Veere More photographs
I build software and the platforms it runs on. Away from the keyboard, I make photographs.
I care most about simplicity. An idea only counts once it runs as a system that is resilient, measurable and useful.
I keep learning on purpose, because the work keeps changing and I want to change with it.
See also Ask the site Selected work Tech lineage
Pick a route to my work, experience, photography or notes. You can also type a question about my background; an AI answers it from my resume.
Two projects, each with a write-up, a working demo and the source code.
Transformation and technical coach at De Nederlandsche Bank since February 2024. Before that: independent agile and technology consultant, development manager and acting CTO, and senior developer.
Individual photographs and two black-and-white series.
Short notes on the reasoning behind projects, privacy choices and how I work.
A snapshot of current work, updated by hand.
Typed questions go to an AI service (OpenAI) that answers from my resume and this site, about 10 a minute. Escape cancels a question; / jumps back here.
See also Selected work Tech lineage LinkedIn
Each has a write-up, a working demo, and the source code. Smaller tools follow in the next entry.
Every device on a tile,
every link a line you can follow.
UniFi Network Map turns topology data into an isometric picture of what connects to what, inside the Home Assistant dashboard. Below: the same renderer, drawing a fictional home.
Open source. Home Assistant integration, listed in the default HACS store (the Home Assistant community store).
Infrastructure
Clients
Drawn by the same renderer as the Home Assistant card (unifi-network-maps 2.3.2) from a fictional topology. An interactive illustration, not a live dashboard: no real devices or telemetry.
A list of devices tells you what is there. It takes a map to see how it fits together, and which cable a problem is on.
Render the topology as an interactive isometric SVG inside the dashboard, with VLAN colours on the links and device details one selection away.
Room for the stories
between generations.
Explore family connections, life events, and the patterns that run through them. At your own pace, with your story kept private.
A family tree can hold more than names and dates. Traumatrees makes room for relationships, turning points, and patterns across generations.
Sensitive entries are encrypted in your browser before they reach the server, so your reflections stay yours.
A tool for personal reflection, not therapy.
See also The network map, in full More from the workbench Tech lineage
Smaller tools, each with its source code.
Keeps your shelf on Hardcover in step with what you read on a Kobo e-reader: which books, how far, finished when. Plug the Kobo into your computer and it syncs. Nothing is installed on the Kobo.
It starts as a dry run and never guesses a match: a book it cannot place waits for you to choose. It works with a stock Kobo and books from the Kobo store.
Beta, v0.2.0. Runs on your own computer, or on a home server for a household.
brew install merlijntishauser/tap/kobo-hardcover-sync from unifi_topology import (
Config, build_node_type_map, build_topology,
fetch_devices, normalize_devices, render_svg,
)
devices = normalize_devices(fetch_devices(Config.from_env()))
node_types = build_node_type_map(devices)
gateways = [n for n, t in node_types.items() if t == "gateway"]
topology = build_topology(
devices, include_ports=True, only_unifi=False, gateways=gateways,
)
svg = render_svg(
topology.tree_edges or topology.raw_edges,
node_types=node_types,
)The Python library behind the network map above. It reads devices, ports and client connections from a UniFi controller, builds the topology, and renders it as an SVG diagram, flat or isometric.
It started inside unifi-network-maps and now stands on its own, so the Home Assistant integration and anything else can use it as a library.
v3.2.1 on PyPI. Python 3.12 or newer, MIT licence.
pip install unifi-topology See also Selected work Ask the site
Individual photographs and two series, each with its own way of looking.
See also All photography Verdronken huisjes Islay landscapes
Four decades of platforms, languages, wrong turns, and useful obsessions. Open an era, then a milestone for the story behind it.
The first computer I was allowed to play with.
My dad bought this computer, and I was a kid with a newfound interest in technology and creativity.
Copying 500 lines of code from a book to learn the language.
For loops for the win: move that turtle around.
The first Mac in our family, System 7 as default.
I bought an IBM PC to annoy my dad, but installed Red Hat Linux 4.2 after three weeks, because I hated Windows.
Babysteps in adding features to a website, MySQL as the database.
Formal education in computer science, learning algorithms and data structures.
Standups with myself, pair programming with JP the Goat.
First language I really enjoyed, learning object-oriented programming.
After running servers co-located, someone else was on call for failing disks.
Oh my Containers... so many containers, so little time.
Not touched since computer science classes, but CQRS and event-driven architectures are the bomb with Java.
Inception: have Jenkins deploy K8s with Jenkins on it to deploy applications.
Who needs containers? Serverless computing for scalability and cost efficiency.
Automate all the things!
Transforming a legacy spaghetti codebase into a modern React application: full hands-on development again.
Babysteps with LLMs and accelerated development workflows.
Hue, Zigbee and UniFi: the house finally does what it is told.
Zero-knowledge encryption, 100% commitment.
A Homelab running Proxmox, Traefik and rather too many LXCs. Turns out I missed being the one on call for failing disks.
Past the babysteps: agents that read the repo, write the tests and ship. Reviewing their work carefully is the actual skill.
See also What I build now Now Notes
The Pan Galactic Gargle Blaster was invented by Zaphod Beeblebrox, a major character in Douglas Adams' novel The Hitchhiker's Guide to the Galaxy.
The effect is like having your brains smashed out by a slice of lemon, wrapped 'round a large gold brick.Read the recipe
