Senior Product Designer

Jana Gonsenicova

I hand over working software, not a spec. From research to merged pull requests, I design and ship time-tracking software at Toggl.

I design for complexity users shouldn't have to see. The underneath still need to account for what can happen, and what happens next.

I map the rules before I draw the screen: what can happen, what happens next, and where those states collide. The interface comes after the logic.

I explore in , then converge and strip.

I don't explore in isolation. I bring developers in right during exploration and pull in PMs and customer-facing teams when their context can change the answer. When something is easier to understand in code, I build it there.

I don't hand off screens. I hand over a with the behaviour specified across states.

Not a Figma approximation — it runs in the production codebase and the team's own design system, with the loading, empty, error and edge states in place. I use AI tooling, MCPs and skills to work directly in the codebase; everything I open goes through the same review as anyone else's. Some of it merges directly; the rest engineers build from and cite in their own pull requests.

I trust over taste, including my own.

The method follows the question: production usage, surveys, interviews, usability testing, churn data. When the evidence disagrees with my solution, the solution changes.

This site is my own build. A pixel Claude taking a whip crack — this one too
The commits are real

Toggl 2.0Toggl 2.0

Goals: designing a state system, not a feature

My role

Senior Product Designer on Toggl Track and Toggl 2.0

Email

Resume

One page, updated 6 Sep 2026

GitHub

608 contributions in the last year

References

8 recommendations

Toggl 2.0Toggl 2.0

The timesheet kept getting more complicated. The interface didn't have to.

Toggl Track

The pattern that outlived my involvement

OROOM

From browsing to booking

Duolingo

1,599-day streak

Jana, smiling, in a black turtleneck against a pink wall

I treat designs like my own home — tidy, aesthetic, and above all functional.

Been

67 countries · 34% of the world

Flighty passport

289 flights · 714,491 km

Mobile app

Toggl 2.0 on iOS and Android

Browser extension

Toggl 2.0 extension for Chrome and Firefox

Q&A

What hiring managers ask me first

Building this site

Rather than designing the portfolio once, I built a system that let me design it.

Prague09:07

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