Tell me about your experience working with backend systems. What architecture was used in the project, and how was the technical interaction implemented?

In my experience working with backend systems, projects were usually built using a microservices architecture. Each service was responsible for a specific business logic and interacted with others via REST API or gRPC. Message brokers such as Kafka or RabbitMQ were used for message exchange and event-driven communication.

Technical interaction was implemented through well-defined APIs using JSON or Protobuf for data serialization. Containerization (Docker) and orchestration (Kubernetes) were employed to ensure fault tolerance and scalability.

Within QA, I wrote automated tests to verify the correctness of interactions between services, as well as load tests to assess the overall system performance.