Trader Intern

One phone interview followed by one onsite.

Phone interview was started with fit questions, with a few standard math / probability / expected value questions near the end. Very simple compared to ones from D.E. Shaw, Jane Street, etc.

Onsite was a two day process (Friday to Saturday), and included a good mix of technical questions (code test, St. Petersburg Paradox, etc.) and networking. Since they're such a small firm, I assume that the fit is much more important. Their technical screening isn't too rigorous - I saw several quantitatively brilliant people get filtered out because they didn't fit as well. I would be more concerned with coming across as personable than smart, once you pass a lower bound for the latter.