A direct comparison like that is somewhat comparing apples to oranges. Don't get me wrong, defaults matter, but Rust still does offer the control required to get small binaries, and, those defaults are not nearly as bad for low-level domains where one isn't using the standard library, which is where binary size is most critical. See also https://lifthrasiir.github.io/rustlog/why-is-a-rust-executab... and even http://mainisusuallyafunction.blogspot.com/2015/01/151-byte-... .