Comment by WillAdams

Opensource options include:

- Solvespace --- limited to 2D last I checked

- FreeCAD has a workbench for CAM/toolpath generation

- BlenderCAM is a plug-in for Blender which is well-regarded, and together w/ CADsketcher/BlenderCAD works well for some folks

- Kiri:Moto

- pyCAM --- a venerable option, it worked well ages ago when I used my son's gaming computer to make toolpaths.

Rather rough (possibly outdated) list at: https://old.reddit.com/r/shapeoko/wiki/cam