11.10.1 Make a minimal kernel In the olden days, a Linux kernel image would fit on a single floppy disk. Consult https://elinux.org/Kernel_Size_Tuning_Guide to see how to shrink a custom kernel. 11.10.2 Verify important properties Examples: - Worst-case execution time for key procedures. - No information leakage for key components. 11.10.3 Commercial comparison You might consider mac OS or Windows as comparison operating systems. 11.10.4 For or against certification + certification aids adoption by major commercial/government organizations + increased confidence in correctness of system - certification slows down development, stifles innovation