CAD-N is licensed under the MIT License (see LICENSE). It depends on,
and its packaged builds redistribute, the third-party open-source components listed
below. Each retains its own license; full texts are in the LICENSES/
folder where noted.
| Component | Version | License | Full text |
|---|---|---|---|
| ezdxf | 1.4.4 | MIT | LICENSES/ezdxf-LICENSE.txt |
| NumPy | 2.4.6 | BSD-3-Clause | LICENSES/numpy-LICENSE.txt |
| Shapely | 2.1.2 | BSD-3-Clause | LICENSES/shapely-LICENSE.txt |
| GEOS (bundled inside the Shapely wheel) | — | LGPL-2.1 | LICENSES/GEOS-LICENSE-LGPLv2.1.txt |
| PySide6 / Qt | 6.11.1 | LGPL-3.0 | see "LGPL components" below |
| shiboken6 | 6.11.1 | LGPL-3.0 | see "LGPL components" below |
Copyright holders (permissive components):
- ezdxf — Copyright (c) 2020 Manfred Moitzi (MIT)
- NumPy — Copyright (c) 2005-2025, NumPy Developers (BSD-3-Clause)
- Shapely — Copyright (c) 2007, Sean C. Gillies; 2019, Casper van der Wel; 2007-2022, Shapely Contributors (BSD-3-Clause)
CAD-N uses PySide6 (Qt) and, via Shapely, the GEOS geometry engine. Both are licensed under the GNU Lesser General Public License and are used as dynamically linked shared libraries — CAD-N's own MIT-licensed source is not a derivative work of them.
In packaged builds these libraries ship as separate, replaceable shared libraries
(*.dll). In keeping with the LGPL you may obtain the corresponding library source
and substitute your own compatible build of either library:
- Qt / PySide6 — LGPL-3.0. Source and license: https://www.qt.io/licensing and
https://download.qt.io/. The full GNU LGPL-3.0 text: https://www.gnu.org/licenses/lgpl-3.0.html
To replace it, install your own copy of PySide6/Qt (
pip install PySide6) or swap the bundled Qt DLLs in the application folder. - GEOS — LGPL-2.1. Source: https://github.com/libgeos/geos. The bundle notice and
license text are in
LICENSES/GEOS-LICENSE-LGPLv2.1.txt. To replace it, install your own Shapely/GEOS build or swap the bundledgeos*.dll.
See NOTICE for the short-form LGPL statement that accompanies binary releases.
These are used only to develop, test, or package CAD-N and are not included in the shipped application, so their licenses impose no obligation on end users:
| Tool | License | Note |
|---|---|---|
| PyInstaller | GPL-2.0 with bootloader exception | The exception explicitly leaves apps it builds unencumbered. |
| pytest | MIT | test runner |
| matplotlib | PSF/BSD-compatible | dev visualization only (excluded from the build) |
| Pillow | MIT-CMU | icon generation only (excluded from the build) |
Regenerate this inventory after a dependency bump by re-copying the texts in
LICENSES/ from the active virtualenv's *.dist-info/licenses/ folders.