Ondrej Rohon
I work side by side with founders
to turn ideas into real products.
Product thinking, design,
and code.
Ondrej Rohon
I work side by side with founders
to turn ideas into real products.
Product thinking, design,
and code.
Chatsheet
Chatsheet, formerly Find AI, is a New York based AI startup.
I Worked directly with the founder to explore, design, and ship multiple AI products. I took a rough vision, filled in the gaps , product decisions, UI, architecture, and shipped it to production. One was a browser extension that let users summarize pages, fact-check data, ask questions about any text or YouTube video, and send it all into an AI-powered spreadsheet. We worked on several other standalone products under NDA.
Tech stack: SvelteKit, Go, heavy LLM integration, built with Cursor.
Slova
Personal project, focused on product discovery and early validation.
Duolingo doesn't work for students who learn with a real teacher. I started by exploring AI tutoring, but after interviewing 10+ language teachers I kept hearing the same thing: teachers assign homework through lifeless PDFs and dated textbooks that just can't compete with something like Duolingo. Students expect learning to be fun and personalized, and what they're getting feels ancient.
But the problem wasn't that teachers needed to be replaced by AI. It was that nobody was giving teachers better tools. I'm building something I think of as a teacher's exoskeleton, a tool that generates personalized study material for their students, grounded in research from Andy Matuschak, former R&D director at Khan Academy.
Azylo.com
Azylo was a content marketplace for digital publishers.
I joined as technical co-founder to replace a WordPress MVP with a full custom platform -a writing editor for authors, an automated subscription system for publishers, and the UI/UX across the entire product. Built it from the ground up in SvelteKit. The product worked. The business didn't -we never found real product-market fit. It was a hard lesson that taught me two things: even if you join a project late, you have to go back and validate the fundamentals yourself. And choosing the right cofounder is one of the hardest decisions you'll make.
Deepnote
YCombinator funded, Prague based startup. A collaborative data science notebook. I joined as a product engineer and helped transform the codebase from early startup phase to Series A. The file explorer was the biggest performance bottleneck in the product -I rebuilt it from scratch, making the whole code-writing and collaboration experience noticeably faster. I built an end-to-end performance monitoring system with Cypress to catch regressions before customers felt them. I led the migration from Redux to GraphQL across large parts of the product. The result: a codebase the team could actually ship fast from.
Just Circles
Personal project, native iOS app.
A minimalistic, opinionated habit tracker with generous free tier. Pay once & own forever. Calm. No notifications, no subscription, no social features, no streaks, no charts. Just your activities. Track them and review your progress however you like. Subscription fatigue relief guaranteed.
Dusan Husar
A portfolio site for an award-winning cinematographer. The design challenge was finding the right form to present his visual work and making the whole site feel like him -his aesthetic, his taste. The design has to match the quality of work it presents. I designed and built it from scratch. Also built a custom open-source CMS to power it because nothing else had the UX I wanted.