berk
01 Berk de Rooij / Amsterdam
Hi, I'm Berk.
I write code
and build things.
Cybersecurity student at Inholland. I write software and work on electronics with PolderLabs.
About
02 About
More than one lane
I spend most days moving between code, a terminal, and a workbench. I like understanding what is underneath a system and seeing an idea work outside a browser.
Security and systems
I study Cybersecurity at Inholland in Amsterdam. What keeps me interested is the point where software meets the system underneath it: networks, permissions, protocols, and the small assumptions that can become real weaknesses.
Building across software and hardware
At PolderLabs and in my own projects, I move between TypeScript, Rust, embedded software, and hardware. I enjoy the full path from a rough idea and breadboard to something another person can actually use.
Agentic tools
Coding agents are one part of that work. I am interested in the practical questions: how they keep context, how you supervise them away from the terminal, and where automation should stop and ask.
Outside the screen
Away from the keyboard, I build and repair FPV drones, tinker with ESP32 boards and electronics, and ride motorcycles. They all reward the same things: attention, mechanical sympathy, and learning from immediate feedback.
A personal note
ADHD is both useful and difficult.
It gives me a lot of curiosity and can turn an interesting problem into deep focus. It can also make prioritising, switching tasks, and finishing the last ten percent harder. Both sides are part of how I work.
03 Work
Selected projects
Flipper Zero boards
Custom add-on boards for the Flipper Zero.
Electronics / PCB designdexyd
A phone interface for coding agents. Check sessions, review changes, and respond to approvals away from the terminal.
TypeScript / Mobile / Developer toolsTimeTone
An ESP32 time clock with a touchscreen and a self-hosted dashboard. It keeps working offline.
ESP32 / LVGL / Next.jsopenwolf
My fork of a project-memory tool for Claude Code, Codex, and OpenCode. Keeps context on your own machine.
TypeScript / Local-first / Forkppexchanger
Encrypted messaging between terminals on the same network, written in Rust.
Rust / Peer-to-peer / LANCaddyUI
A web interface for managing Caddy reverse proxies, certificates, and logs.
JavaScript / Caddy / Self-hosting04 Contact