But what if your toilet weren’t a toilet at all? What if you could simply feed your waste to mushrooms that would purify it into soil, naturally?

This gleaming machine turns human poop into fertile soil

That’s the vision of Rebecca Schedler. As a graduate student at Design Academy Eindhoven in the Netherlands, Schedler built the Symbiopunk, a bioreactor that transforms feces into humus—the fertile, black substance in soil (not the chickpea dip). The work was done in collaboration with the composting toilet company Kildwick.

The Symbiopunk is entirely mechanical, requiring no electricity to operate. You feed solid waste into the Symbiopunk’s large copper drum. (It flips upside down, and spins left to right, to make this job easy.) The waste sits in this copper for two to three days, because over this time feces will actually increase in temperature due to its active microbes. The copper offers a literal cooling-off period, and copper itself is antimicrobial, which helps sterilize the waste.