Phone interview with the manager and another engineer followed by an in-person interview a week later. Phone interview lasted 45 minutes. The in-person interview lasted five hours and was with five different people, one after the other. The final part included a lab exercise. After the interview I sent a thank you note to each person I spoke with. I followed up a week and two weeks after the interviews. After two months of no response I sent a message to the hiring manager who finally acknowledged they filled the position.