Over the summer, two software engineers at Mixus, a San Francisco–based artificial intelligence startup, staged a bit of a rebellion by refusing to follow instructions to rely heavily on Cursor or any of the other popular new coding-assistance software.

They figured "they could do better than Cursor," said an incredulous Shai Magzimof, Mixus' co-founder.

With just five full-time employees, the duo's revolt was a substantial headache for Magzimof. One of the anti-Cursor engineers said he used it to auto-complete individual lines of code, but that still wasn't the type of heavy use Mixus wanted. "Are you joking?" Magzimof recalled asking the engineer.