This field changes monthly. Tell me about a time something you had built became outdated fast, and how you handled it.

Question

Accepted Answer

I spent about three weeks building a careful few-shot pipeline for extracting line items from supplier invoices, prompt engineering, format coaxing, retry logic for malformed JSON, and roughly two months later the provider shipped native structured outputs plus much better document understanding in the same price tier, which made maybe 70 percent of my careful work unnecessary. The useful part is how we decided to migrate, because most announcements do not deserve a migration. My filter is two questions: does it change our cost or quality on our eval, and does it delete code we maintain. I re-ran our invoice eval suite, 200 labelled documents, against the new capability in an afternoon: accuracy went from 91 to 94 percent, and the retry-and-repair code, about 400 lines that accounted for a disproportionate share of our incidents, could go entirely. That cleared both bars, so we migrated, behind a flag, old path as fallback for two weeks, then deleted. What I took from it shaped how I work. First, the eval suite is what made the decision cheap: without it, "should we adopt this" is a week of debate, with it, it is an afternoon of measurement, so the suite is the asset that converts churn from a threat into free upgrades. Second, I stopped building elaborate workarounds for model limitations without asking whether the limitation is likely to be short-lived, some workarounds are load-bearing product code, others are scaffolding around a gap the next release fills, and I now label them accordingly, scaffolding gets built cheap and expected to be deleted. My standing filter: anything that claims to move our tasks gets an afternoon against the eval suite; leaderboard wins on tasks we do not run get ignored; and one afternoon a month is budgeted for trying things with no immediate justification, which is where two of our later wins came from.

Answer

How do you avoid your team churning on every model release?

The gateway plus eval-gate pattern: releases are evaluated against the suite on a schedule, adopted by config flip when they clear a threshold, ignored otherwise. Process absorbs the churn so people do not have to.

Answer

What in your current skill set do you expect to be obsolete in 2 years?

Honest answers name specifics, prompt-format tricks, manual context management, and identify the durable layer: evals, data quality, system design, and knowing what good output looks like in a domain.

This field changes monthly. Tell me about a time something you had built became outdated fast, and how you handled it.

This field changes monthly. Tell me about a time something you had built became outdated fast, and how you handled it.

The follow-ups they ask next

What the interviewer is listening for

What sinks the answer

If you genuinely do not know

Keep going with behavioural

Knowing the answer is not the same as recalling it under pressure