TL:DR there were 2 interviews and a mechanical aptitude/tool test, whole process took about a month. I approached a recruiter at the career fair because I thought their presentation board with all the tools and gadgets looked cool. I sent a follow-up email to the recruiter the next day saying I enjoyed meeting. Two weeks later, I was contacted to do a phone interview. The phone interview was behavioral and pretty relaxed. The next week, I did a Microsoft Teams interview with two engineers, one of them being my manager. They wanted to hear a lot about my projects. The last step of the interview process was a 20 question test with some simple but deceptively tricky physics problems, and a 15 question tool-identification test. I got an offer about two weeks after that.

It was really easy, they wanted to know most about your experiences rather than what classes you're in. Which is good! Pretty big opportunity, so it is very competitive. The interview was very laid back.

I interviewed at the North St. Louis location. It started off with a few multiple choice timed tests that were supposed to measure your general intelligence in vocabulary, math, and things that engineers should know. It wasn't like statics problems, it was just like common sense questions.