How do you handle rate limits when calling a customer's API?

Summary

Throttle client-side below the limit, read rate-limit headers, on 429 or 503 honour Retry-After or back off exponentially with jitter, cap retries and alert, and checkpoint progress. Agree large backfills with the API owner and prefer bulk exports for history.

Longer Answer

Instant retries from many workers look like an attack and can get the integration locked out, harming the customer's own users who share the quota.

Key Points

• Client-side throttling.
• Retry-After and jittered backoff.
• Cap retries; checkpoint.
• Coordinate backfills.

Deep dive: Forward Deployed Engineering in Practice: The Backfill That Got Us Blocked

What interviewers look for

Respect for shared infrastructure and correct retry behaviour.