The entire process was smooth and quick. I sent my resume from a recruiter that I met on campus and told her I was interested in a part-time software engineering internship during the school year, explained my interests and background, and she set up a call for us. Her and I talked, got a feel for what I was looking for, and then started me on the interview process.
The first interview as a phone technical interview. They sent me a link to a code-sharing site and had me talk with one of their engineers to prove basic competence. There were a couple flimsy interview-style questions (Tell me about a time when there was a problem you couldn't solve), and then an coding challenge. I used python, which I was rusty with, but my interviewer did a good job at focusing on my problem solving process and not my syntax.
The same day I got a call inviting me to come do an on-site interview a few days later. I'm local, so I was able to drive to their campus and do the interview. It was one simple interview with another engineer. We talked, got to know each other, he asked me why I chose CS, etc. He was very personable and the atmosphere felt very relaxed and low-pressure. He had a couple of coding challenges for me which I did on his laptop in Sublime. Neither were especially difficult - standard interview coding questions, first focusing on the solution and then optimization.
After the interview I was given a tour of the building, which is quite impressive. Everything was pimped out, kitchens everywhere, a band area where you can play electric instruments with headphones, sitting areas, props of every kind, foosball tables, a gym, etc. etc.
Later, I believe the same day, I was called again by my recruiter and invited to do one more phone interview, this time with a higher-up engineer, who I believe was over three or four teams. This was also fairly relaxed feeling. He asked me a lot of questions about my current internship. He asked me to explain very specific things about our process and specific problems I've had to see how well I understood them. That was most of the interview. The very end was a basic Javascript coding challenge (I had JS on my resume, and Qualtrics uses a lot of it) asking me to walk through some code he'd written and explain what was going on. The questions were very oriented around closures, first-class functions, and the ways that they could be used in JS. Again, he focused not on my syntax, but on my process and ability to think through the problem and understand the concepts. I thought he was a very skilled interviewer, and I can see how his interviewing methods could be much more effective than traditional technical interviews with just coding problems.
The last interview was a Monday, and I received an email and subsequent phone call with an offer the following Friday. I was impressed with the smoothness and seamlessness they demonstrated throughout.