I’ve been developing a FreeCAD macro for a while with the following aims:

• Get to grips with FreeCAD and parametric modelling concepts: sketches, constraints, datum planes etc.
• Learn Python and use it for FreeCAD scripting

To really push the boundaries, I challenged myself to use Python scripting in conjunction with the PartDesign workbench: I wanted to end up with a parametric model fully based on sketches and datum planes.