Question library
Questions from real interviews. Drill any of them by voice in a couple of minutes, with an interviewer, a score and feedback.
Your service calls another service over the network. What problems can come up, and how do you deal with them?JuniorA service saves an order to the database and then publishes an "order created" event to a message broker. What problems can come up here, and how do you solve them?Mid-levelYour service makes synchronous calls to an external service that sometimes responds very slowly or with errors. How do you keep that from taking your service down?Mid-levelCheckout involves three services, orders, payments and inventory, and each has its own database. How do you keep the data consistent if one of the steps fails?SeniorDesign a distributed rate limiter for a public API: limits are set per client key, and requests are handled by dozens of gateway instances.SeniorThe main table in your database has grown to several terabytes, and a single instance can no longer keep up with the writes. How would you design the move to sharding?Senior