just finished robinhood's OA last week so this is fresh. sharing because i couldn't find good recent info when i was prepping.
the online assessment is on codesignal, two problems, 70 minutes total. both were medium difficulty by leetcode standards. the first was a graph/BFS variant, the second was a sliding window string problem. nothing that would be labeled 'hard' on a good day, but you need to be clean and fast because the timer is real.
a few things that stood out:
time pressure is the actual test. 70 minutes for two mediums sounds fine until you realize codesignal runs its own clock and the environment is a little janky. i spent 8 minutes just figuring out how to test locally within their editor.
clean code matters. i've heard from someone inside that they look at code quality, not just correctness. write real variable names, add a comment or two. don't just dump a solution that passes test cases.
topics i've seen mentioned across multiple reports: arrays, hashmaps, graphs (BFS/DFS), dynamic programming, sliding window. trees occasionally. system design does NOT appear at the OA stage.
my background: backend swe, 4 YOE, applying for a mid-level role. passed the OA, now waiting to hear about the phone screen. will update if i get further.
one tip: robinhood is a fintech company, so fintech-adjacent problems (running totals, portfolio calculations, transaction streams) have shown up in a few people's reports. worth thinking about data structures for streaming numeric data.
if you're a new grad: the difficulty is the same but the bar for what they consider 'passing' may be different. i've seen new grad reports where both problems had to be fully solved to advance.