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I am an ACM-ICPC World Finalist and software engineer. I have been developing backend and DevOps solutions using C++, Java, and Python since 2016. I have experience in multiple domains that include fintech, agrotech, health tech, IoT, and Saas. I have been working as a remote developer with globally distributed teams since 2019. I am a quick learner, good with communication, proactive and punctual human being. Nothing excites more me than a challenge that is necessary but difficult to solve. I am also a competitive programmer and expert in data structures and algorithms. I have a decent understanding of UNIX systems especially how different types of data structures are blended to solve complex problems of operating systems. I am a team player and can work as solo as well. I never compromise the quality of my work doesn't matter how the pressure is. And, I believe in requirement analysis as the most crucial part of engagement.

STRIPE CONNECT | STRIPE BILLING | STRIPE RADAR | STRIPE API | STRIPE CHECKOUT | STRIPE TERMINAL | FINTECH | SAAS | AI | PAYMENTS | COMPLIANCE (PCI DSS, GDPR) If Stripe is slowing down your product, breaking your billing logic, or causing failed payments you can’t explain, I can fix that. I’ve delivered 100+ Stripe integrations for SaaS and tech companies, and I’m a 4× Stripe Certified professional. You’re not getting a basic integration, you’re getting a payments system designed to reduce churn, recover revenue, and scale with your growth. I specialize in building Stripe systems that directly impact metrics like churn, AOV (Average Order Value), LTV, and checkout conversion rates. I don’t just plug APIs. I step into your architecture and make sure your billing, subscriptions, and payment flows are optimized end-to-end. I can help if you’re dealing with: 🔹 High checkout abandonment rates 🔹 Unexpected churn from failed payments or poor retry logic 🔹 Broken or confusing subscription upgrades/downgrades 🔹 Low AOV due to poor pricing or payment flow design 🔹 Inconsistent or unreliable webhook handling 🔹 Stripe setups that “work” but don’t scale What I can help you with: 🔹 End-to-end Stripe integration for SaaS platforms 🔹 Subscription architecture (plans, trials, proration, lifecycle logic) 🔹 Reducing churn with smarter retry logic and dunning strategies 🔹 Checkout optimization to improve conversion rates 🔹 Webhook architecture (reliable, scalable, no missed events) 🔹 Stripe account audits with revenue-focused insights 🔹 Advanced Stripe products (Connect, Sigma, custom workflows) If you already have developers, I can work directly with them or guide them through the correct architecture in live sessions. Most Stripe implementations leave money on the table. I help you close those gaps so your payments system actually drives revenue, not just processes it. If you want to improve conversion, reduce churn, or fix hidden issues in your Stripe setup, send me a message and let’s take a look.

I build production-ready AI systems for businesses that want to automate workflows, integrate LLMs, and launch reliable AI features — not just demos. My core work includes RAG applications, AI agents, chatbots, workflow automation, FastAPI backends, Dockerized deployments, and cloud-based AI integrations using OpenAI, LangChain, Python, and vector databases. Most AI developers can connect an API. Very few can ship a system where the AI behaves reliably under real-world constraints. That's the gap I fill. 🎯 I help businesses integrate AI into their workflows and deliver practical solutions that solve real problems. 🚀 What I've Actually Shipped: ✅ A full agentic pipeline that extracted structured clinical trial data from unstructured medical PDFs and published HL7 FHIR resources via REST API — reducing manual extraction time by ~70% ✅ A Clinical Decision Support System for heart failure — processed unstructured doctor notes, extracted 10+ clinical parameters via NLP, and generated GPT-4-powered treatment recommendations with safety constraints ✅ A FastAPI-based quantitative research platform — modular backend handling market data ingestion, backtesting, optimization, and AI-assisted report generation for an international client ✅ A Cloud-Native LLM Inference System — OpenAI-compatible endpoint using vLLM and Modal GPU infrastructure, sub-200ms latency 🧠 Where I'm Genuinely Different: Healthcare AI is my sharpest edge. HL7 FHIR, AWS Comprehend Medical, clinical NLP — this stack is rare. If you're building anything touching medical data, patient workflows, or clinical AI, you won't find many engineers at any level who've shipped in this exact space. I also treat AI output with engineering discipline. I know when a model is hallucinating a field name. I know when structured output needs schema-controlled prompting to be safe. I build fallbacks, not faith. 🔒 ⚙️ Tech I Work With Daily: Python · FastAPI · Flask · Streamlit · OpenAI API · Google Gemini · AWS Comprehend Medical · HL7 FHIR · NLP · REST APIs · Docker · PostgreSQL · GitHub · Prompt Engineering · LLM Workflows 🤝 I Work Best With Clients Who: → Have a real problem, not just a vague AI curiosity → Want production-ready systems, not toy prototypes → Value clear communication and zero-surprise delivery 📩 Send me a message describing what you're building. If it's a fit, I'll tell you exactly how I'd approach it — before you commit to anything.

🟢 Looking for a developer who can boost your business processes using AI? 🟢 Hi, I’m Vitaliy, Top Rated Plus Python Developer and Automation Expert at DataOx with 10+ years of experience in Python and Java backend development, AI-powered automation platforms, LLM integrations, and large-scale data systems. For 8 years on Upwork I’ve completed numerous projects, maintaining a 97% Job Success score, delivering production-ready systems, AI agents, workflow automation solutions, data pipelines, and intelligent backend architectures that help companies reduce manual work, process high volumes of data, and scale operations efficiently. ⭐️⭐️⭐️⭐️⭐️ "The team is extremely efficient, creative, communicative, and flexible. They are excellent at bringing ideas and concepts to life. Our team has worked with other developers in the past, and no one compares to these guys. Do yourself a favor and hire them for your project." What I can help you with: • Web scraping & data extraction (complex, dynamic websites, anti-bot bypass) • API development & integrations (REST APIs, third-party services) • Workflow automation, RPA & backend systems • AI solutions: AI Chatbots, AI Agents & AI Automation for business workflows, LLMs, NLP, bots, intelligent processing • ETL pipelines & data engineering • System integration & custom tools • Python and Java backend, Web Applications & SaaS platforms My Technical Stack AI & LLM Systems: OpenAI API, LangChain, PyTorch, TensorFlow, LLM integration, RAG pipelines, multi-agent workflows, prompt engineering & optimization, AI chatbot backends Backend & Automation: Python, Java, FastAPI, Flask, Django, Spring Boot, REST APIs, Playwright, Selenium, Scrapy, BeautifulSoup Frontend: JavaScript, TypeScript, ReactJS, Next.js, Tailwind CSS Data & Infrastructure: Pandas, SQLAlchemy, PostgreSQL, MongoDB, BigQuery, Airflow, Docker, Kubernetes, AWS, GCP, Azure My Results in Numbers: 🔶 AI Recruitment Platform: Built AI hiring platform with 900K+ candidates, 20K jobs, 2.5K companies, 120K assessments/year, 20K video interviews, 680K candidates via integrations. 🔶 Global Certification Data Platform: Automated aggregation of 500K+ records/month, reducing search time from days to 15–30 minutes and accelerating deal cycles by 3-5x. 🔶 AI Document Intelligence System: Processed 1M+ documents/year with LLM, achieving 90%+ extraction accuracy, reducing manual work by 80%, handling 50+ document types, and scaling to 10K+ documents/day with automated validation Why Clients Choose Me Experience: 10+ years in backend engineering, Python development, Java Development and scalable AI systems Proven Quality: 97% Job Success Score and Top Rated Plus on Upwork Expertise: AI automation, LLM integrations, workflow automation, and production-ready backend architectures 📩 Send me your project requirements, and I’ll provide a clear, high-impact strategy to turn your vision into reality.

I help startups, agencies, and businesses build secure, scalable, and high-performance web applications using modern technologies and AI-assisted development workflows. With strong experience in backend engineering, API development, cloud infrastructure, and frontend frameworks, I deliver clean, maintainable solutions that are fast, reliable, and production-ready. What I Can Help You With ✅ Custom Web Application Development ✅ REST API & GraphQL Development ✅ SaaS Platforms & Business Systems ✅ AI-Assisted Development & Automation ✅ Third-Party API Integrations ✅ Performance Optimization & Security Hardening ✅ Legacy System Upgrade & Modernization ✅ Cloud Deployment & DevOps Setup Backend & Web Technologies • Laravel, Django, Spring Boot, Yii2 • Express.js, NestJS • WordPress, Drupal, Magento • PHP, Python, Java, JavaScript, TypeScript • MySQL, PostgreSQL, MongoDB, Redis Frontend Development • React.js, Vue.js • Tailwind CSS, Bootstrap • Alpine.js, Livewire, HTMX Cloud & DevOps • AWS, GCP • Docker, Kubernetes • CI/CD Pipelines • Linux, Nginx, Apache API & Integrations • Stripe, PayPal • Twilio, Firebase • Slack, Zapier, Xero • REST APIs & GraphQL AI Development Workflow I actively use modern AI development tools to improve delivery speed, code quality, debugging, and architecture planning: • Cursor • Claude • ChatGPT • GitHub Copilot Why Clients Work With Me ✔ Clean, maintainable, scalable code ✔ Fast communication & reliable delivery ✔ Strong debugging and problem-solving skills ✔ Production-ready deployment experience ✔ Security-focused development approach ✔ Ability to work independently and take ownership Whether you need a custom platform, backend API, cloud deployment, or ongoing development support, I can help turn your ideas into reliable software solutions. Let’s build something great together.

Expert-Vetted AI & Full-Stack Engineer | 100% Job Success | 30+ Projects | $170K+ Earned Past Experience : Goldman Sachs, Morgan Stanley, KPMG, Oracle & Others I help startups and enterprises ship AI products and the backend systems behind them — from RAG chatbots and LLM integrations to scalable APIs, data pipelines, and production deployments. 10+ years building software. 30+ Upwork projects, all 5-star rated. Expert-Vetted (top 1%). One engineer who can own the problem from architecture to live product — clear communication, on-time delivery, code that scales. WHAT I BUILD AI & LLM • RAG chatbots and knowledge assistants over PDFs, docs, wikis, Notion, and internal APIs • LLM integration with OpenAI (GPT-4o, GPT-4), Anthropic Claude, and Google Gemini • AI agents with tool use — CRM, email, Slack, webhooks — plus guardrails and human approval • Streaming chat UIs with conversation memory, citations, and admin dashboards • LangChain, LlamaIndex, vector search (Pinecone, pgvector, Chroma, Weaviate, Qdrant) Backend & APIs • REST and GraphQL APIs in Python (FastAPI, Django, Flask), Node.js, and Java/Spring Boot • Microservices, event-driven architecture, authentication, and third-party integrations • PostgreSQL, Redis, MongoDB — schema design, optimization, migrations • Data pipelines with Kafka, Spark, and Airflow for analytics and ETL Frontend & Cloud • React, TypeScript, Next.js, Angular — SaaS dashboards and polished product UIs • AWS, GCP, Azure — Docker, CI/CD, monitoring, production hardening WHY CLIENTS HIRE ME Most AI projects break at the seams — weak APIs, messy data ingestion, no real UI, nothing deployed. I deliver the full path: data in → embeddings & retrieval → LLM → API → frontend → cloud.