CCADAlts

build123d

Pythonic code-CAD framework on the OpenCascade kernel

★ Stars3.5k3,458 on GitHub
Last commit18 Oct 2026
LicenceApache-2.0SPDX, from the repository
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From GitHub, fetched 19 Oct 2026.

Visit build123d.readthedocs.io ↗

build123d is a Python framework for parametric 2D and 3D CAD, an evolution of CadQuery ideas with a more Pythonic API. It produces precise B-rep models and exports STEP, STL and SVG.

Who it suits

  • Python users who want CAD as code: build123d is “designed for modern, maintainable CAD-as-code”, with models “suitable for 3D printing, CNC machining, laser cutting, and other manufacturing processes.”

From build123d.readthedocs.io, checked 19 Oct 2026. Quotes are the project's own words.

Fit: files and licence

Runs onPython
OpensSTEP, BREP, STL, DXF, SVG
SavesSTEP, STL, 3MF, DXF, SVG
Commercial useAllowed
Open-source licence (Apache-2.0): the Open Source Definition rules out restrictions on fields of use, including business use.

Sources: build123d.readthedocs.io/en/latest/import_export.html · opensource.org/osd, checked 19 Oct 2026. “Runs on” is from this listing. Blank means we haven't found it in official docs yet, not that it's unsupported.

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