A psychologist’s eye,
an end-to-end craft,
and AI on the busywork.
I’m Marcin, a lead product designer. I read the behaviour behind the brief, carry work from first principles to shipped detail, and hand the repetitive parts to AI so the judgement stays human.
Selected work
A few pieces that show how I think end to end. Most are kept behind a password while details are tidied — the marker tells you what happens on click.
Accounting Rules Navigator
Locked UnlockedGave finance teams one visual map to configure their own accounting rules — no IT in the loop.
Aptitude Design System
Locked UnlockedOne language across a fragmented suite — tokens, components, and the governance to keep them honest.
Virtual Machines
Locked UnlockedWide-lens research that overturned three foundational assumptions before an expensive build.
About
I design for how people actually behave, not how briefs assume they do.
Before product, I trained in psychology. It taught me to watch what people do under pressure rather than what they say in a workshop, and to treat every interface as a small experiment in attention and trust.
I’m comfortable across the whole arc — framing the problem, shaping the system, and pushing the last few pixels until the thing feels inevitable. I don’t hand off the hard part.
I lean on AI for the repetitive middle: variations, audits, first drafts, boilerplate. The hours go to judgement, not production, and the thinking stays mine.
Mostly I help teams decide. The best work I’ve done looks obvious in hindsight, because the arguments happened early, in low fidelity, where they’re cheap.
Contact
If any of this resonates, I’d like to hear what you’re working on.