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Backend · Junior · Theory

Your service calls another service over the network. What problems can come up, and how do you deal with them?

~4 min by voice

How to approach it

This checks whether the candidate understands that the network is unreliable and slow, and knows the basic defenses: timeouts, retries with backoff, idempotency, a circuit breaker, a fallback and monitoring. The key subtlety is that on a timeout you don't know whether the operation went through.

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Best with headphones · ~4 min