6 ms·

"It is written entirely in Rust, which greatly increases the overall quality and security of the shell." Is this true? I don't know Rust so I'm probably missin

by mtillman 10mo ago

"It is written entirely in Rust, which greatly increases the overall quality and security of the shell." Is this true? I don't know Rust so I'm probably missing context. Obvious kudos to OP for writing a shell.

killme2008 10mo ago
Yeah, that’s true — Microsoft’s report (https://www.microsoft.com/en-us/msrc/blog/2019/07/why-rust-for-safe-systems-programming https://www.microsoft.com/en-us/msrc/blog/2019/07/why-rust-f...) says the same thing, and Google’s recent post on Rust in Android (https://security.googleblog.com/2025/11/rust-in-android-move-fast-fix-things.html https://security.googleblog.com/2025/11/rust-in-android-move...) backs it up too. We’ve been using Rust for about seven years now, and as long as you stay away from fancy unsafe tricks, you really can avoid most memory safety bugs.
ablob 10mo ago
It's true for new projects. For rewrites (such as a shell) it can mean a lot of regressions. The rust-replacements for coreutils are a good negative example. The new programs do not reach feature-parity, added regressions, and in some cases also had security vulnerabilities. So for battle-proved software I wouldn't say so per-se (if your goal is to replace them). Nonetheless, if you add truly new rust-code to a new or existing codebase when it's without much of hassle with the interop it should hold.
zie 10mo ago
You get memory safety. That's about it for Security. Quality is in the eye of the beholder. maybe it's quality code? Maybe it's junk, who knows. Rust isn't magic that forces code to be quality code or anything. That said, the code in the Redox system is generally good, so it's probably fine, but that's not because it's written in Rust, it's because of the developers. Any GC'd language(Python, JS, Ruby, etc) gives you the same memory safety guarantees that Rust gives you. Of course GC'd languages tend to go a fair bit slower(sometimes very drastically slower) than Rust. So really the memory safety bit of Rust is that the memory safety happens at develop and compile time, instead of at runtime, like a GC language does. So you get the speed of other "systems" languages, like C, C++, etc AND memory safety.
- Philpax 10mo ago
  > Rust isn't magic that forces code to be quality code or anything. It is not, but the language and ecosystem are generally very well-designed and encourage you to "do the right thing," as it were. Many of the APIs you'd use in your day-to-day are designed to make it much harder to hold them wrong. On balance, outside of Haskell, it's probably the implementation language that fills me with the most confidence for any given particular piece of software.
  - johnisgood 10mo ago
    I do not think that using dependencies like it is npm is "doing the right thing".
- vlovich123 10mo ago
  While I generally agree, the latest Android report suggests that rust developers get fewer reverts and code reviews are faster. This could mean that better developers tend to adopt rust or it could mean that rust really is a language where quality is easier to attain. There’s some reason to believe that given how easy it is to integrate testing into the rust code base and in general the trait and class system is also a bit higher quality and it encourage better isolation and things like const by default and not allowing API that could misuse the data structure in some unsafe way. And it has a rich ecosystem that’s easy to integrate 3p dependencies so that you’re not solving the same problem repeatedly like you tend to do in c++ So there is some reason to believe Rust does actually encourage slightly higher quality code out of developers.
  - ok123456 10mo ago
    Or there are "reverts and code reviews are faster" because no one wants to actually read through the perl-level line-noise type annotations, and just lgtm.
    - oersted 10mo ago
      What type annotations? In Rust almost all the types are inferred outside of function and struct declarations. In terms of type verbosity (in the code) it is roughly on the same level as TypeScript and Python.
deleted 10mo ago
[deleted]
handwarmers 10mo ago
Not necessarily. "Quality" and "Security" can be tricky subjects when it comes to a shell. Rust itself is pretty great, but its HN community is made of cringe and zealotry - don't let them dissuade you from trying the language :P

killme2008 10mo ago

Yeah, that’s true — Microsoft’s report (https://www.microsoft.com/en-us/msrc/blog/2019/07/why-rust-for-safe-systems-programming https://www.microsoft.com/en-us/msrc/blog/2019/07/why-rust-f...) says the same thing, and Google’s recent post on Rust in Android (https://security.googleblog.com/2025/11/rust-in-android-move-fast-fix-things.html https://security.googleblog.com/2025/11/rust-in-android-move...) backs it up too. We’ve been using Rust for about seven years now, and as long as you stay away from fancy unsafe tricks, you really can avoid most memory safety bugs.

ablob 10mo ago

It's true for new projects. For rewrites (such as a shell) it can mean a lot of regressions. The rust-replacements for coreutils are a good negative example. The new programs do not reach feature-parity, added regressions, and in some cases also had security vulnerabilities. So for battle-proved software I wouldn't say so per-se (if your goal is to replace them). Nonetheless, if you add truly new rust-code to a new or existing codebase when it's without much of hassle with the interop it should hold.

zie 10mo ago

You get memory safety. That's about it for Security. Quality is in the eye of the beholder. maybe it's quality code? Maybe it's junk, who knows. Rust isn't magic that forces code to be quality code or anything. That said, the code in the Redox system is generally good, so it's probably fine, but that's not because it's written in Rust, it's because of the developers. Any GC'd language(Python, JS, Ruby, etc) gives you the same memory safety guarantees that Rust gives you. Of course GC'd languages tend to go a fair bit slower(sometimes very drastically slower) than Rust. So really the memory safety bit of Rust is that the memory safety happens at develop and compile time, instead of at runtime, like a GC language does. So you get the speed of other "systems" languages, like C, C++, etc AND memory safety.

Philpax 10mo ago
> Rust isn't magic that forces code to be quality code or anything. It is not, but the language and ecosystem are generally very well-designed and encourage you to "do the right thing," as it were. Many of the APIs you'd use in your day-to-day are designed to make it much harder to hold them wrong. On balance, outside of Haskell, it's probably the implementation language that fills me with the most confidence for any given particular piece of software.
- johnisgood 10mo ago
  I do not think that using dependencies like it is npm is "doing the right thing".
vlovich123 10mo ago
While I generally agree, the latest Android report suggests that rust developers get fewer reverts and code reviews are faster. This could mean that better developers tend to adopt rust or it could mean that rust really is a language where quality is easier to attain. There’s some reason to believe that given how easy it is to integrate testing into the rust code base and in general the trait and class system is also a bit higher quality and it encourage better isolation and things like const by default and not allowing API that could misuse the data structure in some unsafe way. And it has a rich ecosystem that’s easy to integrate 3p dependencies so that you’re not solving the same problem repeatedly like you tend to do in c++ So there is some reason to believe Rust does actually encourage slightly higher quality code out of developers.
- ok123456 10mo ago
  Or there are "reverts and code reviews are faster" because no one wants to actually read through the perl-level line-noise type annotations, and just lgtm.
  - oersted 10mo ago
    What type annotations? In Rust almost all the types are inferred outside of function and struct declarations. In terms of type verbosity (in the code) it is roughly on the same level as TypeScript and Python.

deleted 10mo ago

[deleted]

handwarmers 10mo ago

Not necessarily. "Quality" and "Security" can be tricky subjects when it comes to a shell. Rust itself is pretty great, but its HN community is made of cringe and zealotry - don't let them dissuade you from trying the language :P