You're asking for enterprise-grade, production ready kernels, and immediately after say Rust is nearing maturity. There you go.

Writing a kernel is like building a cathedral. To have a production ready kernel, set aside 15 years, or the equivalent in dollars, at least a couple billion. This is why stuff like Serenity, which is an outstanding achievement, is not much more than a toy.

We will have a Rust based kernel that is memory safe. Not this decade though. By that time Linux will have replaced more and more subsystem with Rust already. Remember, enterprise grade means boring and stable. It is nonsense to want a new, unproved kernel to provide that level of safety out of a language that has reached 1.0 not very long ago.

Personally, I think Linux is plenty good enough, but we have seen the best UNIX can offer. It's time to move on and try something new.

> By that time Linux will have replaced more and more subsystem with Rust already.

Honestly, this is a bold prediction, maybe a foregone conclusion to some, but not everybody. It completely remains to be seen.

> It is nonsense to want a new, unproved kernel to provide that level of safety out of a language that has reached 1.0 not very long ago.

Perhaps - but the Rust community has been very vocal for a very long time about how much of an improvement over C/C++ it was already before it reached 1.0. I'm not asking for an "enterprise-grade" kernel yet, just signs of prototypes starting to emerge and the community gathering round them. I realise I worded that badly in my initial post.

New C/C++/asm based hobby kernels are started (and abandoned) everyday on /r/osdev. Nowhere near as many in Rust by a wide margin. Instead the Rust community seems to have placed all their bets on an "outside in" rewrite of the Linux kernel in Rust. While I think this may well be great for Linux in the long term, its a little dissapointing that there is not more momentum for "from scratch" projects yet. Even Linux started as "as hobby, not big and professional like GNU". Which leads to my next point ...

> Personally, I think Linux is plenty good enough, but we have seen the best UNIX can offer. It's time to move on and try something new.

Don't disagree at all. That's why I'm surprised there aren't more up and coming projects in Rust with brand new designs to the degree that there are in C/C++. That's all. Maybe they are there, and I'm just not seeing them.

I think you may just be not looking where the rust people are posting. All you're really saying is that they aren't on /r/osdev, and frankly I don't find that surprising. Here are some of the more flagship projects

The biggest rust kernel/os project I'm aware of is https://www.redox-os.org/

It's a bit out of date by now, but this is an excellent guide written in rust: https://os.phil-opp.com/minimal-rust-kernel/

On the embedded side, this is a commercial project that actually "matters": https://github.com/oxidecomputer/hubris

This is a uni-kernel that I've heard about quite a few times: https://github.com/hermitcore/rusty-hermit

Naturally there's a bunch more smaller projects, and maybe larger ones that I haven't heard of.