I recieved a phone call by one of the two people that would later interview me. She asked me 15ish technical questions and skipped a bunch of the others. The very next day they wanted an in person interview. I met my contact and she took me in a room and threw some light questions at me and then a man "burst" through the door and immediately started asking more technical questions and really drilling in. It seemed like a good cop bad cop kinda ploy and very unproffessional. It was almost like they were bored with interviewing and wanted to mix it up. The only reason I put the interview was difficult is I wanted to tell them how stupid they were being but had to hold my tongue.