About
I'm Leon, a software and AI developer. I design and build websites, web and mobile apps, back-ends, AI features and the automation around them.
My own product is Limosa, a social birding app for web and mobile: logging sightings with photo, sound and video, maps, and AI species identification both on-device and server-side. Designed, built and shipped by me, from database to app store.
A lot of my work revolves around maps and location data. Security and privacy are built in by default, and I also offer them as a standalone review; I've found and reported vulnerabilities in production software including Mozilla Firefox.
By day I'm a scientist at TNO, building secure, interoperable data-sharing infrastructure and EU Digital Product Passports: verifiable credentials, identity and access management, and privacy-first systems. Before that I studied Computing Science (MSc, Cum Laude) with a focus on cryptography, and worked as a full-stack engineer at Simplicate and elgentos.
More on my background: LinkedIn · Google Scholar
What sets me apart
One person, whole stack
You work directly with the engineer who designs, builds and ships: from the first line of code to launch. Nothing lost in handoffs.
Hands-on security & privacy
Demonstrable experience, including real vulnerabilities I've found and reported in production software such as Firefox. Verifiable, not buzzwords.
From concept to production
I've shipped apps full-stack, start to finish, running in production today, not just prototypes.
AI, measured not hyped
I use AI heavily to build faster, but every result is benchmarked and human-verified before it ships. Speed without the broken promises.
How I work
I build things properly the first time: clean architecture, security and privacy by default, automated deployments, and you talk directly to the person writing the code.