DevOps

Tell me about the implementation of graceful shutdown and proper operation handling.

Tell me about the development of the feature toggle mechanism.

How was idempotency implemented — on surrogate keys or business indicators?

Tell us about API design and interaction contracts: approaches, standards, protocols, schema stores.

Have you used DLQ/DLT topics? How were retries organized — synchronously or asynchronously?

Have you had problems storing a large volume of idempotency keys?

Did you encounter issues with event order during asynchronous retries?

How was idempotency ensured during retry requests to payment gateways?

Tell about PostgreSQL optimization: indexes, batch operations, transactions, reducing locks.

Tell me about the MVCC concept in PostgreSQL: how it works, bloat, vacuum, and its relation to transaction isolation levels.

What do you pay attention to during code review?

What are your expectations from the new company and project?

Have you ever applied isolation levels higher than read committed?

Tell me about developing platform libraries and templates for services at Gazprombank.

Tell about sharding a database to reduce load.

Is it normal to make a synchronous call to an external service inside a transaction?

Tell about a project at Megafon: architecture, technical details, stack.

Tell us about the export and secure storage service for reporting, access control.

Tell about a universal adapter for external payment gateways: architecture, retry, fallback, circuit breaker, configurable mappings.

Tell about developing batch processors for mass operations: approaches, problems, solutions.