Show HN: Open-sourcing our text-to-CAD app

78 zachdive 10 9/5/2025, 5:09:35 PM github.com ↗

Hey HN! I'm Zach from Adam (https://adam.new/). We’re building an AI co-pilot for mechanical CAD software.

As part of our broader research, we built a browser-based Text-to-CAD app (https://news.ycombinator.com/item?id=44182206) and are now open sourcing it. This is a React SPA with a Supabase backend.

What it does:

* Generates parametric 3D models from natural language descriptions, with support for both text prompts and image references

* Outputs OpenSCAD code with automatically extracted parameters that surface as interactive sliders for instant dimension tweaking

* Exports as .STL or .SCAD

Under the hood:

* Separate agents for conversation and code generation; simple parameter tweaks bypass AI entirely using deterministic regex-based updates

* Runs fully in-browser by compiling OpenSCAD to WebAssembly and integrating Three.js with React Three Fiber for 3D rendering

* Supports BOSL, BOSL2, MCAD libraries and custom font support (Geist) for text in models

We’ve seen many developers trying to replicate this kind of functionality, so we’re releasing this to give the community a solid foundation to build on.

Future improvements:

* Expand geometry support - Move beyond CSG primitives to support curved surfaces, fillets, lofts, and constraint-driven modeling through CadQuery/Build123D

* Better spatial context - UI for face/edge selection and viewport image integration to give LLMs spatial understanding

* Enhanced capabilities - RAG on documentation and integration with more OpenSCAD libraries for features like proper threading

You can clone the repo and run it locally! Contributions are welcome, and we’ll keep merging PRs as they come in.

Comments (10)

mclau157 · 3h ago

Readme could really use some pictures

zachdive · 2h ago

will add some!

jstanley · 3h ago

> CADAM uses ngrok to send image URLs to Anthropic

FYI you can send base64 encoded PNGs, no need to mess about with ngrok.

adenta · 3h ago

Yeah, the idea sounds magic, but there’s a lot of weird things going on in this application

I feel like a standalone script would be much more helpful

zachdive · 2h ago

i agree

renecito · 54m ago

do you have examples or any getting started guide to know what can I expect ?

zachdive · 44m ago

what sorts of examples would be helpful? will add screenshots to the readme plus anything else you'd like.

you can also check out the hosted version to see what to expect

bilsbie · 2h ago

Cool project. AI is surprisingly good with openscad. I wonder what a custom trained model could do?

gerdesj · 12m ago

I've had mixed results with Chat n OpenSCAD. For my first effort it used BOSL (good skills) but hallucinated functions (bad skills)! It also failed to allow for closing the geometry properly ie adding a tiny epsilon to get unions and diffs etc to join up.

The model was really simple - a threaded "back nut" - basically a hollow thin walled cylinder with a base with a hole in it. The cylinder is threaded on the inside. Its a plumbing part for a long out of production system that still works fine but its leaking and I broke the current nut trying to tighten it. Once I dissembled the joint it turns out it does not need to be tight just stable. It only serves to hold a tube with two O rings in place inside the water inlet to the device and a standard plumbing nut and olive job on the other end of the short tube. A perfect job for 3D printing. It took me six iterations to get the thread right. At one point I miss-read my calipers sigh

I'd love to see what RAG will do for this with a well focused model. There is a lot of decent documentation for OpenSCAD and a lot of literature for this form of modelling.

zachdive · 40m ago

yes we did a bunch of experiments on this! we could get OS models up to but not beyond any of the best closed foundation models. Gemini 2.5/Claude 4 most reliable as an api option