Chopper Trading Interview Questions
& Process

I got an email from a recruiter for an initial chat. Because I already had an offer, they were happy to speed things up and seemed eager to make it work. But, it took nearly 3 weeks to actually schedule the interview, which was supposed to be the final stage in the office after our quick talk. The date kept moving around for another couple of weeks. I flew in early that morning. They were really hesitant about covering flights or hotels, acting like they'd pay but then never actually doing it, so I covered all the costs myself. A trader joined me shortly after I arrived and asked some basic questions about my resume. It was a chill chat, but he wasn't very professional or prepared, unlike at other prop firms. He used a lot of profanity, which struck me as super unprofessional. Then he gave me 3 brain teasers. The first was easy, but the other two were tough – one was a number sequence based on the syllables of the numbers, totally irrelevant to the numbers themselves. He explicitly said he didn't care how I got the answers, just to give them to him. While I was trying to solve them, he just sat in the corner texting. I couldn't solve the last two, even though my approach was right, I just missed the specific answer. The other traders were busy, so I left not long after. They said the recruiter would call to set up more interviews, but it's been over a month, and I haven't heard anything, even after leaving multiple messages. They didn't even bother to reject me after a 15-minute interview with someone who clearly didn't care about the process, the fact I turned down a great offer to interview, or that I spent hundreds of dollars to fly out just to be sent home an hour later. If you have no other options, maybe consider them, but if this is how they treat candidates, I can't imagine how they treat employees.

Recruiter submitted my profile to Chopper after I applied through Dice. Chopper then had me complete a questionnaire about my experience with C++, Tools, Libraries, and development platforms. This was followed by a 30-minute technical phone screening with the team leader, where I was asked to explain how to implement a multi-threaded message queue using the boost thread library. Soon after, I was invited for an on-site interview. The on-site involved a two-hour, face-to-face session with the team lead and two engineers. During this, the team lead presented some simple C code on a whiteboard and asked me to identify potential issues like memory leaks, bad exceptions, uninitialized memory, and unexpected pointer deletion. One engineer focused on assessing my personality to see if I'd be a good fit for the team. The other engineer asked me to write a recursive function on the whiteboard to compute Fibonacci numbers with O(n^2) complexity, and then requested a linear time alternative.

A recruiter reached out to me, and I mentioned I was open to good opportunities even though I was happy with my current situation. My resume was submitted, and then I had to complete a self-evaluation regarding C++, Linux/Windows, Boost, etc. The first part of the phone interview involved typical programming questions like the difference between hashmap and binary tree, UDP vs. TCP, OOP, and polymorphism. The second part had two programming problems. For the first, I had to find character frequencies in a character stream, and I provided an O(NLogN) solution using a binary tree, which was accepted. Then, a variation with doubles (0.001 precision) was given, and I came up with an O(N) solution. For the second problem, merging K sorted collections of N elements each into one sorted collection, I initially proposed an O(KLogK*K*N) solution. The interviewer wasn't satisfied and hinted at more efficient sorting algorithms. I then developed an O(logK*K*N) approach where sorting happens only once initially, and then elements are picked and inserted. I explained my steps, but he cut me off, insisting sorting would be needed multiple times and dismissed my idea. I chose not to argue, deciding the role wasn't worth the effort, especially given his dismissive attitude.

The HR wasn't super organized and kept losing touch with the hiring manager. First, there was a phone interview where they asked why I wanted to get into trading. Then I traveled to campus for a face-to-face. They asked a riddle about timing 9 minutes using two 6-minute wicks, followed by a stats question. I didn't really like the vibe from the employees, and realized the job's demands (4pm-6am) weren't worth the pay for me.