The joke is that it's a zen garden, but if you're too busy to be mindful the robot will be mindful for you.

The guts are an old Ender 3d printer, I just took apart the X and Y axises and repackaged them in the base that I built. It runs a regular gcode file, just like it was printing something out. The files were on sandify.org which is a great online tool for making these kinds of 3d designs.