Lixin Yang contributed to the NixOS/nixpkgs and nix-community/home-manager repositories by delivering targeted improvements in system configuration and security. Over two months, Lixin upgraded the oidc-agent package for compatibility with WebKitGTK 4.1 and enhanced the HDRMerge build system by refining ALGLIB integration, which improved build reliability and reproducibility across environments. In home-manager, Lixin implemented a security-focused feature that restricts the SSH agent to a whitelist of PKCS#11 libraries, reducing potential attack surfaces. These changes, developed using Nix and leveraging expertise in build system configuration and package management, addressed both maintainability and security in cross-platform NixOS deployments.