The OA consists of 3 hours 40 math questions including probability, brain teasers, linear algebra, statistcs, algorithms, geometries. no break, not very hard, but not easy at all. The most difficult problems are the geometric ones.
First step was a coding test comprising of probability and some basic coding questions. They are doable if you have practiced beforehand. Then subsequently are rounds of technical interviews with various quant researchers. They ask your experience and also test some standard quant interview questions such as probability or machine learning questions.
Interview questions [1]
Question 1
Standard probability questions that can be found in quant interview textbooks.
interviewed with WQ, first round was series of questions on ML basics: linear regression.. second round more focused on coding and more ML. The interviewers were friendly and they gave me hints towards solutions