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Comment by SOLAR_FIELDS | Hacker News Reader

These are fun but as long as it’s OpenSCAD it will always be a hobbyist toy and not able to be used for professional use. Which is fine! But imo an openscad rendering pipeline is pretty easy. I’m more interested in someone trying to take a stab at vibe coding models that output Brep compatible formats and generate STEP files. This is much, much harder to do but is the main step towards doing this for actual professional use cases.

Presumably someone is getting closer to this, curious who the most robust player in that space is.

Also curious if building an actual kernel replacement for open cascade is on the table now with AI, it’s a very tough thing to do but now it seems somewhat tractable in 2026

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I have been trying to force LLMs to work with geometries for over a month and it's so hard. Even the best LLMs have an extremely poor sense of geometric relationships in my testing. I would also stay away from mesh based CAD like OpenSCAD and go straight for build123d which operates on real solid models (BREP): https://build123d.readthedocs.io/en/latest/index.html

I recently designed an eval to see if LLMs can produce usable CAD models: https://kerrickstaley.com/2026/02/22/can-frontier-llms-solve...

Claude 4.6 Opus and Gemini 3.1 Pro can to some degree, although the 3D models they produce are often deficient in some way that my eval didn't capture.

My eval used OpenSCAD simply due to familiarity and not having time to experiment with build123d/CadQuery. There is an academic paper where they were successful at fine-tuning a small VLM to do CadQuery: https://arxiv.org/pdf/2505.14646

Great work - looks like building block towards 3d-model composition integration testing. I have been looking for a solution that would allow testing component fit into surrounding components. My use-case would be to create parametric boat hull and then add components to that could be tested for fitness in the arrangement.

I also been trying to use LLM for creating house plans but it got bad sense of directions and spaces and sizes and all.

So I ended up using LLM + a tool which implements hard constraints and gives back validation data to LLM so the LLM can figure out why something wouldn't fit that specific way

Even with AI it is going to be incredibly difficult. Not really a full CAD kernel but I have been at something similar for the last 5 months - https://lilicad.com

Your project looks slick! Is it using Open CASCADE under the hood?

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