Tell about a technically challenging task.

One of the technically challenging tasks was related to optimizing the performance of a distributed data processing system. It was necessary to reduce delays when aggregating large volumes of information from multiple sources in real time.

The problem was that data arrived at different speeds and formats, and also had a high update frequency. It was essential to ensure consistency and minimize response time.

The solution included:

• Implementing asynchronous processing using CompletableFuture and reactive streams
• Using caching of intermediate results with TTL
• Applying the Circuit Breaker pattern for resilience against external service failures
• Optimizing data serialization and reducing the volume of transmitted information

As a result, delays were reduced by 40%, and the system's reliability was increased. This experience demonstrated the importance of a comprehensive approach and a deep understanding of architecture.