Sam Che delivered a targeted performance optimization to the JetBrainsRuntime repository, focusing on AArch64 AtomicLong methods. By conditionally omitting a redundant memory barrier when the Large System Extension (LSE) is not present, Sam reduced unnecessary synchronization overhead and instruction count for non-LSE configurations. This change, implemented in C++ with a strong emphasis on assembly optimization and low-level programming, improved throughput for concurrent AtomicLong workloads. The work demonstrated a precise understanding of both hardware architecture and compiler development, resulting in a minimal yet effective code change that addressed a specific performance bottleneck in high-concurrency environments without introducing new bugs.