Explore the intricate relationship between operating system kernels and language run-times in this 30-minute conference talk from linux.conf.au 2020. Delve into how kernel design influences run-time development, essential components for software creation, and the impact of existing design choices on software portability. Examine specific examples including Rust on Linux, freestanding C18 embedded applications, and microkernel development with seL4. Gain insights into building operating system components, creating OS personalities, and understanding the requirements for 'portable' run-times. Learn how these factors shape the future of programming languages and kernel development in the open-source ecosystem.