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AI SaaS architect, senior full-stack developer, AI developer, and automation expert. I build LLM/RAG systems, AI agents, agentic workflows, ChatGPT and OpenAI integrations, and production SaaS platforms that ship in 2–4 weeks. No prototypes. No disappearing after handoff. Founders and CTOs don't call me first. They call after the offshore agency delivered a half-working prototype. After the generalist ran out of depth. When the stakes are too high to get it wrong again — that's when they call me. I work like a technical co-founder: I understand your business problem as clearly as the technical one. No account-manager layer, no junior handoff. You work directly with senior engineering across architecture, implementation, deployment, and the post-launch fixes that real systems always need. Over 70% of clients come back for another engagement — because trust is easier to earn through delivery than through proposals. 📈 PRODUCTION RESULTS ✅ n8n + GPT-4 replaced a 12-person workflow — 10,000+ records/day at 99.2% accuracy, saving $380K/year. Shipped in 3 weeks. ✅ Flutter + Node.js fintech SaaS processing $2M+/month — 3 years ongoing, same client. ✅ React + LangChain legal AI tool — cut attorney document review time by 73%. ✅ Next.js + Supabase multi-tenant SaaS with Stripe — zero to $45K MRR in 5 months. ✅ Cross-platform Flutter app — 50,000+ active users across iOS, Android, and desktop. ✅ OCR + GPT-4 + LangChain document pipeline for logistics — 8x throughput, same headcount. ✅ HIPAA-compliant clinical RAG system — delivered in 5 weeks. ✅ Loan-decision latency cut from 4.2s to 280ms for a Series-A lender. ✅ Author of ngx-mask — 2M+ monthly npm downloads, used in fintech, healthcare, and enterprise SaaS worldwide. 🛠️ WHAT I BUILD → LLM/RAG features — OpenAI, Claude, Gemini, ChatGPT, RAG pipelines, AI agents, multi-agent systems, agentic workflows, semantic search, vector databases, embeddings. Evals, latency, observability, fallback paths included. → AI SaaS platforms, MVPs & PoCs — multi-tenant architecture, Stripe billing, RBAC, onboarding, analytics, CI/CD. From validated PoC to production-grade platform without rebuilding from scratch. → AI workflow automation — n8n + LLM pipelines replacing manual ops, copy-paste, spreadsheet cleanup, CRM updates. Human-in-the-loop review flows. 10,000+ records/day at 99%+ accuracy. → Cross-platform apps — Flutter developer, React Native developer, Expo. iOS, Android, web, and desktop from one codebase. Real backends, auth, payments, analytics. 50K+ users delivered. → Production backends — Node.js developer, NestJS, FastAPI, Next.js API routes, Supabase, PostgreSQL, event-driven architecture. Fintech, legal tech, healthtech, logistics — compliance-ready from day one. → Codebase rescue & audit — stalled builds, prototype rewrites, architecture reviews. Salvaged a $200K stalled build in 3 weeks. 🏭 INDUSTRIES → FinTech AI — underwriting automation, payment flows, real-time risk scoring, compliance-ready backends. → HealthTech AI — HIPAA-compliant RAG, clinical document processing, patient-facing AI workflows. → Legal AI — contract review, document intelligence, LLM-powered research tools. → Logistics & E-commerce — OCR pipelines, routing automation, AI-powered search, inventory automation. → RevOps & Enterprise SaaS — AI lead scoring, CRM automation, multi-tenant platforms, developer tooling. ⚙️ TECH STACK 🤖 AI/LLM: OpenAI API · ChatGPT · Claude API · Gemini · GPT-4 · LangChain · LangGraph · LlamaIndex · Pinecone · pgvector · RAG · Prompt Engineering · Vector Search · Embeddings · AI Agents 🖥️ Frontend: React developer · Next.js developer · TypeScript developer · Angular · Tailwind CSS · Flutter developer · React Native developer · Expo 🔧 Backend: Node.js developer · NestJS · Python developer · FastAPI 🗄️ Databases: PostgreSQL · Redis · MongoDB · Supabase · Firebase ☁️ Cloud: AWS · Docker · Kubernetes · GitHub Actions · Vercel · CI/CD ⚡ Automation: n8n · Make · Zapier 🚀 WAYS TO START → AI SaaS PoC in 72 hours — validate before committing full budget. Fixed scope, fixed price. → MVP in 2–4 weeks — production-grade from day one. Not a prototype. → LLM/RAG system in 2–4 weeks — production-ready, not a demo. → SaaS web app — Next.js developer + Supabase + Vercel, Stripe, auth, RBAC, CI/CD. → AI automation pipeline — n8n + LLM replacing manual ops. Shipped and running. → Codebase rescue — stalled build, architecture audit, prototype rewrite. → Architecture consultation — 60-min deep-dive into your AI strategy or SaaS system design. 🚫 NOT THE RIGHT FIT IF YOU need execution without architectural thinking, are optimizing for the lowest rate over ROI, or want someone who disappears at handoff. 📩 READY TO BUILD? Send me what you're building, where you're stuck, and what done looks like. I'll respond with the right questions, a proposed architecture, and clear next steps — usually within a few hours.

Scaling an enterprise application requir​​es more than just a coder; it demands an architect who understands how to bridge high-load systems with seamless user interfaces. With 16+ years of engineering experience and a decade focused on the Node.js ecosystem, I help companies build resilient, business-ready solutions. As a seasoned Full Stack developer and Senior Node.js developer, I specialize in taking ownership of complex digital products, ensuring your infrastructure is built to scale alongside your business. 🏆 𝐏𝐑𝐎𝐕𝐄𝐍 𝐓𝐑𝐀𝐂𝐊 𝐑𝐄𝐂𝐎𝐑𝐃: • 2,000+ hours on Upwork as a Node.js developer delivering elite-level architecture. • 100% Job Success Score (JSS) as a lead backend developer on complex cloud engineering tasks. • Expert-level NestJS & Node.js skills for building production-ready APIs and microservices. • Extensive experience as a Full Stack developer, seamlessly integrating high-performance React frontends with robust Node.js services. 💎 𝐓𝐀𝐑𝐆𝐄𝐓𝐄𝐃 𝐃𝐎𝐌𝐀𝐈𝐍 𝐄𝐗𝐏𝐄𝐑𝐓𝐈𝐒𝐄: • FinTech & SaaS: Expert in building secure Node.js payment flows and reward systems (Stripe, Plaid). Experienced as a backend developer creating automated bank document verification engines. • E-commerce & Retail: Built large-scale retailer networks and management apps where I acted as a • Full Stack developer to ensure perfect harmony between React dashboards and server-side logic. • Cloud & Infrastructure: Specialist in AWS/GCP migrations. I ensure that every Node.js developer on the team follows best practices for Serverless (Lambda) and Monorepo architectures. 🛠 𝐓𝐄𝐂𝐇𝐍𝐈𝐂𝐀𝐋 𝐒𝐓𝐀𝐂𝐊: Backend: Node.js (NestJS, Express), TypeScript, Microservices. Frontend: React, Next.js, Redux (delivering a complete Full Stack developer approach). Cloud (AWS/GCP): Deployment on Lambda, S3, EC2, SQS, and BigQuery. Databases: PostgreSQL (TypeORM), MongoDB, DynamoDB — all optimized for Node.js environments. 💼 𝐑𝐄𝐀𝐋 𝐁𝐔𝐒𝐈𝐍𝐄𝐒𝐒 𝐕𝐀𝐋𝐔𝐄: As a backend developer, I don't just "make it work"; I design systems for High-Load and global traffic. My background in React allows me to understand the data requirements of modern interfaces, preventing bottlenecks before they happen. Whether you need a dedicated Node.js developer for a specific module or a Full Stack developer to lead a full-cycle project, I bring a professional, security-first approach to the entire development lifecycle. Looking for a Senior Partner to take ownership of your Node.js ecosystem? I am available for long-term collaboration. 📩 𝐈𝐧𝐯𝐢𝐭𝐞 𝐦𝐞 𝐭𝐨 𝐲𝐨𝐮𝐫 𝐣𝐨𝐛, 𝐚𝐧𝐝 𝐥𝐞𝐭’𝐬 𝐝𝐢𝐬𝐜𝐮𝐬𝐬 𝐲𝐨𝐮𝐫 𝐚𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐞 𝐭𝐨𝐝𝐚𝐲!

Hi! 👋 Here is what happy clients have said: 🚀“His commitment to clear communication and technical mastery makes them an excellent choice for any organization.” Justin Ramsey, blockovia.com 🚀“Overall, Viktor has been an invaluable asset to our team, and we are deeply grateful for their contributions. I highly recommend them!” Jake Fox, decentral.games 🚀“We had a fantastic review call where he provided context and the specific steps he would recommend we take to ensure PlayerMint had the highest degree of security.” Aidan Rankin-Williams​, playermint.com What you get: ✅Stellar documentation. ✅Comprehensive step-by-step guide on how to use the software. ✅Blazingly fast performance. ✅Daily updates ✅Up to 3 months of maintenance. 🛡️Security updates. Technology stack: 👉Languages: JavaScript, TypeScript 👉Backend: Node js, Deno Express, Nest js, Strapi, Ghost (headless CMS) 👉Devops: Docker, Nginx, Apache, AWS, Linux (Ubuntu) 👉Source control: Git, GitHub, GitLab 👉Build tools: Webpack, Vite 👉Databases: MySQL, Postgress, MongoDB 👉Frontend: React/Next js/Vue, Tailwind CSS, Bootstrap, Redux 👉Blockchain: Solidity, Ethers.js, Forge/Hardhat. 👉Other: Discord and Telegram bots. Contact me now to turn your plan into reality with ease!