Dynamic box beveling

I think my initial approach should be fine. So I only have to scale down the shape to build my box. So I can generate all the vertices for my box but I am not sure how to fill the spaces.

https://www.babylonjs-playground.com/#GW2F0U#17

Do you have an idea how to do that? Maybe with extrudeShape? I don’t get how to scale along the path. It just scales the complete mesh but that’s not successively like with rotation: https://playground.babylonjs.com/#MR8LEL#75