noah VS rust

The other day I came across an interesting "alternative" to WASM which gives you OS portability using fully native code, without CPU portability, the latter seeming not that big of a deal these days anyway as cross compilers have got quite good and there are only two CPU archs in wide usage anyway.

The idea is to simply run normal Linux binaries on macOS and Windows. How? You create a virtual machine using the Mac/Windows APIs without any OS inside, in fact without even any virtual hardware. It's literally just a new address space and some trivial min-viable VM configuration. Then you map the ELF binary and a ld.so into the VM with a minimal ELF interpreter, kick off execution and anytime there's a syscall you trap it and translate to the host OS syscalls. It can work quite well on macOS because the syscall interface is so similar.

Note that this sort of VM is not:

• A sandbox

• A hardware abstraction

Apps run this way hold all their data in the filing system of the host OS, they use the network stack of the host OS, etc. The VM is only being used to allow trapping and emulation of the syscall interface. The app isn't aware that it's being run in a special CPU mode on top of an emulated kernel.

Advantages: lightweight, simple, apps can use all CPU features, can run at native speed, the Linux syscall interface is highly stable, based on POSIX specifications and you can easily pick a subset of it to standardize.

Disadvantages: requires the emulator, apps exposed to missing features or quirks of the host OS e.g. Windows file system performance is much lower than Linux.

WSL1 sort of worked that way, albeit without the VM aspect that lets userspace apps do it. They abandoned it partly for performance reasons and users expected all existing Linux apps to just work. But WASM doesn't target existing apps. It expects developers to bend and do things the WASM way, and accepts that not all apps are compatible with it, so that's not necessarily a problem.

An example of how to implement this is NOAH:

https://github.com/linux-noah/noah/

There was an attempt, but it was archived https://github.com/linux-noah/noah

If you haven't dipped your touch-typing fingers into Rust yet, you really owe it to yourself. Rust is a modern programming language with features that make it suitable not only for systems programming -- its original purpose, but just about any other environment, too; there are frameworks that let your build web services, web applications including user interfaces, software for embedded devices, machine learning solutions, and of course, command-line tools. Since a custom GitHub Action is essentially a command-line tool that interacts with the system through files and environment variables, Rust is perfectly suited for that as well.

Here's an example of someone citing a disagreement between CRT and shell32:

https://github.com/rust-lang/rust/issues/44650

This in addition to the Rust CVE mentioned elsewhere in the thread which was rooted in this issue:

https://blog.rust-lang.org/2024/04/09/cve-2024-24576.html

Here are some quick programs to test contrasting approaches. I don't have examples of inputs where they parse differently on hand right now, but I know they exist. This was also a problem that was frequently discussed internally when I worked at MSFT.

    #include 

> instead of choosing a certain numbered version of the random library (if I remember correctly) I let cargo download the latest version which had a completely different API.

Yeah, they didn't follow the instructions and got burned. I still think that multiple things went wrong simultaneously for that experience. I wonder if more prevalent uses of `#[doc(alias = "name")]` being leveraged by https://github.com/rust-lang/rust/pull/120730 (which now that I check only accounts for methods and not functions, I should get on that!) so that when changing APIs around people at least get a slightly better experience.

Almost fixed the compiler: https://github.com/rust-lang/rust/pull/123325

Rust: A secure, efficient, and modern programming language (omitting ten thousand words). You can simply follow the installation instructions provided on the official website.

Recently did something similar in Rust but for generating SVGs. We've adopted it for snapshot testing of cargo and rustc's output. Don't have a good PR handy for showing Github's rendering of changes in the SVG (text, side-by-side, swiping) but https://github.com/rust-lang/rust/pull/121877/files has newly added SVGs.

To see what is supported, see the screenshot in the docs: https://docs.rs/anstyle-svg/latest/anstyle_svg/

We strongly believe in Rust as a powerful language for building production-grade software, especially for systems like ours that run alongside Kubernetes.

The above Assert<{N % 2 == 1}> requires #![feature(generic_const_exprs)] and the nightly toolchain. See https://github.com/rust-lang/rust/issues/76560 for more info.