# gumyr/build123d

A python CAD programming library

Repository: https://github.com/gumyr/build123d
Canonical: https://ross.abutalabs.com/products/build123d
Language: Python
License: Apache-2.0
License Family: permissive
Topics: 3d, brep, cad, cadquery, opencascade, python, 3d-models, 3d-printing, build123d
Last push: 2026-08-21T01:29:42+00:00

## Health v2 (maintenance only)
Score: 92/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 98, release rhythm 79, longevity 100
- inputs: {"age_days": 1520, "days_push": 13, "days_rel": 62, "gap_med": 69.5, "n_releases_24m": 7}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2926, forks 265 (observed 2026-08-28T04:07:30.371596+00:00)

## What it is
build123d is a Python-based parametric boundary representation (BREP) modeling framework for 2D and 3D CAD, built on the Open Cascade geometric kernel. It provides a clean, Pythonic interface for creating precise models suitable for 3D printing, CNC machining, and laser cutting.

## Use cases
- create parametric 3d models in python
- generate cad models programmatically for 3d printing
- design parts for cnc machining with code
- script 2d and 3d geometry for laser cutting
- build precise brep solid models without a gui cad tool
- automate repetitive mechanical part design

## When to choose
- you want cad-as-code with a fully Pythonic API
- you need precise BREP solids rather than mesh modeling
- you are migrating from CadQuery and want a more expressive algebraic API
- you need models exportable for 3d printing or manufacturing

## When to avoid
- you need a graphical interactive CAD environment
- you only need simple mesh editing or STL cleanup
- you work outside Python or need a browser-based CAD tool

## Facets
- artifact type: library
- maturity: active
- function: graphics, simulation, sdk
- domain: graphics, developer-tools, cross-platform
- platform: python, cross-platform
- tags: cad, brep, 3d-modeling, opencascade, 3d-printing, parametric-modeling, cadquery

## Member repositories
- gumyr/build123d (main) score 92

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:30.371596+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:33:36.748891+00:00, confidence not recorded.
  - readme: https://github.com/gumyr/build123d (fetched 2026-08-28T04:07:30.371596+00:00, sha 0da087842f8b)
  - registry_pypi: https://pypi.org/pypi/build123d/json (fetched 2026-08-29T09:48:50.747199+00:00, sha 2197b0a8d173)
- Data as of 2026-08-30T08:39:29.467469+00:00.