graviola

You might like https://github.com/ctz/graviola/ Also, even if rustls is using aws-lc-rs, you still get the TLS parts from the rustls project, and aws-lc-rs is just lower-level crypto. That means there's less places for Amazon to say no; they either implement an algorithm or don't.

Note that all cryptographic primitives are still going to be in C via an OpenSSL-like API for the next while; the current proposal is to migrate from OpenSSL to one of its forks. Various bits of backend logic that aren't cryptographic primitives (e.g., parsing) have been rewritten in Rust; additionally, https://github.com/ctz/graviola is mentioned near the end as a possible implementation of cryptographic primitives in a combination of Rust and assembly (without any C), but it's not especially mature yet.

I think what you're quoting says what I was saying - assembly with some C around it, wrapped in a Rust API. At least for the "select" (read: most important) algorithms. The details of the C/asm boundary in aws-lc are hard to summarize. Ideally the C would eventually move to Rust, but I think aws-lc needs to work in many contexts where a Rust toolchain is not available so it might be a while. Graviola is an interesting option under development, in part because it gets rid of the C: https://github.com/ctz/graviola