browser Developer Tools, SEO Best Practices, Localization, Internationalization (i18n), Security Practices (OWASP), Design Systems, Component Libraries, Frontend Architecture, Code Refactoring, Debugging, Documentation, UI/UX Collaboration, SaaS Platforms, Ecommerce Platforms, Real-Time Applications.

Is your blockchain product ready for real users, or is it a prototype that breaks under live transactions? Most Web3 projects fail at the boundaries between smart contracts, wallets, trading operations, and backend systems. 🏆 20+ years architecting production systems at principal engineer level 📊 $200K+ earned on Upwork across 32 architecture projects 🎯 100% Job Success Score, Top Rated Plus on Upwork ⚡ 11 years architecting Fintech / Trading / Accounting solutions ⚡ 8 years architecting blockchain products across Bitcoin, EVM, Solana ecosystems 💼 CEO at Osambit, a 20-person engineering team ✅ Enterprise Blockchain Architect certified, former Sr Principal Engineer at Nordstrom ⭐⭐⭐⭐⭐ "We've had the opportunity to collaborate with the Osambit team, and it's been a great experience. They're highly professional, responsive, and truly understand the final goal. Their technical expertise and ability to deliver on time have been key to the success." (Alwyn V., IXO World) As a Blockchain Architect with 20+ years of production engineering experience and two years focused on Web3, I design blockchain and fintech products that operate reliably beyond a demo. I work across Solana and EVM networks—including Ethereum, Polygon, Base, BSC, and Arbitrum—as well as enterprise platforms such as Hyperledger Fabric and Besu. My work connects secure smart-contract, wallet, payment, and remittance flows with the backend systems, operational controls, and user experiences a real product needs. Every engagement starts with architecture: chain selection, custody and transaction boundaries, compliance-aware workflows, failure modes, scalability, and security. That architecture-first approach helps blockchain and neobanking products withstand live usage, not just testnet scenarios. 🔶 Centralized exchange: architecture for trading operations, wallet flows, and reliable backend integration 🔶 Custodial wallets: secure custody, transaction handling, and multi-wallet platform architecture 🔶 Trading automation system: real-time blockchain-integrated trading workflows with operational safeguards 🔶 Liquidity automation system: DeFi and liquidity-management automation across Solana and EVM ecosystems 🔶 Fintech, neobanking & remittance apps: payment, account, wallet, and cross-border transfer architecture 🔶 Bitcoin mining facility control panel: operational dashboard and control-system architecture for mining infrastructure 🔶 Blockchain-integrated game: NFT features, token and wallet integrations, and production-ready game backend design 🔶 Enterprise blockchain solutions: permissioned-network architecture and public-chain integrations using Hyperledger Fabric or Besu 🔶 Nordstrom (Sr Principal Engineer, 5 years): architected 9+ enterprise systems | led 10 offshore engineering teams | supply chain, payment, logistics domains WHAT I DO ✅ Blockchain Architecture: chain selection, system design, security boundaries, and production rollout planning ✅ Solana Development: Rust programs, SPL standards, RPC integrations, and high-throughput DeFi systems ✅ EVM & Smart Contracts: Solidity development and integrations for Ethereum, Polygon, Base, BSC, and Arbitrum ✅ Wallet & Custody Systems: custodial wallet architecture, secure transaction handling, and multi-wallet integrations ✅ Fintech, Neobanking & Remittance: payment flows, account and wallet systems, cross-border transfers, and operational controls ✅ DeFi, Trading & Liquidity Automation: trading workflows, liquidity systems, DEX integrations, and operational controls ✅ NFT & Tokenized Products: NFT minting, metadata, marketplace and royalty logic, and blockchain-integrated game features ✅ Enterprise Blockchain: Hyperledger Fabric and Besu solutions, permissioned-network architecture, and API or oracle integrations ✅ Full-Stack Web3 Platforms: React interfaces, Node.js or Python backends, web3 integrations, and real-time transaction services ✅ Production Infrastructure: AWS, Docker, Kubernetes, CI/CD, observability, automated testing, and scalable data systems WHO I WORK WITH 🎯 B2B and B2C companies building blockchain products, fintech and neobanking apps, exchanges, wallets, DeFi platforms, or games 🎯 Founders and CTOs who need Web3, payment, or remittance systems running in production with real users and real assets 🎯 Teams with multi-week engagements (4+ weeks minimum), not 5-minute tasks 🎯 Companies that understand blockchain architecture is a system design and security problem, not just a smart-contract problem 🎯 Clients who value senior engineering judgment over the cheapest hourly rate MY PROCESS 1️⃣ Architecture Review: 24-hour turnaround on an initial system map, risk review, and scope estimate for your blockchain or fintech product. Close collaboration with business and deep domain immersion. 2️⃣ Design: chain selection, smart-contract, wallet, payment, and remittance boundaries, backend integration, and security plan 3️⃣ Build: production blockchain or fintech

Hi there! 👋 I’m a Fullstack Software Engineer from Lviv, Ukraine, with 6+ years of experience in Frontend, Backend, and Mobile Development. I specialize in building high-performance, scalable, and user-friendly applications that drive real business results. 🔹 What I Do Web Development React, Next.js (14/15), TypeScript, Redux Toolkit, Zustand Node.js, Nest.js, Express.js, PostgreSQL, MongoDB, Redis, BullMQ Performance optimization (20–40%), CI/CD, AWS, Azure Mobile Development React Native + Expo (iOS & Android) Biometric authentication, push notifications, media attachments Smooth UX, localization (i18next), charts/data visualization Blockchain & Web3 Wallet integrations: web3.js, Ethers.js, Wagmi, Web3Modal NFT platforms, marketplace aggregation, OpenSea.js UI/UX & Integrations Tailwind, shadcn, Material UI, Radix, AntD Image optimization & automation (Sharp, Canvas API) Accessibility & internationalization (i18n) Cloud & DevOps AWS, Azure (App Service, CosmosDB, App Insights) Docker, CI/CD pipelines, Firebase 🔹 Selected Projects Cross-platform caregiving app with biometric authentication and cloud integration (React Native, Expo, Azure). NFT aggregator platform with blockchain and wallet support (Next.js, Web3). Luxury fashion marketplace with scalable backend, caching, and job queues (Next.js 14, Nest.js, Redis, BullMQ). Fullstack application with hundreds of active users (Next.js 15, Nest.js). Large-scale ECM platform for enterprise clients (ASP Classic, React, C++, C#). 🔹 Why Clients Work With Me I focus on business outcomes — boosting revenue, conversions, and performance. Experienced in startups, SaaS, and enterprise projects. Deep technical expertise, from low-level Rust & C++ to modern React Native & Web3. Strong communication and Agile/Scrum experience ensure smooth collaboration. 💡 Need a Fullstack or Mobile Engineer to bring your product to life, scale it effectively, and ensure long-term stability? Let’s build it together! 🔑 Keywords: Fullstack Developer, React Developer, React Native, Next.js Developer, Node.js, Nest.js, TypeScript, JavaScript, Redux Toolkit, Zustand, Tailwind CSS, shadcn, Mobile App Development, iOS, Android, Expo, Blockchain Developer, Web3, NFT, Ethereum, Smart Contracts, PostgreSQL, MongoDB, Firebase, AWS, Azure, Docker, CI/CD, API Integration, GraphQL, REST API, UI/UX, Cloud Services, Agile Development, Scrum, Performance Optimization