Casual, as I knew the Principal Investigator. We spoke once about the position, and I accepted the offer. I learned more about the position and the opportunity arose when the PI's funding came through, albeit a little bit into the fall semester. I met the primary administrator and other staff during the process. All were welcoming individuals who gave me the opportunity to ask questions.

Pretty casual and straightforward. Welcoming faculties and staffs. The interview is more like a confirmation once the decision is made by the hiring personnel. Just providing a data point here.