In January 2025, Alessandro Lacchini focused on backend reliability within the istio/istio repository, addressing a concurrency issue in the JWKS resolver cache. He resolved a TOCTOU race condition by implementing a compare-and-swap mechanism in Go, ensuring atomic cache updates during JWT public key retrieval. This change improved authentication stability, particularly under high load and during key rollover events. Alessandro applied concurrency handling and rigorous testing to strengthen the cache’s safety, reducing intermittent validation failures. His work demonstrated a deep understanding of backend systems and concurrency patterns, contributing to the overall resilience and security of Istio’s authentication infrastructure.