got rejected after the Bloomberg final panel last fall. recruiter gave me the 'we went with someone whose experience more closely aligned' line. took me a few weeks to process it and i've been thinking about where i actually went wrong.
I interviewed for a data engineering role, infrastructure-heavy, C++ and Python environment. Here's my honest assessment of what I messed up.
1. I didn't prep for the systems-at-scale specifics. Bloomberg's data infrastructure handles enormous tick-by-tick market data at incredibly low latency. I answered system design questions in terms of typical web-app scale. I think that mismatch was visible. I should have studied the financial data infrastructure problem specifically: time-series databases, low-latency pub/sub, sequencing guarantees. I glossed over all of that.
2. Behavioral prep was too generic. I had fine STAR stories but they were generic tech stories. I didn't have a story specifically about working under deadline pressure in a production system that affected external clients. Bloomberg takes outages personally. Their brand is uptime and data accuracy. I should have had stories about exactly that kind of accountability.
3. I didn't ask the right questions. I asked "what does a typical day look like" and "how do you measure success for this role." boring. in retrospect i should have asked about the specific technical debt they were trying to address, what problems the team was hired to solve. that shows you actually care about the work, not just the job.
4. I didn't project the confidence they expect. Bloomberg interviewers push back. they'll say 'are you sure about that' and wait. i got flustered. you have to be willing to hold your position or revise it clearly, not just cave because someone raised an eyebrow.
hopefully this helps someone else. the rejection stung but i learned more from this process than i did from some loops i passed.