Describe a complex task from your recent experience: what was the difficulty and how was it solved?

In one of my recent projects, I worked on a real-time big data processing system, where the key challenge was ensuring high performance and scalability while processing multiple parallel requests simultaneously.

The problem was that standard approaches using synchronous calls and locks led to bottlenecks and delays. To solve this, I implemented an architecture based on reactive programming using Project Reactor and WebFlux, which allowed asynchronous and non-blocking request processing.

Additionally, I optimized database interactions by implementing caching and batch processing of requests to reduce load. As a result, we achieved a significant increase in throughput and a reduction in system response time.