Plaid Software Engineer Interview Experience — Positive Feedback, Rejected for Background Mismatch

All the interviewers seemed pretty nice, but my impression was that they weren't that technically strong — didn't come across as too sharp.

Phone screen: a coupon question and a new question I don't remember too well.

They gave you a JSON mapping a bunch of routing numbers to bank names and had you process it — I forget exactly what the task was, but basically you just used various hashmaps to check things. The same bank could have different names. The follow-up was something like: what if you have multiple data sources? How do you handle conflicts? Like if three sources say a routing number belongs to BoA and one says Chase, how do you decide?

Onsite: design ChatGPT, plus the classic geo-distributed rate limiter question. The rate limiter also had a third part — given two different rate-limiting strategies (not FIFO order, but either always grab the biggest task or grab as many tasks as possible), you had to comment on the pros and cons of each.

Then I got a rejection saying the feedback was positive but my background didn't match... so why did you even bring me in for an interview?