build123d

Pythonic code-CAD framework on the OpenCascade kernel

★ Stars3.5k3,458 on GitHub

Last commityesterday18 Oct 2026

LicenceApache-2.0SPDX, from the repository

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From GitHub, fetched 19 Oct 2026.

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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.

Free alternative to

Fusion 360

Details

Status	Open source
Licence	Apache-2.0
Platforms	Python
Category	Code CAD
Website	build123d.readthedocs.io
Source	GitHub

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