I applied online. The process took 4 weeks.
OA was some leetcode medium to hard stuff so be sharp on that. And then the first interview is some prob/stats qs which is standard for quant research applications in general. And then they ask some coding stuff which can be a lot of stuff. Then final round is a mix of stuff like C++, systems design, data science etc.
Some questions on prob and stats and leetcode
The following metrics were computed from 5 interview experiences for the Hudson River Trading Algorithm Developer role in London, United Kingdom.
Hudson River Trading's interview process for their Algorithm Developer roles in London, the United Kingdom is extremely selective, failing the vast majority of engineers.
Candidates reported having very good feelings for Hudson River Trading's Algorithm Developer interview process in London, United Kingdom.