I first contacted Logos by e-mail. I also asked a friend who knew a Logos insider to e-mail a recommendation. After a long wait, Logos contacted me for a phone interview, which consisted mainly of technical questions to test my knowledge of programming languages, algorithms, and data structures. Apparently it went well, since they offered to fly me to Bellingham for an onsite interview.
I read and watched everything on the Logos website about the company's culture and products, including the founder's ominously titled book "Fire Someone Today". Anyone interested in working here should do this!
The on-site interview included a panel interview followed by lunch with several developers and a one-on-one with the CEO/founder. I get the feeling the one-on-one would have been canceled if the group interview didn't go well. For the panel interview I was asked to solve several technical problems on a whiteboard, and asked a wide range of questions about my experience and how I would solve various technical problems. There were no weird psychological questions. In the final interview I asked several questions about the company's culture, ownership structure, and future plans. I liked the answers.