Glib S.

Full-stack AI engineer for production SaaS. I build tool-using AI agents, secure RAG, document automation and data pipelines with React, Node.js and Python, and take them from idea or fragile prototype to a product people rely on.

$170K+ earned on Upwork | 2,500+ hours | 5.0 from 32 reviews | 8+ years of engineering

"One of the best AI Engineers we've ever worked with." (Upwork client, 2026)

WHAT I BUILD

• AI agents that use real tools, APIs and internal data, and return cited answers instead of chat demos.
• Secure RAG and knowledge systems: permissions enforced in the database, citations, evaluation and fallback behavior.
• Document AI that turns PDF, Word and Excel files into structured, reviewable data.
• Web scraping and data extraction at scale, with LLM parsing where rule-based parsers break down.
• Complete AI SaaS products: frontend, backend, authentication, billing, admin tools and deployment.
• Rescue work for existing or AI-generated codebases that fall apart past the demo.

RESULTS FROM RECENT WORK

• Partner-discovery SaaS: a Claude tool-use agent that researches and qualifies 10,000+ companies and returns cited briefs.
• Public-records data platform: extraction agents for 28 court jurisdictions across 12 US states; LLM parsing recovered sources the team had written off.
• Supplier document AI: retailer form completion cut from about 8 hours to under 5 minutes (client-published figure).
• Listing automation for an e-commerce seller: saved the client 80–90 hours of manual work every week.
• Property data platform: 2.36M properties linked from 20 government data feeds, with ML valuations at 5.4% median error.
• Mobile app rebuild: after relaunch the product passed 5,000 active users and raised $100K+.

HOW I WORK
I start from the business outcome and the real constraints: your data, user roles, security, latency, cost, and who will operate the feature after launch. You get working increments, direct communication, clear tradeoffs and maintainable code. Based in Ukraine (UTC+3), overlapping with EU working hours and US mornings.

CORE STACK
TypeScript, React, Next.js, Node.js, NestJS, Python, FastAPI, PostgreSQL (pgvector), MongoDB, AWS, Docker.
AI: OpenAI, Claude, Gemini, LangChain, embeddings, vector search, tool calling, structured outputs, MCP, and computer vision when the product needs it.