Spoke to the team at a career fair and then was invited for a technical phone screen. The questions weren't too bad but still felt strange having the same questions as a front end developer when going for a firmware position.

Coding assessment, then a behavioral interview, a technical interview and finally a final virtual on-site that had 3 stages (2 technical interviews 1 behavioral). There was regular communication between each stage and a lot of flexibility with the timing. Overall a great process, though I was disappointed to not get an offer.