Not yet, but on the roadmap!

Mh, I thought about this a little and came actually to exactly the opposite conclusion: Implement as much as possible in Rust to get the fastest code possible. Do you have any more insights why this should not be possible / unsustainable?

Why should I want them to use it?

Yeah, I've already looked into it, but decided to keep developing it "example driven" for now. Aka I'm playing around with it, and whenever I find something that's broken I keep a note of it and then I pick those notes one by one and implement them. Once the most common things are implemented I will start writing property tests to catch all the edge cases of each feature.

They rebranded it to Wolfram Language a few years ago (which I actually appreciate, as it is so much more than just "math" by now!)

https://writings.stephenwolfram.com/2013/02/what-should-we-c...