Voleon Software Engineer Interview Experience — Passed Every Round, Rejected With Zero Feedback

This was the company I spent the most time preparing for, and it was also the one that went the smoothest. The recruiter kept telling me things looked fine, and in the end I solved every single technical question — and they still rejected me. Feels like a complete waste of time. I went through the entire process, and when the rejection came they didn't give even a bit of high-level feedback. Zero respect.

• Phone screen: kac ring
• VO1: '0' is a good string, and '1<good str><good str>' is also a good string, e.g. '100', '11000', '1100100'. The question was to check whether a given string is a good string. Should be solvable in O(n).
• VO2: A really long OOD (object-oriented design) coding question, similar to an earlier stock-trading question I'd seen but not the same one — too long to write out in full here.
  • Question 1: Focuses on handling and processing market data streams efficiently using concepts like queues and dictionaries to simulate a broker's interaction with a stock exchange.
  • Question 2: Tests the ability to design and implement logic for trading on behalf of a single client, considering constraints like participation rate and market conditions.
  • Question 3: Builds on Question 2 by introducing multiple clients, requiring candidates to handle cascading effects and prioritize trades while maintaining fairness.
• VO3: Sparse matrix, add/multiply. Worth noting: pay attention to error handling, especially when the dimensions don't match.
• VO4: Points and queens. The question asks how many times each point can be hit; part 2 adds rocks that can block the queen's line of attack, solved with binary search.

Thinking back on it afterward, I think I probably got cut in the round with a really mean interviewer — the coding part went fine, then it suddenly switched into a systems design question, and the interviewer just kept pacing around the room the whole time. Felt really disrespectful.