Frankly, Rust is fun and I like many concepts. However, I strongly believe that for such low level library we should wait many years in order to make sure that Rust is here to stay for ever (like C does).

The Rust usage could be conditionalized through a build option, and not all files need to be ported to Rust. As we already moved to Meson, it should be fairly straightforward to integrate this kind of hardening:
https://nibblestew.blogspot.com/2021/03/mixing-rust-into-existing-c-shared.html

The candidate files are:

• common/argv.c
• common/array.c
• common/buffer.c
• common/dict.c
• common/path.c
• common/url.c (the hex encoding part)

Most of them would directly map to the Rust's std library.