CadQuery is an open-source Python library for building 3D CAD models

by gregsadetsky on 4/14/2026, 11:20:39 PM

https://cadquery.github.io/

Comments

by: fxff

At the time of writing this there are 24 comments, of which 4 promote alternatives. I feel that recently the number of shameless plugs and check-out-my-SaaS's surged drastically<a href="https://news.ycombinator.com/item?id=47803846">https://news.ycombinator.com/item?id=47803846</a> <a href="https://news.ycombinator.com/item?id=47803475">https://news.ycombinator.com/item?id=47803475</a> <a href="https://news.ycombinator.com/item?id=47802988">https://news.ycombinator.com/item?id=47802988</a> <a href="https://news.ycombinator.com/item?id=47803416">https://news.ycombinator.com/item?id=47803416</a>

4/17/2026, 9:25:38 AM

by: gcr

Here's an example!I recently used their sister library (build123d, same devs) to build a rotary slide rule bracelet for multiplying three-digit numbers. It was a great experience and wouldn't generally be easy to do with Fusion 360. My bracelet gets quite a lot of comments when I wear it in public. :-)Here's an IPython notebook with lots of pictures so you can see how the different operations come together: <a href="https://github.com/gcr/sliderule-bracelet/blob/main/version-3.ipynb" rel="nofollow">https://github.com/gcr/sliderule-bracelet/blob/main/version-...</a>build123d is quite different stylistically from cadquery, but this should give you the flavor of programming-oriented CAD at least.

4/17/2026, 3:25:51 AM

by: hgoel

CadQuery and build123d have been very handy for prototyping stuff for 3d printing. AI still isn't quite good enough to generate correct scripts, but AI autocomplete at least helps with putting together small snippets.My last project involved making a cosplay helmet. I modeled the shell in blender, it was a low poly design, so I exported it to an OBJ, then put together some Python to load the OBJ, give the triangles some configurable thickness etc. Then I used it to explore how to print the helmet in such a way that the outer surface would be too clean to tell it's FDM printed, without needing to do any sanding.Initially I explored having cadquery put a number on the back of each triangle and I'd assemble it like a puzzle, but that didn't work out. Eventually I figured out how to cut it up into parts that would also eliminate the need for painting and outer surfaces would be clean, and because it was in code, changing which part a triangle belonged to was a matter of moving the corresponding index into another list.I probably could've managed it all in blender too, but being much more comfortable with code, it was easier for me to play with normals and manually turning each piece into a solid.I also go for it for functional designs because, again, tweaking code is more comfortable to me than dealing with constraints and sketches and multiple planes in, say, FreeCAD.

4/17/2026, 3:02:17 AM

by: maouida

CadQuery was an inspiration when I built FluidCAD. I wanted the workflow to be as close to traditional CAD as possible with more interactive UI.<a href="https://fluidcad.io" rel="nofollow">https://fluidcad.io</a>

4/17/2026, 8:51:45 AM

by: jetter

If you like this, you should definitely check modelrift.com which allows to build awesome cad models thanks to OpenSCAD and smart AI assistant.Community built examples: <a href="https://modelrift.com/models" rel="nofollow">https://modelrift.com/models</a>

4/17/2026, 7:46:26 AM

by: ozmaverick72

Interesting. I have played with OpenScad a bit. This looks similar - i guess the difference is the syntax is python - any other major differences

4/17/2026, 2:16:28 AM

by: atoav

I used cadquery to programmatically generate 3D models for an electronics library for a 1000 or so parts that only differ slightly in their measurements. It literally saved me days of manual work.

4/17/2026, 9:30:51 AM

by: girishso

Came across a similar tool replicad. <a href="https://replicad.xyz/" rel="nofollow">https://replicad.xyz/</a>Anyone has used it?

4/17/2026, 6:22:19 AM

by: ponyous

Another library I have to integrate and benchmark against OpenSCAD for my AI SaaS[0]. I am really curious how constructive solid geometry compares to sketching and extruding that CadQuery is build on.Anyone curious in the writeup? I have a pretty good harness for evaluating 3d generation performance.[0]: <a href="https://grandpacad.com" rel="nofollow">https://grandpacad.com</a>

4/17/2026, 7:35:29 AM

by: ginko

Guess this is a good opportunity to plug the DIY trackball I made using build123d:<a href="https://github.com/ginkgo/trackball/" rel="nofollow">https://github.com/ginkgo/trackball/</a>

4/17/2026, 6:37:34 AM

by: lutusp

I create CAD instructional videos based on SolveSpace, and I sometimes try to get people interested in CADQuery as well, but many people interested in CAD will learn SolveSpace or another similar design program, but don't have the programming background for CADQuery. Too bad -- in many ways, for many projects, CADQuery gives better results, especially if a single design needs to be recreated in a range of sizes.

4/17/2026, 5:56:06 AM

by: colechristensen

Neat!I'm working on a CAD kernel in Rust with a frontend either as a Blender plugin or a Blender fork (leaning towards fork at this point) It's not at all ready but I have reached first part status (before going back and rewriting a large chunk of the kernel)

4/17/2026, 2:51:30 AM

by: jiusanzhou

[dead]

4/17/2026, 7:02:42 AM

by: kevinten10