nixos-config VS ish

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With NixOS you declare your entire OS in a script, something along the lines of Ansible or Terraform. This can even go as far as configuring your user settings, with dotfiles, gsettings, or various other things (often the modules will expose settings in the native nix language and write out the yaml/toml/json/whatever else that is required). The idiomatic way to do this is to use the built-in NixOS configuration (under /etc/nixos) to set up system-level things: mounts, drivers, users, system-level packages (e.g. greetd+sway), and things that change rarely. You then use a project called home-manager to manage everything inside your user configuration (including applications you use), which itself uses nix. By separating it like this, I can sync my entire experience between my laptop and desktop with Git.

I am currently flighting using a separate "nix flake" for both, which allows you to pin versions of packages (with a lockfile). It also allows you to easily pull in other repositories. It hasn't really taken off yet, and the NUR (Nix User Repository, analogous to the amazing Arch User Repository) is still in infancy. I'd offer up my nix configs as an example, but I am currently in the "make it work" example. I have been yoinking several great ideas from this fantastic nix repo: https://github.com/ymatsiuk/nixos-config

The main challenge with Nix is that it doesn't have an FHS: there is no `/usr`, `/bin`, and what you would typically expect. The advantage here is that conflicting dependency versions are not a problem. The problem is that you need to either build any binaries yourself, or wrap them in an FHS helper.

Nix has a virtualenv system `nix develop` and it's very powerful, especially for teams.

Silverblue

If you're curious, iSH's source is public: https://github.com/ish-app/ish

You're correct that there is no Linux kernel emulation. They went with reimplementation for that. However, the userland is very much emulated x86 binaries. You can even compile your own C code inside iSH and run it. When you syscall, control passes from the threaded code[0] interpreter into the Linux reimplementation.

The reason why they aren't shipping Debian is that the threaded code technique being used as a JIT substitute in both iSH and UTM SE is far too slow to run a full Debian derivative. Believe me, I tried installing Ubuntu on UTM SE and it took literal hours and flattened my iPad battery in the process. iSH uses Alpine Linux because it's very lightweight[1].

As far as I'm aware there's no secret deal with Apple to lock iSH down. The only limitations I've ran into have to do with MySQL, which wants unaligned atomics, which you can't do on ARM64 without compromising the performance of the emulator. I actually had a discussion with the developer of iSH about this and put in a PR to make MySQL stop crashing iSH.

[0] return-oriented programming

[1] So lightweight it doesn't even ship anything GNU, making it one of the few genuine "Linux distros" with no slash or plus or "I would just like to interject"

> in software side of Ipad IOS, that is the biggest innovation in years

That would be iSH, slow but functional Alpine Linux emulation for iOS.

https://ish.app

> Just imagine how much more versatile the iPad Pro would be if only you could run Linux VMs on it

After installing https://ish.app for Alpine Linux emulation on iPad, one immediately comes up with use cases, even though it's excruciatingly slow.

Hopefully Apple opens up the imminent M3 iPad Pros to run macOS and Linux VMs.

iSH

They don't "allow" it, but most apps that need background execution just ask permission for geolocation tracking and pretend to use it, for example iSH[1]. There are a few activities that the app can do to prevent itself from being suspended when it goes out of focus, like playing sound, geolocation etc.

[1] https://github.com/ish-app/ish/issues/249#issuecomment-54433...

Android: install termux, `pkg install openssh`, and preferably run `termux-setup-storage` to give it access to storage folders.

iOS: I think https://ish.app/ ?

This of course hasn't been true for years, eg: http://omz-software.com/pythonista/index.html

And you can run a C compiler (or anything) inside https://ish.app/ too.

False. iSH is an x86 "bytecode" emulator.

"Possibly the most interesting thing I wrote as part of iSH is the JIT. It's not actually a JIT since it doesn't target machine code. Instead it generates an array of pointers to functions called gadgets, and each gadget ends with a tailcall to the next function; like the threaded code technique used by some Forth interpreters."

https://github.com/ish-app/ish

There is an x86 virtual machkne running Linux available on the App Store now.

https://ish.app/

Now would Apple allow a full blown Windows VM is a different question

There are plenty of solutions for running Python in an IDE on the iPad. There is an even an x86 emulator and a Linux terminal built on top of it in the App Store.

https://ish.app/

It can run anything that you can run on an x86 in user mode. I downloaded the AWS CLI (which requires Python) to run some tests

By the way, you were completely wrong about VSCode being written in .Net.

> That's just compiling the code to a native binary, which you would then have to go submit through Apple's store. How does that help for an IDE expected to allow you to test (i.e. execute) and debug the code you've just written ten seconds ago?

There is an existence proof that it could be done. If you ran iSH with remote VNC you could have a full IDE on a Mac.

> We can see right there some examples of what isn't allowed: