FreeCAD

Official source code of FreeCAD, a free and opensource multiplatform 3D parametric modeler.

23 articles

How to Implement Custom Selection Filters in FreeCAD Using the SoFCSelection Gate

Learn how to implement custom selection filters in FreeCAD with the SoFCSelection gate. Discover how to control object selection and enhance your workflow effectively.

how-to-guide

Mar 28, 2026

Understanding FreeCAD's .FCStd File Format and Serialization System

Learn about FreeCAD's FCStd file format. Discover how FreeCAD uses ZIP archives and XML metadata with the App::ProjectFile class for efficient document serialization and storage.

internals

Mar 28, 2026

How to Use FreeCAD's PropertyExpressionEngine for Spreadsheet-Driven Models

Master FreeCAD's PropertyExpressionEngine to create spreadsheet-driven parametric models. Link properties to expressions for automatic updates when your source data changes.

how-to-guide

Mar 28, 2026

Understanding FreeCAD's ElementMap for Tracking Geometry Element Changes

Learn how FreeCAD's ElementMap tracks geometry element changes using kernel indices and user-defined names for persistent parametric modeling.

internals

Mar 28, 2026

How FreeCAD's DynamicProperty System Enables Runtime Property Addition

Discover how FreeCAD's DynamicProperty system enables runtime property addition for objects inheriting from App::PropertyContainer. Learn to create, modify, and remove properties dynamically during program execution.

internals

Mar 28, 2026

Creating Custom Parametric Features in FreeCAD's PartDesign Workbench Using Python

Learn to create custom parametric features in FreeCAD PartDesign using Python. Extend FreeCAD by building your own Python-based parametric objects.

how-to-guide

Mar 28, 2026

How FreeCAD Handles Document Recovery and Backup Using BackupPolicy

Learn how FreeCAD's BackupPolicy manages document recovery and backups. Discover automatic timestamped or numeric backups for safe, easy restoration and prevent data loss.

internals

Mar 28, 2026

Understanding FreeCAD's Undo/Redo Infrastructure with AutoTransaction

Explore FreeCAD's AutoTransaction class to automatically manage document transactions and ensure robust undo redo functionality within the FreeCAD codebase.

internals

Mar 28, 2026

How to Create Custom Draft Tools in FreeCAD Using GuiTrackers and GuiSnapper

Learn to create custom Draft tools in FreeCAD. Explore GuiTrackers for visual previews and GuiSnapper for geometric snapping to enhance your workflow. Get started today.

how-to-guide

Mar 28, 2026

FreeCAD Mesh-to-CAD Workflow: A Complete Guide to the Reverse Engineering Workbench

Master FreeCAD's mesh-to-CAD workflow. Convert mesh data to parametric CAD models using the Reverse Engineering workbench. Learn point cloud ingestion, surface reconstruction, and fitting techniques.

how-to-guide

Mar 28, 2026

How to Implement Custom Parametric Constraints in FreeCAD Sketcher: A Complete Developer Guide

Learn to implement custom parametric constraints in FreeCAD Sketcher. Drive constraint values dynamically using setConstraintExpression API for powerful, flexible modeling.

how-to-guide

Mar 28, 2026

Understanding FreeCAD's Coin3D Scene Graph and SoFCOffscreenRenderer: A Complete Guide

Master FreeCAD's Coin3D scene graph and SoFCOffscreenRenderer for leak-free off-screen image capture with Qt integration and metadata support. Learn how.

deep-dive

Mar 28, 2026

Have a question about this repo?

These articles cover the highlights, but your codebase questions are specific. Give your agent direct access to the source. Share this with your agent to get started:

Share the following with your agent to get started:

curl -s "https://instagit.com/install.md"

Add to your MCP client configuration:

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}

Ask your agent:

"Use Instagit MCP to understand how FreeCAD/FreeCAD works."

Works with

Claude Codex Cursor VS Code OpenClaw Any MCP Client

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