Morten Haraldsen · ethlo
25 years of building software that runs in production — and a habit of building everything else, too. Open source, side projects, and hardware that talks to software.
25 years in production Open source AI Polymath
Selected work
All of it public on GitHub — read the code, not just the claims.
The gateway that remembers every request.
Routes traffic to your services and records every exchange — metadata, headers or full bodies — to memory-mapped files on local disk, with secrets stored only as fingerprints. Configuration is checked before it serves a single request.
One local page for what needs you at work.
Reviews, PRs, Jira tickets, mentions, today's meetings and a stand-up summary — with a sandboxed Copilot chat beside it. Runs on your own machine with your own logins, and keeps nothing anywhere else.
Libraries & tools
Notes
Write-ups of things I've built — software, hardware, and where the two meet.
Coming soon · Hardware · ESP32 · Smart home
Custom differential-pressure, moisture and CO₂ sensors on ESP32s, feeding my smart home for logging — and for adjusting the ventilation itself. Not your typical software project.
How I work
The hardest problems rarely sit inside one specialty. They live in the seams — between the code, the build, the infrastructure and the AI someone bolted on last quarter. I've spent a career working across all of them.
A quarter-century as a professional developer. Deep in Java and the JVM, at home across the whole stack — from architecture to production.
Code in the open, used by other developers — from JSON Schema tooling to the date-time parser inside other people's validators.
Hands-on with AI as a working tool — in code, pipelines and day-to-day workflow. Experience is what makes it fast: knowing when it's right, and catching it when it isn't.
Software is one system among many. Embedded electronics and sensors, automation, CNC machining, building physics — I learn things all the way down.
Off the keyboard
When I'm not at a keyboard, there's often a camera involved. The latest from YouTube.
1:8 Off-Road Buggy Nationals 2025 - Crashes, Speed & Glory
Bumblebee on Rhododendron – A Quiet Moment in the Garden
What Holmestrand Marathon 2025 Feels Like! 💪🎉
Machining unique functional gear coasters on tray. Watch till the end!
Nissan Leaf ZE1 - Brake service with HACK for retracting electric parking brake cylinder!
Plywood scrap challenge with my son 🫣🤗
About
Software developer and architect. My work ranges from mapping business processes to low-level software and data optimisation — for the last 17 years as a principal engineer, where I started as employee number one.
Away from the keyboard: cameras, the workshop, and the occasional sensor wired into the house.
ethlo used to be my company name and has stayed with me ever since. It comes from the Linux ifconfig output, which usually lists eth and lo as the standard network interfaces. Short and sweet, so I sign the things I make with it.