Received a phone call shortly after applying to schedule a phone interview in about a week. Short phone interview queried by knowledge of the company and why I wanted to work there. Was asked about my programming experience and whether I was geographically flexible. At the end of the phone interview I was told I made it to the next stage (in-person all-day assessment) which was scheduled the week after.
The assessment started with us introducing ourselves to the group and answering "If we could interview one famous person, who would it be and why?" Almost everyone gave the obvious generic answers (Bill Gates, Elon Musk, etc.) which seemed to be received well by those asking.
In total there were three tests and two interviews. The tests covered very elementary mathematics (they give you a booklet in advance that tells you the covered material), basic language-agnostic programming problems. If you have a STEM degree you'll probably find them insultingly easy.
One interview was behavioral, the other technical. The technical asked the standard object oriented (difference between interface and abstract class, overload vs override, primitive vs reference type, == vs .Equals, what is encapsulation, etc.) and database (what is a primary key, what are the joins, etc.) questions. The behavioral asked about your knowledge of the financial industry and motivation to work there, your background, why you want to work for FDM.