Sarah Simon contributed foundational kernel features to the hermit-os/kernel repository, focusing on UNIX domain sockets and file-system interactions. She established stub implementations for UNIX domain sockets, enabling the kernel to recognize the AF_UNIX address family and route requests while returning unimplemented errors to maintain build stability. Additionally, she scaffolded the fchdir system call, allowing dependent code to compile and reducing integration risk for future development. Working primarily in Rust, Sarah applied her expertise in kernel development, networking, and system programming to ensure repository build-ability and cross-module compatibility, laying essential groundwork for subsequent feature expansion and maintainable code evolution.