# Ernest Mistiaen

> Design lead and maker in the Netherlands. Product designer since 2010 who turns small problems into structural fixes in complex, regulated products: care, energy, finance, telecom, and now AI. Next to client work he designs and builds his own products end to end, including AI products.

Currently open for: Product Leadership, Staff/Principal IC roles, and select freelance projects.
Contact: hi@ernestmistiaen.com · LinkedIn: https://www.linkedin.com/in/ernest-mistiaen/

## At a glance

- Product designer since 2010. First design job at Floorplanner (2010–2015); since then mostly freelance, often the only designer on the team.
- Companies he worked for include NN, T-Mobile, Nedap, Rabobank, Greenchoice, Floorplanner.
- Leadership: set up and led T-Mobile's mobile design system, bringing in and leading two designers; its foundations and principles carried over into the Odido design system. At NN he set up the team's agile way of working and facilitated co-design sessions.
- Research that is fast and cheap: a card sort with 200 people with results within 24 hours (NN); interviews with care workers across sectors (Nedap).
- Strategy: product vision, product strategy and roadmaps cut into small steps, an evaluation plan based on HEART metrics.
- AI: at Nedap he designed an AI feature around something care workers already do (taking notes) instead of adding a chatbot. He also builds AI products himself (see Behind the scenes).
- Systems: design systems (T-Mobile, NN) and information architecture that scales (Greenchoice).
- Works in Dutch and English; this site exists in both.

## Client work

Each case is a full write-up with his role, period, team, contribution and outcome.

- [Nedap: A scribbled note as interface](https://ernestmistiaen.com/cases/nedap/): New AI product. An AI feature for care workers that builds on something they already do every day. Role: Senior Product Designer. Period: Sep 2025 – Jun 2026. Outcome: Experiment with care organisations since Q3 2026.
- [T-Mobile: It started with a list of invoices](https://ernestmistiaen.com/cases/t-mobile/): Mobile app & design system. A list of invoices led to a restructure of the mobile app and a multi-brand design system that outlived the rebrand to Odido. Role: Senior UX Designer, lead of the mobile design system. Period: Jun 2022 – Jun 2023. Outcome: Paused in May 2023 for the rebrand to Odido; its foundations and principles carried over into the Odido design system.
- [Greenchoice: A baker is not a municipality](https://ernestmistiaen.com/cases/greenchoice/): Business customer portal. A business customer portal that shows each customer what fits them, and grows with them from one building to hundreds of connections. Role: Senior UX designer & Strategy. Period: Nov 2023 – Dec 2024. Outcome: Strategy, roadmap and designs handed over in December 2024; the first changes were already made during the assignment.
- [Nationale-Nederlanden: Is it steak or mince today?](https://ernestmistiaen.com/cases/nn/): Personal finance app. A personal finance app built around money streams, on categories that match how people think about their money. Role: Senior Product Designer. Period: Jan 2020 – Apr 2021. Outcome: Launched in May 2026, still recognisable as the design I left behind.

## Behind the scenes: products he designs and builds himself

He ships whole products on his own, from idea to code to launch. Overview: https://ernestmistiaen.com/behind-the-scenes/

- [Fieldgyde](https://fieldgyde.com) (Web app · Live): Interview scripts for teams without a researcher. Product teams know they should talk to their users, but writing a good interview script takes training and time. Fieldgyde asks about your research goal, the people you’ll talk to and your product, then writes the whole script: open questions that don’t lead, follow-ups for each one, why each question is there, and the traps to avoid as an interviewer. Designed and built by Ernest: a Rails app whose AI draws on a library of UX research methods, with accounts and Stripe payments.
- [worthwatching](https://worthwatching.football) (Website · Live): Which Champions League match to put on. A briefing for every UEFA Champions League match, written before kick-off. It tells you what each side actually does, so you know what to look for once the game starts, and gives every match a score out of 10, so you know which one to watch. Designed and built by Ernest: a data pipeline and AI-written previews, with a test after every match that grades each claim a preview made.
- [Crappy Monitor](https://crappymonitor.ernestmistiaen.com) (macOS app · In progress): See your app on your users’ screens. Designers work on beautiful displays; the people using their software often sit at a washed-out office or clinic monitor. Crappy Monitor is a menu bar app that makes your own screen that bad: brightness, contrast, colour, low resolution, with nine presets based on real monitors. Hold Option to see your own screen again. Designed and built by Ernest: a native macOS app in Swift that changes the display itself, signed and notarised by Apple.

## Pages

- [Home](https://ernestmistiaen.com/): introduction, client logos, featured cases
- [Work](https://ernestmistiaen.com/work/): all client cases
- [Behind the scenes](https://ernestmistiaen.com/behind-the-scenes/): his own products
- [Contact](https://ernestmistiaen.com/contact/)
- [Dutch version](https://ernestmistiaen.com/nl/)