Office and culture is definitely the "Dev" culture. Relaxed, Techy and good break out areas.
I had a telephone interview of an hour then 3x1 hour interviews on one day and then called back for a further interview.
First of the group of three was technical, followed by team fit then lastly a technical overview. Be sure you know as much as you should for the role.
HR was pleasant, and open to talking about salary and your interview experience to gage your interest, situation and possibly body language to see if your the right fit.