The process was long for me but not too bad. I had 2 phone interviews and then a coding challenge which was 4 somewhat basic c questions on hacker rank.

The interviewer asked about my experiences and gave a short overview of the company's history and how they operate. He also asked what my greatest strengths and weaknesses that are relevant to the company were. I was also asked to look at two devices, one a circuit board, and the other a device contained in a white case. When I gave a fairly accurate description, he confirmed my description, and described what the device is/does. The interview ended with questions that I had about the company. The interviewer himself was very difficult to read, keeping a straight face. I couldn't tell if this was because he was just keep a straight face, or if he was simply disinterested.