Production domains
Energy, fintech, IT services
Experience across data-heavy and high-stakes environments where correctness, uptime, and maintainability matter.
Limited availability — open to conversations
I build backend systems and APIs in Python. I occasionally work on AI tools and frontend — when the project needs it.
Working context
The strongest signal I can offer right now is not a polished slogan but the kind of teams and systems I've worked in: research analytics, fintech, and production backend delivery.
Production domains
Energy, fintech, IT services
Experience across data-heavy and high-stakes environments where correctness, uptime, and maintainability matter.
Ownership style
Architecture to deploy
Comfortable taking work from ambiguous problem definition through implementation, cleanup, and production rollout.
Engagement model
Remote-ready B2B in Europe
Clear communication, registered sole proprietorship in Poland, and a working style that fits remote product and engineering teams.
Recent team projects
Energy Aspects
Python Developer
Research analytics and internal tools for institutional energy-market products.
JIT Team
Senior Python Developer
Backend APIs, integrations, and delivery in a software-house model.
Equiti
Python Developer
Brokerage and fintech systems in a regulated, high-availability environment.
Projects I'm comfortable putting my name on.
Solo Full-Stack Engineer & Product Owner
Problem: No existing tool could consolidate Polish investment accounts (IKE, IKZE, OIPE, Finax) together with foreign stocks, ETFs, crypto, and precious metals into a single accurate dashboard.
Solution: Built a full-stack portfolio tracker from scratch — FastAPI backend with FIFO cost basis calculations, three market data providers, multi-currency reconciliation, and a React dashboard that shows everything in one place.
Live production app at investtracker.eu. The only tool that correctly consolidates Finax transactions with Polish tax-advantaged accounts and international holdings into one accurate P&L view. Active development continues — potential SaaS release planned.
Solo Full-Stack Engineer
Problem: The studio needed a premium website that converts local traffic in Tricity, supports bilingual content, and performs well in SEO, AI discovery, and trust signals.
Solution: I delivered a complete Astro website with bilingual UX, strong technical SEO, GEO/AEO readiness, high mobile performance, and a measurable audit-driven optimization process.
Production launch at demarestudio.com with strong scores: SEO 97/100, Speed 93/100, AI Ready 100/100, Indexing 100/100, GDPR 100/100 (Dr Strona snapshot: 2026-04-10).
The areas where I can take ownership from first line to production.
Production-grade Python services built to last: FastAPI, SQLAlchemy, async patterns, clean architecture, tests, CI/CD. Opinionated about maintainability.
REST API design, async data pipelines, PostgreSQL, Redis, multi-tenant systems. Comfortable reasoning about scalability and making architectural tradeoffs explicit.
Python workflows that replace manual, error-prone processes. Celery, scheduled jobs, API integrations, data pipelines. Built to run unattended with clear observability.
RAG pipelines, LLM agents, document intelligence, structured extraction. Practical tooling built as part of a larger system — not standalone demos.
When the product requires it: Next.js, React, TypeScript, Tailwind. Not a designer, but builds interfaces that work well and don't embarrass the backend.
I'm a Python developer with a background in backend engineering, financial systems, and automation. I've worked in energy market intelligence, fintech, and IT services — mostly building the kind of software that handles real data and real edge cases.
My primary tool is Python. I occasionally work with AI/ML and React when the project calls for it, but backend systems and APIs are where I spend most of my time.
Notes from building real systems, not theory.
LLM demos are easy. Production LLM apps are not. Here's what I've learned shipping several of them — the problems nobody talks about in tutorials.
15 November 2024 · 3 min read
Not the patterns from the docs — the ones that have actually held up in production, across multiple projects with real teams maintaining them.
3 October 2024 · 3 min read
Most automation projects fail not because of technical problems, but because they solve the wrong thing. Here's how to identify what's actually worth automating.
10 September 2024 · 3 min read
Short version
Useful context for people who want to quickly judge whether I'm a good fit for the work.
Latest content update: 15 November 2024
Primarily Python backend work, APIs, automation, and data-heavy systems. I also work on AI tooling or frontend when it genuinely helps the product.
The strongest fit is work that needs a backend designed or cleaned up, APIs shipped, processes automated, or a production system made more maintainable.
Yes. I work remote-first and operate as a registered sole proprietorship in Poland, so B2B collaboration is a natural setup.
No. I can step into a larger delivery or a narrower piece of work such as a technical audit, backend stabilization, API design, or a targeted automation project.
Limited availability for new work — happy to talk about future collaboration.