One half hour interview with campus recruiter which lead to an onsite interview in the following week. Offer was given the next business day. The interview consisted of 4 interviewers, each asking different questions. One was purely technical, about caching and data replication. The next few were mostly behavioral questions. I talked mostly about my class projects, what my role was in the team, and also why I was interested in the company. All the interviewers were very charismatic and had a lot to talk about regarding blackrock and their technology team.