The interview process consisted of 3 phone screens (2 with the recruiter, 1 with the hiring manager), followed by 4 technical rounds covering different topics such as automotive communications, HIL system design, a Python coding challenge, and behavioral questions. This was then followed by an additional follow-up call with the coding interviewer and hiring manager bringing it to 6+ rounds total! All technical rounds went well from my side. The coding challenge was explicitly framed as "logic matters more than working code." The follow-up was described as "nothing make or break", it involved explaining my solution and answering 3 additional technical questions, all of which I addressed confidently. Shortly after, a rejection with zero explanation or feedback. What makes this particularly frustrating is that I'm a former GM employee with directly relevant HIL experience. Putting a candidate through 6+ rounds, framing the final round as low-stakes, and then rejecting them without any substantive feedback is disrespectful of everyone's time. Its a HIL simulation position focused on Simulink and other simulation tools like CarSim, dSPACE ASM, VTD, etc., the fact that a coding challenge was even part of the process was a little too much, and the fact that they based their decision off that (my guess) seemed really detached from the rest of the interview rounds, which again went really well. The recruiter was pleasant and communicative throughout, which I appreciated and also gave some good pointers for the technical rounds. But the overall process felt like poor alignment between the interview team and the hiring decision. Advice to GM: If you're going to run a 6-round process especially with a former employee, candidates deserve real feedback when it doesn't work out. A form rejection after that investment isn't good enough.