Pretty solid interview process. I felt the whole thing was very professional, despite a few small hiccups mostly around timing.
FIRST CONTACT: I applied through a referral in Nov 2017. A recruiter called me within a week, and we spoke on the phone about potential roles. Because of the holiday we had to set up the phone screen for mid-December.
PHONE SCREEN: There were two phone screens, one around machine learning and perception related domain knowledge and one focused more on coding. Both screens had some amount of coding, and I did both in C++. Coding questions were fairly standard ones, with a bit of a math bent to them.
ONSITE: I went onsite in Jan 2018. The visit was a half-day of interviews, starting at 1pm. I really appreciated that I didn't have to take a full day off work to attend this. Interviews were fairly split between domain expertise and coding. Reasonably challenging coding questions, I'd say around the same level of difficulty as a Google or Facebook coding interview. I got to check out the cars and got a hand written thank you card for coming in, which was nice and I really felt like the interview was a two-way process.
OFFER: I received an offer a week or so later. Comp was competitive with competing offers from Facebook and Google, although not before negotiation.
NEGATIVES: Not much. One interviewer forgot about me and came late, so we had to shorten that interview by 10ish minutes, so that wasn't great.