They're using "no_std" Rust, which is quite bare-bones. Usually the standard library adds 300KB+, but without it it's just cost of the code you add. With a lit

They're using "no_std" Rust, which is quite bare-bones. Usually the standard library adds 300KB+, but without it it's just cost of the code you add. With a little care, you can get the same code size as you'd get in C. https://github.com/johnthagen/min-sized-rust https://github.com/johnthagen/min-sized-rust