Plaid · Primly Community

Survived the Plaid onsite: here's what actually came up

backend_bekah · 4 replies

Went through the full loop last month for a mid-level backend role. Sharing because I couldn't find a lot of recent info when I was prepping.

Phone screen was a pretty standard medium-difficulty DSA problem. Nothing wild. The recruiter told me ahead of time which topics to expect which was... surprisingly helpful.

Onsite was four rounds back to back over Zoom:

Coding round 1 - string manipulation + a small graph problem. Medium difficulty. I finished with time to spare but they kept pushing on edge cases, which felt deliberate. Don't just get to the answer, think out loud about what breaks it.

Coding round 2 - more applied. Something about parsing financial transactions. Felt very on-brand. They asked me to handle duplicate entries, which matters a lot in their domain obviously.

System design - design a bank account aggregation service. I mean, yeah. If you haven't thought about idempotency, retry logic, and what happens when a bank API returns garbage data, study that. They nodded when I brought up exponential backoff. They wanted to know my failure modes before my happy paths.

Behavioral - pretty standard, ownership and conflict. My "disagreed with a decision" story landed well.

Total process from application to offer was about 5 weeks. Timeline felt reasonable. The interviewers were engaged, not just going through motions. Ended up declining for comp reasons but good experience overall.

4 replies

infra_ines

the bank API returning garbage data angle is so real. half of plaid's actual engineering problem is just... banks are bad at APIs. makes sense they'd probe for that in the design round.

backend_bekah

exactly. i said something like 'assume 15% of responses from external banking APIs will be malformed or timeout' and the interviewer literally said 'that's generous.' so yeah, go even more pessimistic.

remote_swe_42

you declined for comp reasons, can you say more? were they not moveable or was the initial offer just that far off?

backend_bekah

initial offer was competitive but not SF-market. i was coming from a public co so the equity math didn't work for me personally. they did negotiate, to be fair. just wasn't enough of a delta.