I applied online. After few days someone from HR in California office contacted me, she asked few questions and proposed to schedule technical interview with one of their engineers. Technical interview was scheduled quickly and I had 1 hour phone interview with one of their engineers. He mostly spoke himself about their project, how stuff works etc. After 30 minutes of telling about project and company I was asked few questions about my experience and my resume. Interviewer mentioned that they are using Go as programming language not C/C++ or Python as on my resume and that it is easy to learn. Day after the technical interview same HR person called, she said that my technical interview went well but this time she quickly became very rude and pushy asking how I found out about company and if I know anyone who already works there etc. I answered all her questions. She was clearly unhappy about something not sure what. Day later I got email telling me that they have reconsidered.