Onsite interview: A few nice people but still a bad experience.

Four rounds:

1. ML design round: Given a group chat log, build a model that can extract all the different conversation threads going on.
2. Coding round: Build a streaming API that returns the current top-k companies based on the number of times they were mentioned in news stories.
3. ML design round: Build some model that can predict word breaks (e.g., "whyamihere" -> "why am i here"). Code up k-means algorithm.
4. Manager round: I honestly can't remember.

Impressions

1. This round went very well—interviewer and I got along and they gave me a few helpful hints when necessary.
2. Coding round was a hot mess. Interviewer was non-cooperative and would criticize almost every answer I gave. At one point, I said the complexity was O(n) and he said "well, technically it's O(n + log(n))". I would hate to have this guy as a coworker.
3. Went alright. I noticed that the interviewers enjoy asking for equations at every opportunity. This was the third round (including phone rounds) with Bloomberg where I was asked to write the cross-entropy equation.
4. No comment.

Definitely rejected due to round 2. When an interviewer dislikes you, I found it much harder to perform well. I began to doubt myself and was sick of listening to the guy lecture at me. I probably also didn't appear enthusiastic about their products enough.

They took over a week to send me an automated rejection email, which only happened because I asked for an update. Overall, the interviewers' attitudes and recruiters left a sour taste in my mouth.