1st interview was a quick phone call with a small screening process just to take some knowledge of the candidate, it was a quick and fun calm conversation. 2nd interview was a longer one with three more people in the call consisting of big pack of technical questions with some space to talk about it and some problems to solve (it was a 1h30/2h call). 3rd and 4th interviews were in the same day, one in the morning regarding team fit and rackspace fit, the 4th was a webex interview with an environment with some problems to solve.