Hi @eskimo, Thank you so much for your quick response! Though I haven't tried the suggested solutions yet, let me answer your below question first. What are you trying to do with a KEXT? Our general advice has always been that you avoid writing code for the kernel if at all possible. Indeed, the first section of the Kernel Programming Guide is entitlement Keep Out! These days you have a wealth of alternatives and it’s best to explore those first. I'm now conducting the feasibility study that implements the "macOS containers" such as the Linux containers below. https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux_atomic_host/7/html/overview_of_containers_in_red_hat_systems/introduction_to_linux_containers To share the context a bit more, I'm working on improving the iOS/macOS app development CI(=Continuous Integration) experience. Due to circumstances, Xcode cloud, on-premise Xcode server, ...etc are not suitable for me. * Actually, for "my development team". Further, hypervisor framework and virtualization framework are not suitable from the performance perspective. Thus I'm exploring the possibility of macOS containerization. To design containerization architecture, it's necessary to know how to handle low-level resources like CPU, I/O, network I/F, ...etc via low-level APIs like the macOS kernel. Learning how to build kernel extension is just the first step of this loooong journey of study. Of course, I understand well that these sorts of low-level implementations are black-boxed, and shouldn't be touched lightly. Nevertheless, I'm curious to seek the way. I also welcome your, and the anyone's thoughts on this topic ;)