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.
React Native
React
AI Agent Development
Prompt Engineering
Node.js
TypeScript
Python
PostgreSQL
Next.js
OpenAI API
SaaS Development
Full-Stack Development
Supabase
Flutter
n8n
Generative AI
LangChain
API Development
Software Architecture
Retrieval Augmented Generation
Vadim T.
Nesebar, Bulgaria
$5/hr
5.0
1 jobs
Hello there! 👋
Full Stack Development more than 2 years.
My Stack is React.js, Next.js, Python, Django, Node.js, HTML, CSS, SQL, MySQL, DataBases, FireBase,
I can create any website you want for you. Or if you want i can create just Back end or Fron end. I can also create API and Datebase
I can help you create a website from design concept to a completed, polished and professional site. I can also help maintain and update existing websites.
React Native
React
JavaScript
HTML
JSON
webpack
CSS
Python
Node.js
Firebase
SQL
Database
Next.js
Django
Yauheni T.
Sofia, Bulgaria
$15/hr
5.0
4 jobs
Software Engineer
✅🗓️ 4+ years experience as a React/React Native Developer
I'm a React and React Native developer willing to improve your business and bring your ideas into reality.
Starting from the UI until delivering a live working app, I can handle any part of the development process.
Focus on quality of code, accurate fulfillment of client requirements
Skilled at team collaboration while working independently in remote projects.
I am available to assist with resolving any issues in your project.
Tech Skills:
✅ Back-end stack: Node.JS, Express.JS.
✅ Front-end stack: React.JS, React Native, Next JS.
✅ Front-end technologies: HTML5, CSS3, TypeScript, JavaScript, Redux, Redux-Saga, three.js.
✅ Front-end frameworks: Webpack, CSS Modules, React Query, GraphQL.
✅ Experience in Databases: MySQL, PostgreSQL.
✅ Area of expertise: Healthcare, Social Networks.
✅ Specific Application Development: Meeting Application for MS Teams, Video Editor in web, Viewer for Surgical Model
Soft Skills:
✅ Able to quickly learn and apply new technologies.
✅ Development for me is a challenge where I am capable of creating complex projects and find the best solutions.
✅ Focus on quality of code, accurate fulfillment of client requirements
✅ Open for support 8 - 12 hours a day.
✅ Self-motivated and proactive, with demonstrated creative and critical thinking capabilities
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