I was referred by an internet friend who worked at Mirantis. We talked, he told me what the company is doing, and it seemed great. I had 2 interviews: 1 with an engineer and with my future manager, and 1 with the company's director of engineering. Both interviews had interesting algorithmic problems, took about an hour and generally went well. I was hired exactly for what I was expecting, and it was a fascinating project that's all I could ever dream of.