> I just built a Rust executable that runs on six operating systems
I help maintain a kernel in C that runs on nine architectures, some of which don't even have LLVM backends, much less stable rust toolchains.
"Portable" means rather different things. This blog post is focused on the easy stuff.
They didn't build six executables that run on six operating systems. Rather, it's a single nativity compiled executable that runs on six different operating systems unmodified.
Cosmopolitan is an incredibly cool project that does more than you think.