2 min lesson
Technical phone screens & the AI-tools policy
Answer this as if it were happening now: "AI tools are allowed on Cursor's later technical screens. What is the safest assumption about the first technical screen and how should you use AI when it is allowed?" Say what supports your choice.
Step 1 of 2
Expect one to three roughly hour-long screens: live SQL and Python plus applied data problems, sometimes inside a real Cursor codebase. The distinctive twist is the AI-tool policy and getting it wrong can sink an otherwise strong screen.
Cursor allows AI tools - ChatGPT, search, Cursor itself - on its later screens, which is unusual and on-brand for the company. Multiple candidate accounts say the first technical screen is the exception: autocomplete only, no broad AI assistance. This varies, so confirm the policy per stage with your recruiter and assume the strictest version unless told otherwise.
When AI is allowed, the bar is judgment, not delegation. Use it for targeted syntax and lookup; handing the whole problem to a model reads as a weak signal and gets noticed.
Window functions for sessionization or running totals.
Deduplication and CDC: keep the latest record per key.
An incremental, idempotent transform that's safe to re-run.
Parse and normalize messy semi-structured event payloads.
Correctness on edge cases: late events, nulls, duplicates.
Trade-offs narrated aloud - correctness vs cost vs scale.
Idempotency and re-runnability, not just a passing query.
Disciplined AI use when it's allowed.
-- Latest row per entity from a CDC stream, safe to re-run
WITH ranked AS (
SELECT
*,
ROW_NUMBER() OVER (
PARTITION BY entity_id
ORDER BY event_ts DESC, ingest_seq DESC -- tiebreak avoids nondeterminism
) AS rn
FROM bronze.events
WHERE event_ts >= :watermark -- incremental, not full scan
)
SELECT * FROM ranked WHERE rn = 1;Narrate the cost and scale trade-off without being asked. Say “a full re-scan is correct but won't hold at billions of rows a day, so I'd watermark on event_ts and make the merge idempotent.” They evaluate reasoning over a query that merely passes and that one sentence shows platform thinking.