8 interviews in total. 1 phone interview - basic programming questions to test my ability to program simple algorithms. Why do I like Python and Haskell, what's the difference between the languages. Asked me to expand on what static typing was vs. dynamic typing. Why would I use a hash map vs. a linked list? 3 on-site interviews in the London office - one algorithm design in Java, one general numbers and thought processes and one paired-programming type interview). 1 on-site interview with the head of the London office - general character questions, why I want to work for Palantir and similar styled questions. One brain-teaser which I couldn't immediately solved but worked through it with some prompting. 3 on-site interviews in the Palo-Alto offices, flown out over the weekend. Lunch and hotels provided! Palantir-themed system design question, followed by coding/data-structure question, followed by a data-structure/API-design question. One guy brought his dog into the interview - so cute! Was then sent home with promise of an interview with one of the cofounders. Overall very positive interview process! Lovely people and lovely offices.

I had behavioral interviews and then 4 in person interviews. The behavioral was straightforward. There was also a data query interview where they taught you a new "language" and had you execute basic queries in it. Then there was a system design interview. I had two of these. The last one they asked me if I was deployed to the moon to identify new species of alien what kind of system would I build.