I applied online. The process took 4 days. I interviewed at FlexTrade Systems Inc. (London, England)
Interview
I applied online. The process took about 1 week.
Stage 1 was a 5-10 minute phone call with he HR manager. He asked about salary expectations, my knowledge, previous jobs, previous projects.
Stage 2 was the online codility test that took 90 minutes. There was one programming problem to solve using C++, If you are not familiar with different tree, graphs and other types algorithms it is difficult to pass the test. You need to write fast and optimized code, you can use your favourite editor and compiler but must compile under codility.
Interview questions [1]
Question 1
One of the codility problems about country network consisting of N cities and N − 1 roads connecting them.
I interviewed at FlexTrade Systems Inc. (Milwaukee, WI)
Interview
Exam was very difficult. The hackerank does not allow you to use any outside resources and I was unable to recall syntax for functional programming which was listed as a small requirement on the application.
I interviewed at FlexTrade Systems Inc. (London, England) in May 2026
Interview
First took me through an intro call, which was simple enough explaining my career from start to finish. I'm a junior dev, so I focused mainly on my one previously role, talked about arch, day to day and core language uses and application.
Recieved a private LeetCode link to complete within 7 days, was told 2 hours to complete but the LeetCode timer was set to 3 hours.
Passed 4/5 test cases, took 2h27 to submit the single question. Did a bit of digging after submitting - found this specific problem was not public. Really enjoyed the challenge, but my code must not have been flexible enough (that fifth test case failing caught me so bad and I couldn't get my head round it annoyingly - big fluster). Did not receive next round invite.
I applied online. The process took 2 weeks. I interviewed at FlexTrade Systems Inc. (London, England) in Nov 2025
Interview
Had a quick call with HR about the process, then sent a HackerRank (which could only be done in Java) easy(ish) lc. Then a half an hour behavioural interview with a senior engineer, before on-site which was 2 hours or so, another simple Java problem on the whiteboard, a simple math/data structure problem, and then general behavioural and team experience questions, from engineers on the team and then with the team lead. Rejected a couple days later, said other candidates were a better fit.
Interview questions [1]
Question 1
Do you like working in a small team? Have you ever done a project where you've owned the whole stack end-to-end? What's your process for debugging something? Tell me a time you had to manage conflict.