In 2012, Momentum Machines created a prototype machine that allowed every part of a burger to be customized, from cook time, condiments, and thickness of patties, depending on the day’s menu.

A schematic of what the burger-bot looked like, released that year, showed a 24-square-foot Rube Goldberg-like machine, complete with a stamper that grinds and shapes custom blends of meat (like a one-third pork, two-thirds bison behemoth of a burger) and an oven.

“The burgers sold at 680 Folsom will be fresh-ground and grilled to order, served on toasted brioche, and accented by an infinitely personalizable variety of fresh produce, seasonings, and sauces,” according to the Craiglist ad.

The prototype could replace two to three full-time line cooks, saving a fast-food restaurant up to $90,000 a year in training, salaries, and overhead costs, tech blog Xconomy reported after catching a live demo.