A really bad experience. First they send a HackerRank test without even knowing what the position is or what they are looking for. The test was ok, but not related to embedded systems at all.
I had an interview with the technical manager of the area. His manners were rough and always mentioning that he didn't had time. He ask me to complete another coding test in C in that moment, using an online compiler. I did it, but the compiler stopped working, and I finalize it using my own compiler. During the test he said things that made clear that he didn't have an idea of the test itself or a possible solution, anyway he tried to help.
After that I asked about the job in the company and he said in bad manner that they never ever change a deadline and they have to work on weekends if necessary to achieve. I was shock by the way he mentioned this and without related context, not something to say this way in the first interview.
They did not communicate with me anymore after that interview. For what I heard from this guy I'm certain that it is not a nice place to work.