Don't even worry about Dyret the robot. At first glance, the scrawny quadruped looks pathetic, as it struggles to walk without collapsing. But keep watching, and you’ll see it start to improve—walking slowly, yet ever more proficiently. Dyret the robot is teaching itself to walk. Or even, according to a new class of robotics researchers, evolving. Machines like Cassie the biped or SpotMini the robot dog are quickly mastering locomotion, thanks to line after line of meticulous code.