What professional moments or tasks in recent years have been the most difficult or caused the greatest challenges for you?

The most challenging professional moments are often tasks related to debugging complex bugs, especially when the problem manifests irregularly or depends on multiple factors. For example, in Java projects, this could be a memory leak due to improper resource management or complex concurrency issues such as data races and deadlocks. Solving such problems requires a deep understanding of the language, profiling tools, and a systematic approach to analyzing code and logs.