Redesigning my campervan with Codex

I’ve been wanting to redesign the interior of my campervan. My current setup is a simple timber rock’n’roll bed with a mattress from an IKEA Lycksele Håvet sofa bed. It’s very comfortable, but it takes up the entire cargo area, and switching between bed and seat mode means moving all my stuff around.

I’m in the luxury position of being able to work remotely, so I’ve been dreaming up a layout that makes better use of the space: a narrower bed that’s easier to convert, and more storage in a fixed cabinet unit.

I designed my first van bed in SketchUp, but this time I wanted a different workflow. I do all my software development with Codex these days, which mostly means writing markdown files and babysitting agents. I wanted to work on the van design the same way: “Make the bed 2cm lower”, or “Extend the cabinet so it fits precisely between the rear of the van and the sliding door.”

So I asked Codex to build me a custom CAD app, with a 3D CAD library in the backend and an interactive browser frontend. It uses build123d for the CAD model. I started with measurements from my van and some reference photos, which gave the agents enough to put together a reasonable estimate of the interior. From there, I built up the furniture design step by step.

I can ask Codex to change the design, then look at the result in the browser and work out what needs adjusting next. The current design has a sliding slat bed, a cross bench, a storage cabinet and a folding laptop table. You can explore it in the interactive viewer, including the bed conversion. That’s a snapshot of the design; I make changes in the local app.

It’s also easy to point the agents at my local hardware store and tell them to stick to materials I can buy there. The app creates plywood cut lists and sheet layouts for me, so I can plan what to buy and cut alongside the design.

At this point I’m spending more time messing around with this custom piece of software than building my van, but hey, it’s all fun and games!

The van is empty at the moment. Next up is working out a LiDAR and photogrammetry workflow to build a more accurate 3D model of the interior, replacing my current approximation.

The code is in my campervan repo.