{
  "version": "0.1",
  "nodes": {
    "1": { "id": 1, "name": "BaseCube", "op": { "type": "Cube", "size": { "x": 50, "y": 30, "z": 20 } } },
    "2": { "id": 2, "name": "BaseBlockPositioned", "op": { "type": "Translate", "child": 1, "offset": { "x": -25, "y": -15, "z": 0 } } },
    "3": { "id": 3, "name": "CutCube", "op": { "type": "Cube", "size": { "x": 25, "y": 30, "z": 10 } } },
    "4": { "id": 4, "name": "CutPositioned", "op": { "type": "Translate", "child": 3, "offset": { "x": 0, "y": -15, "z": 10 } } },
    "5": { "id": 5, "name": "SteppedBlock", "op": { "type": "Difference", "left": 2, "right": 4 } }
  },
  "materials": {},
  "part_materials": {},
  "roots": [{ "root": 5, "material": "default" }]
}