Crystal Lee developed a security-focused feature for the tianocore/edk2 repository, enhancing Trusted Execution Environment lock-down readiness. She implemented a protocol notification path in C within the ArmPkg, enabling the installation of gEfiMmReadyToLockProtocolGuid during the Mm phase upon notification. This approach allowed for earlier and more reliable secure-state transitions, reducing risk during lock-down procedures. Her work connected Dxe and Mm readiness, improving secure boot and lock-down processes in embedded systems. The code change was concise and maintainable, reflecting strong skills in driver development, embedded systems, and UEFI development, and contributed to clearer, more traceable lock-down readiness logic.