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mono-api-agent
RAG agent over monobank's official OpenAPI specification: chunking per method, hybrid retrieval and a deterministic hallucination check instead of an LLM judge.
View projectOpen to junior roles in data and AI engineering · remote or in Bavaria
Data & pipelines · AI agents · AI-assisted
Data preparation · RAG & retrieval · automation · Python
For about three years I have worked daily with data that is dirty, constantly changing and still has to be processed. That turned into a working method: measure before claiming anything, and rebuild when the measurement comes back bad. My core project is mono-api-agent — a RAG agent over an official OpenAPI specification, built in one day and rewritten twice that same day because the numbers demanded it. I have not trained models in production — that is the area I want to learn.

Selected projects
The flagship: a public Playwright test suite that checks this very website in CI — 56 checks across desktop and mobile. Alongside it, four product demos from more than 20 personal projects; every demo can be tried directly in the browser.
View the test suite on GitHub
01 / 06
RAG agent over monobank's official OpenAPI specification: chunking per method, hybrid retrieval and a deterministic hallucination check instead of an LLM judge.
View projectPractice & growth
Three years of daily automation practice — more than 20 projects, over 100 scripts and, since 2026, a public e2e suite in CI. With an honest view of strengths and knowledge boundaries.
2018 — 2022
Degree from the State University of Trade and Economics (Kyiv) — mathematical modelling and information systems, recognised by the ZAB as equivalent to a German bachelor (03/2025). Followed by 1st place among ~6,000 participants in the RS School / EPAM JS/FE Pre-School course.
Foundation: degree · EPAM RS School top 12023 — today
Built and operated my own projects daily, consistently on data that was dirty and constantly shifting. Verification, DevTools and my own traffic analysis — 20+ projects, 100+ scripts and workflows, kept reliably in operation over months.
Focus: messy data · verification · reliability2026
Built and published mono-api-agent: a RAG agent over monobank's official OpenAPI specification, created in one day and rewritten twice that day because the measurements demanded it — chunking per method, embeddings over the method's purpose, a deterministic hallucination check (60 s → 2.8 s, five model calls → two). I am looking for a junior role where I can develop this further inside a team.
Goal: data quality, retrieval, applied AIAbout me
After my degree in Economic Cybernetics (ZAB-recognised bachelor, meaning mathematical modelling and information systems) I finished 1st among roughly 6,000 participants in the RS School / EPAM JS/FE Pre-School course. It is the only number about me that can be verified in a second — and mostly it says one thing: I learn fast when I have something concrete in front of me.
Since then I have spent about three years working daily on my own software and automation projects — AI-assisted: I define the requirements, drive coding agents, verify the result and debug through DevTools and network traffic analysis. The input data was never clean and rarely stable. 20+ projects and 100+ automated workflows, kept reliably in operation over months. When an unstable workflow costs money directly, verification becomes a habit.
Today I am pointing that combination at data and AI engineering. My core project is mono-api-agent: a RAG agent over monobank's official OpenAPI specification, built in a single day. Chunking per API method instead of by character count, embeddings computed over the method's purpose instead of the full chunk, a deterministic hallucination check instead of an LLM judge. That same day I rebuilt twice what already worked, because the measurements showed it worked badly. I have not trained models in production — that is the area I want to learn.
Data preparation & cleaning · Spotting broken and incomplete records · Format conversion & validation · Python for automation and scripting · Running pipelines under shifting inputs
RAG: chunking strategies, embeddings, vector search · Hybrid retrieval (lexical signal over vectors) · Deterministic checking instead of an LLM judge · Multi-agent workflows (LangGraph) · Prompt & context engineering
Playwright (public E2E suite) · Browser automation · DevTools & network analysis · Git / GitHub Actions (CI) · Failure analysis & recovery
Reading and interpreting metrics · Interpreting training curves · No models of my own trained in production · Current learning focus
Contact
I am open to junior roles in data and AI engineering or an initial technical conversation.
oleksandr.o.shevchenko@gmail.com