Обязанности:

Designed and implemented Kafka-based transaction processing flows, standardizing analytics and push notification events across multiple transaction types. Introduced unified debit/credit classification and migrated transaction analytics toward a common data model used by the analytics service.
Implemented Redis/Valkey-backed rate limiting and idempotency mechanisms for authentication and onboarding APIs, using distributed state to control repeated requests and protect sensitive backend flows.
Improved the reliability of external service integrations by introducing consistent error handling, localized responses, and Circuit Breaker mechanisms.
Moved frequently requested application resources from database-backed retrieval to Amazon S3-based delivery, reducing unnecessary database calls and improving resource access efficiency.
Implemented the backend WebAuthn/Passkey authentication flow shared by Android and iOS, including challenge management, credential registration, authentication verification, and server-side credential handling.
Supported services running in Docker and Kubernetes environments, investigating integration, configuration, messaging, and deployment-related issues.