About

What I do#

I'm Tech Lead Data & AI at yellow arrow, a Dutch MSP. I'm responsible for the technical direction of our Data & AI practice: the architecture we stand behind, the standards we hold our work to, and the people who build it. Day to day that means designing data platforms on Databricks and Microsoft Fabric, putting AI on top of them in a way that holds up in production, and helping the team get better at both.

How I work#

I like systems I can hold in my head. That usually means fewer dependencies, explicit state, and small, well-named pieces that each do one thing. I would rather spend an extra day on a design that makes a class of bugs impossible than spend a week later chasing one of them.

I try to understand at least one layer below the one I work in. Building a compiler changed how I read code, and building an audio engine changed how I think about timing and buffers, even in data pipelines.

As a lead, most of my job is making good decisions easy to repeat: clear standards, honest reviews, and writing things down so the team never depends on me being in the room.

What I build outside work#

I started out in Music Technology at HKU, and I still approach software a bit like composition: small parts, strict structure, and the whole has to hold together over time. In my own time I build things from scratch in Rust: AIRE, a game audio engine published on crates.io; Recolon, a functional programming language with its own compiler. Away from the keyboard I play five instruments.

Contact#

The best way to reach me is email: contact@breijen.com. I'm always happy to talk about data platforms, AI in production, Rust, or anything you read here. You can also find me on GitHub and LinkedIn.