SZY Electronics PCB Coasters

So I had no idea how to tell KiCAD where to keep soldermask off so I could have all the traces exposed.

When I realized, duh, you just draw on the soldermask layer. Since the boards are already 100% covered in mask, obviously when you draw on the soldermask layer it'll remove soldermask where you draw.

So now the board has exposed traces as artwork!