Identity you can prove, code you can trust.
I'm CTO at Yivi and Caesar Groep. Long, specific writing on privacy-first digital identity and on engineering practice in the age of coding agents.
Selected writing
Lights Out, part 4: the bottleneck moved
Eight times the code, a third faster At AI Engineer New York this month, Laurie Voss , co-founder of npm and now at Arize, put up a number that belongs on every engineering leader’s wall. Teams using coding agents are…
Lights Out, part 4: the lessons learned from configuring a coding agent
Dobby, briefly Dobby is our coding agent, named after the house elf. He is a GitHub App with his own scoped identity, plus the host that runs him. When something arrives, a GitHub event, a Slack message or a scheduled…
Lights Out, part 3: running the nightshift
Meet Dobby We named our agent Dobby, after the house elf in Harry Potter. It was meant as a joke and turned out to be the most accurate architecture decision we made all year. Dobby is tireless, eager to please,…
Lights Out, part 2: old school stays king
Lights Out, part 2: old school stays king On 26 August 2025, someone pushed eight malicious versions of Nx to npm . Nx is a build tool with millions of weekly downloads. The packages were live for five hours and twenty…
Lights Out, part 1: the insane adoption of agentic coding
While You Blinked On 5 February 2026, SemiAnalysis opened a research note with a sentence that should have rattled every engineering manager in Europe: “4% of GitHub public commits are being authored by Claude Code…
Integration patterns using NServiceBus & Azure Functions
At the SeverlessDays Amsterdam online meetup on February the 3rd I gave a talk on Integration patterns using NServiceBus Azure Functions . The slides can be downloaded here The code can be found on Github
Improving your Azure Cognitive Search performance
It can be quite a struggle to really understand the ins and outs of Azure Search, how search results are scored, and how scoring profiles with weights and functions add up. In this blog post I intend to explain the…
Applying an Azure Governance Framework in 10 steps
Cloud Republic - Azure Governance Framework. Every year RightScale, now Flexera, holds a survey to measure the current cloud challenges. This year just like in previous years Managing cloud spend and applying governance…
Running an OpenAI Gym on Windows with WSL
Recently, I have been playing with Artifical Intelligence a little bit. I want to take on this subject a little bit more serious and I was looking for a playground to combine gaming with AI, to make it fun. I came…
Sending e-mails with SendGrid and Azure Functions
In this blogpost I’ll show how to send e-mails with SendGrid and Azure Functions. The goal is to send an email like this, stating in Dutch that some products that people are selling are hijacked. SendGrid in Azure First…