Hi, I'm Jonathan.
Data-driven designer with PM skills (6y+).
I believe the fastest way to learn is to ship, track & iterate, and now I use AI to shorten that loop even more.
Based in Luxembourg, open to relocate.
Selected work
Regis
Built a rental tax SaaS for Luxembourg landlords on one rule: capture every invoice as it arrives, never scramble at tax return time again
Solo-built SaaS that captures invoices and bank statements as they arrive, keeps a human in control of every figure, and prepares the Luxembourg form 190 per property. Built for a thirty-year family portfolio first, now in alpha with nine landlords.
Fake-door website design
Designed and built a fake-door test for a founder: three ad-matched landing variants and one tracking chain from Pixel to Notion
A fake-door test of a digital legacy product on Meta ads: three design variants matched to their ads, one measurement chain across Meta Pixel, Conversions API, PostHog and Notion, and the honest read of the data that closed the test and became a public template.
TotalEnergies / Digital Factory
Revamping a power plant monitoring SaaS to increase kWh tracked per operator by 23%
Redesigned an industrial monitoring SaaS used by 9 control center operators managing 350+ energy assets. Through field observation, usability testing in production, and collaborative co-design workshops, delivered a responsive dashboard that increased kWh tracked per operator by 23%.
BforBank
Designing the onboarding flow that ranked #1 on Google's UX Benchmark 2023
Built a fully compliant banking onboarding for BforBank's complete app relaunch. Meeting all KYC, security, and regulatory constraints while achieving a full account opening in under 10 minutes.
Spie Batignolles
Designed the app that connects construction site crews to a complex ERP, replacing 3 legacy tools
Two designers inside a ten-person ERP implementation team. Mapped the on-site ecosystem, ran alignment workshops with foremen and site managers, and shipped one interface for four modules: hours, equipment, material orders and procurement. Twelve site users rated it 83 on the SUS.
Check my personal projects on GitHub
01. AI productivity system
Give your agent a memory: goals, projects and tasks in local Markdown, with an in-app custom dashboard to visualize your data.
02. Product and design second brain
A product and design knowledge base that answers with cited sources and specialized agents.
What my managers and clients say about me
“Strongly autonomous during the discovery phase on highly complex technical and strategic topics. During the build phase, seamlessly integrated into squads and adapted to diverse operational environments. A dedicated team player, highly receptive to feedback, and a positive driving force within a 20-person Design Studio. Also acted as a committed mentor to junior consultants, possessing all the core qualities for a highly successful career.”
“Jonathan was a pleasure to work with. He delivered three custom landing pages really quickly, while keeping the technical side simple for me, Meta Pixel and PostHog tracking included. I also liked that he went further than the brief and proposed a system I now use on my own, plus a few design tricks to increase conversion.”
“J'ai eu le plaisir de travailler avec Jonathan sur la conception de mon site, et je le recommande sans hésitation. Au-delà de l'aspect technique, il a vraiment su s'imprégner de ma vision et la traduire avec justesse, tout en étant force de proposition et en challengeant mes idées quand c'était pertinent. Grâce à sa créativité et son regard stratégique, le résultat final dépasse largement ce que j'avais imaginé au départ.”
“Jonathan m'a aidé à clarifier et matérialiser ma vision produit alors que j'étais bloqué sur ces aspects. Accompagnement de qualité, livrables détaillés et professionnels, délais respectés. Une collaboration fluide et agréable. Je recommande sans hésitation.”
Hiring? Let's talk.
Currently interviewing for full-time product design roles.
Open to relocation, including Singapore, Bangkok and Dubai.
Also open to short freelance engagements: see my Malt profile.