About me.

Who I am

Hi, I'm Rafael — married, two kids, a home-server rack in the office, and a weakness for things you can build instead of buying. Based in Berlin. Languages: German, English, Polish.

Career, short form

I wrote my first program on a Commodore home computer at age eleven — the reason was as banal as it gets: I wanted to play games the machine didn't come with. That turned into a programming itch that never went away.

Professionally, the commercial track came first: apprenticeship as a retail merchant followed by a few years in retail including a department lead role. In parallel and afterwards self-employed — first as an online book seller, then with my own Amazon FBA business. For the reselling I ended up writing the software myself: a C# tool with an EAN scanner for listings, re-pricing, and logistics. Out of that self-employment I drifted further into web development and shipped LAMP projects for customers.

That led into the state-accredited distance learning programme to become a certified software developer (Geprüfter Software-Entwickler, 2009–2011, graded "very good"). After that, a few years as an employee at several companies: first classic full-stack LAMP, then industrial automation with software validation, programme testing, and commissioning. From 2016 onwards in a mixed role of software development, Linux/Windows system administration, and technical support — a breadth that forced me to think from the server rack up to the frontend instead of staying in one layer.

I currently work as a DevOps engineer. Separately and on my own time, I've been deep into AI inference, agent patterns, and eval discipline for years. What you see on this site is the second category: hobby and learning log, not part of my professional work.

What I've worked on professionally

Linux and Windows server administration, Active Directory, terminal servers. Web stack with PHP, MySQL, JavaScript/jQuery/AJAX, later C#, Java, and PowerShell. SQL-deep topics: partitioning, joins, indexing, query optimization. Virtualization with VMware vSphere and Hyper-V. Versioning with Git and SVN. Bugtracking and QA workflows with Bugzilla, Redmine, and OTRS. Industrial software validation and commissioning in pharma and food-tech environments — engineering perspective, no domain details.

What drives me today

Container platforms (Docker, Kubernetes), cloud architectures (AWS, Azure), infrastructure-as-code with Ansible and Terraform, observability with Grafana and TimescaleDB, Python with FastAPI and async patterns. Increasingly in the AI space: agent frameworks, MCP servers, local LLM inference on my own hardware, eval patterns for models, multi-agent orchestration. Topics shift; the joy of building and understanding stacks stays the same.

What drives me technically

Self-hosting first. If data has to go to someone else's cloud, there better be a reason — otherwise it runs locally on my own hardware. Most of my personal projects come from that stance — and the home lab that carries them all: an AI server with two GPUs for container workloads, a separate Ollama machine with an RTX 4090 for serious LLM inference, a Raspberry Pi cluster for reverse proxy, Pi-hole DNS, and smart-home bridge. On top of that run health data in my own Postgres instead of five apps, smart home without vendor cloud, LLM inference for sensitive filings, trading research with honest backtest and live lock, a personal AI content pipeline for short-form video.

How I got into AI

First touches with machine learning around 2018 — small experiments on Nvidia hardware, more curiosity than plan. It got serious around 2024 with local image generation: ComfyUI workflows, Stable Diffusion variants, then training my own LoRAs for specific styles. Since mid-2025 mostly AI coding and everything around it: agent orchestration, MCP servers, memory layers, eval patterns for models, and figuring out what actually holds up versus what just demos well.

How I think

Architecture before tooling, discipline before speed, small honest steps before big promises. I plan via ADRs, write tests gladly, and throw out strategies the moment the data doesn't back them up.

Outside the code

Travel — preferably Southeast Asia. The mix of urban density, landscape, and very different engineering culture there makes every trip a recalibration of what I take for granted.

Music — own production in FL Studio. Long sessions where architectural thinking and hearing pull in the same direction.

AI art with ComfyUI — workflows, custom nodes, model stacking. More engineering practice than gallery ambition, but every now and then something sticks.

Gaming, ever since the Commodore. For a few years also actively modding — mainly for Space Engineers, where I wrote my own mods. Modding is engineering with real users who flag every issue immediately — very instructive.

Plus a stack of unread books on geopolitics, physics, and sci-fi — when I'm not coding, I'm reading.