I think he's always been OK with C++, Python, Rust etc., for tooling around the kernel. But found that for the kernel itself, the performance and reliability gu

I think he's always been OK with C++, Python, Rust etc., for tooling around the kernel. But found that for the kernel itself, the performance and reliability guarantees were strict enough that he didn't want to risk there being performance or reliability issues caused by the compiler. Performance/reliability issues caused by programmers can be found and rectified. Performance issues caused by compilers may not be replicable even between builds.