Three rounds of interviews: a phone screen with a recruiter, a phone interview with another QA and an onsite interview with managers, a dev, and another QA.
Overall, the interview was relatively easy. Everyone really went out of their way to make you feel as comfortable as possible. It was one of the friendliest, no-pressure interviews I've ever had.
Although (I thought) I provided the right answers, I was turned down. My guess is when I was asked a coding question by the dev, and I didn't provide the answer he was looking for.
The feedback I received was not specific either, but in looking at others' experience, this appears to be a common trend in Snap interviews.