part001 = startSketchOn('XY')
  |> startProfileAt([0, 0], %)
  |> line(end = [0, 10], tag = $thing)
  |> line(end = [10, 0])
  |> line(end = [0, -10], tag = $thing2)
  |> close(%)
  |> extrude(length = 10)
  |> fillet(radius = 2, tags = [thing, thing2])