In March 2026, Tom Sheinen focused on stabilizing ARM tail-call handling within the Go toolchain repository. He addressed a critical bug affecting stack depth management for arm32 tailcalls, implementing precise stack pointer adjustments to ensure safe function returns and prevent stack miscalculations that could cause crashes or undefined behavior on ARM builds. His work involved deep understanding of ARM architecture, compiler design, and system programming, and was validated through code review and automated LUCI tests. By refining the tail-call code path in Go, Tom improved runtime reliability for ARM targets, demonstrating careful attention to low-level systems correctness and maintainability.