MJ.OLDAK · AI Practitioner

Marcin J. Ołdak

AI & Automation Consultant

Autonomous AI agents · n8n workflow automation · LLM-backed apps — from PoC to production.

01 · About

I ship working things.

Not slides, not past tense — live demos you can try on this page.

I've been exploring AI since 2022 and turned it into my profession in 2026 with MJ.OLDAK — my AI consulting practice. Out of dozens of experimental agents, I brought 4 products to production-ready for small businesses: invoice OCR, an email assistant, a tax-deadline agent and a report generator.

My daily toolkit is LLMs in practice — Claude (API + Claude Code), Gemini — and n8n workflow orchestration, including a production pipeline exposed as an MCP tool for AI agents.

Lately I've gone deeper on the data side — SQL, reproducible analytics pipelines and source-cited reporting on public datasets (see the analysis below).

My background is unusual on purpose: business psychology sharpens discovery and designing around the user's mental model; law makes GDPR, human-in-the-loop and ethical AI second nature — designed in from day one, not bolted on.

Since 2022 I've also worked inside a large international corporation — a 100% English-speaking, heavily regulated environment where I automate repetitive work bottom-up.

4+
production-ready AI products
2022
working with AI since
3.7y
English-only corporate env

02 · Work

Don't read it — try it.

Four AI products I built for small businesses, as interactive demos.

Everything below runs in your browser on sample data — no sign-ups, no tracking. The production versions run on FastAPI + Claude API and are deployment-ready for Polish accounting offices.

Live · production

Sales Agent B2B — live demo

A real, deployed app: form → GenAI lead classification (HOT/WARM/COLD with reasoning) → database with row-level security. GDPR Art. 22 compliant.

Open demo.mjoldak.pl ↗
Agentic infrastructure

n8n pipeline as an MCP tool

Production n8n workflow (Webhook → Gemini → Supabase EU Frankfurt), green end-to-end and exposed via the Model Context Protocol — so AI agents can call it as a tool.

Webhook → LLM → Parse → DB (EU) · instance-level MCP
Problem

Single-task automations break the moment reality gets messy — and nobody sees why.

Solution

An autonomous agent that plans, calls tools, recovers from failures — and shows its reasoning at every step.

Effect

End-to-end process handled. Supervised, not hands-off: a human makes the final call.

Agent Mission Control
Watch an AI agent work
Pipeline
Webhook intake
n8n · webhook
OCR extraction
Azure DI + Claude
Validate tax ID
checksum + registry
Post to ledger
Supabase EU
Draft confirmation
Claude
Human approval
you · the gate that ships
Agent log — live
$ Pick a scenario and hit „Run agent" — you'll see the agent plan, call tools, hit a real-world failure and recover from it. Right here in your browser.

Scripted simulation mirroring my production architecture (n8n Webhook → LLM extraction → validation → Supabase EU → human approval) — including how agents should fail and recover. No external calls; runs entirely in your browser.

Problem

Accounting teams retype invoice data by hand — minutes per document, errors included.

Solution

PDF or photo in → structured data out (Azure Document Intelligence + Claude API).

Effect

An invoice processed in seconds, ready for the ledger.

OCR Invoice Reader
Interactive demo · sample data
Document
FAKTURA VAT
BUDMAT Hurtownia Materiałów Budowlanych Sp. z o.o.
ul. Składowa 18, 53-127 Wrocław
NIP: 899-284-71-63
Data wystawienia: 04.06.2026
Pozycje: cement portlandzki, wełna mineralna…
Extracted fields
Pick an invoice and hit „Process invoice" — extraction runs right here in your browser.

Production version: FastAPI + Azure Document Intelligence + Claude API — PDF/photo in, structured data out. The scanned document is intentionally a Polish invoice — that's what the product reads. Demo runs entirely in your browser.

Problem

Client emails bury accountants — urgent tax-office letters mixed with spam.

Solution

Classification into 5 categories + a drafted reply for each; a human approves before anything is sent.

Effect

Inbox triage on autopilot, replies in minutes.

Email Assistant
Interactive demo · sample data
Inbox — click an email
Classification & reply draft
Open any email — the assistant classifies it and drafts a reply, right in your browser.

Production version: IMAP/SMTP + Claude — classification into 5 categories + reply drafts written in Polish for the client, human-in-the-loop by design. This demo runs in your browser on sample emails (in English for readability).

Problem

Monthly client reports mean hours of repetitive copy-paste work.

Solution

Ledger exports in → branded PDF report out, with KPIs and a written summary.

Effect

Minutes per client instead of hours.

Reporting Agent
Interactive demo · sample data
Client
Month
Pick a client and month, then generate — the monthly report builds right here in your browser.

Production version: FastAPI + openpyxl + fpdf2 — branded PDF reports per client (in Polish), generated from the office's ledger exports. This demo runs entirely in your browser on sample data.

03 · Skills

Stack & methods.

Tools I work with every day — not a logo wall.

01

Agentic AI & LLMs

  • Claude (API + Claude Code) — daily
  • Gemini
  • autonomous agents
  • prompt engineering
  • multi-LLM routing, provider abstraction
02

Workflow orchestration

  • n8n (workflow + MCP tool)
  • Make.com
  • Google Apps Script
  • REST APIs & webhooks
  • modern alternative to traditional RPA
03

RAG & knowledge bases

  • RAG patterns in products
  • knowledge-base design
  • personal Zettelkasten — 270+ concepts
  • AI-ecosystem monitoring (26 sources)
04

Discovery & business analysis

  • Mom Test discovery
  • BPMN 2.0 (AS-IS → TO-BE)
  • user stories, Given/When/Then
  • PRD, ROI modeling
  • compose-vs-build framework
05

Ethical AI & compliance

  • GDPR Art. 22 / 28
  • human-in-the-loop by design
  • EU data residency
  • data privacy & security by default
06

Programming (AI-assisted)

  • Python, FastAPI
  • SQL, Supabase/PostgreSQL (RLS)
  • Azure Document Intelligence
  • Astro, Cloudflare Pages
07

Data analysis & pipelines

  • SQL — JOIN, window functions, reconciliation
  • DuckDB, pandas
  • pandera data contracts
  • DVC — reproducible pipelines
  • data provenance (SHA-256)
  • public data: GUS · Eurostat · NBP · ECB

04 · Open Source

Code in the open.

Don't take my word for it — read the source.

A few public repositories — agents, reusable tooling and reproducible analytics. Each card links straight to GitHub.

05 · Data & Analytics

From data to evidence.

Public data → an audited pipeline → a report that survives scrutiny.

Beyond shipping agents, I do the analyst's core job: find the right public data, reconcile the same metric across independent official sources, benchmark and trend it — and make every figure traceable and reproducible. Here is one finished piece, end to end.

SQL · DuckDB · DVC · pandera Reproducible

AI adoption in Polish enterprises

A GUS × Eurostat reconciliation · 2021–2025

The same indicator — enterprises using any AI technology — reported by two statistical offices, reconciled to within 0.3 points; Poland is climbing fast off a low base, yet the gap to the EU average is widening. Economy-wide data, with the financial-sector caveat stated upfront.

0.34pp
two official sources reconciled (GUS vs Eurostat)
26→31
Poland's rank among EU countries, 2021→2025
−11.6pp
and the gap to the EU keeps widening
Poland vs EU27 AI adoption trajectory, 2021–2025
Fig. 1 · Poland vs EU27 trajectory
AI adoption by firm size, 2025
Fig. 2 · Adoption by firm size (2025)

What it demonstrates

  • SQL — JOIN · window functions · reconciliation
  • Reproducible pipeline (DVC) — one command rebuilds it
  • Data contracts (pandera) — fails loud on drift
  • Provenance — SHA-256 + dataset vintage on every source
  • Honest scoping — limits stated, not hidden

06 · Writing

I write about AI
for business.

Plain-language articles in Polish and English on AI agents, automation, RAG and data — from how a document agent plans its own steps to what the data says about AI adoption in Poland vs the EU. Written for business owners and recruiters, not just engineers.

Browse articles → Polish & English

07 · Contact

Let's talk.

Hiring for an AI / automation role, or just want to see these systems up close? Drop me a message — I reply within 24h.

CV on request — send me a message and I'll reply with a current CV the same day.

© 2026 Marcin J. Ołdak · MJ.OLDAK