Why use Nix/NixOS?

A reasonable question! Why use any of this? Why abandon everything you know about Linux and use this niche operating system? Well, to understand, we must first look at the advantages of Nix, the powerful package manager NixOS is built on.

Nix advantages:

  • The Nix Store: Nix stores all packages in a special folder called the nix store, which exists in the /nix directory. In the nix store, a package is built along with its dependencies, and stored as a hash. The store is read-only, meaning no modifications can be made to it without specialized commands, even as root!
  • Atomic updates: when packages installed by Nix need to update, Nix will not allow updates to occur unless all of them are successful. This eradicates broken packages being an issue. If a package refuses to build, just wait for the next update when they fix it! These usually take only a couple of days, during which your system will be fully usable and not broken.
  • Reproducible builds: when Nix builds a package, it will build exactly the same result on any system that package is built on.
  • Single package manager to rule them all: tired of using NPM, pip, the AUR, and all these other package managers? We were too! That’s why we are very happy to say that Nix has more than 100,000 packages to install, and is the most up-to-date package manager in existence! We like to think of it as the Rule 34 of package managers: if it exists, it’s in nixpkgs. If it isn’t in nixpkgs, it will be added.
  • Great for development: development is a major reason for Nix’s existence! With tools like direnv, making dev environments is easy and benefits from all that Nix has to offer.
  • Easy to try out packages without installing using nix shell or nix run: have you ever wanted to try out a program from, let’s say, KDE? On other systems, it requires fully installing all of KDE’s dependencies. Then, if you don’t like the program and uninstall it, you still have those dependencies on your system. But using the above commands, you can quickly and effectively try out any program you like. If you don’t like it, no problem! It won’t stay on your system when you remove it.
  • Uses binary caches: Nix automatically builds packages in its repository remotely, meaning compiling for anything in nixpkgs is is unnecessary! Need a binary cache for your own program? You can set that up easily too!
  • Portable: Nix runs on anything: Linux, MacOS, WSL, there’s even a project called nix-on-droid that lets you use it on Android.
  • Mix and match different package versions without conflicts: since packages are built independently of each other, dependencies and all, you can have multiple versions of a package. It isn’t anything you need to set up either. That’s just how it is.

So, now that you know why you should use Nix, why use NixOS?

NixOS advantages:

  • Declarative configuration: the central feature of NixOS, other than the package manager, is the module system. Modules are pretty much a fancy term for options. In your NixOS configuration, you can reference one of the thousands of modules NixOS has for applications. This has two advantages:
    • Easy configuration: Gone are the days of setting up services manually or using docker containers. With NixOS, as long as the module exists, you can do all of that with a few lines of code.
    • Easier to maintain the configuration: since your configuration is a few lines of code and always in the same directory you left it in, there’s no need to run a multitude of commands in an effort to solve problems. All you have to do is change some values in your NixOS configuration.
  • Reproducible system: this is one of the crowning features of NixOS: taking the reproducibility of Nix to the OS level. You can back up your configuration to a git repository and place it on however many computers you like, and it’ll be the exact same operating system every single time, minus your home directory. This makes backups a breeze.
  • Out of the box rollbacks: another crowning feature of NixOS, and any immutable distro. Is there an issue with your current system? No problem! Just rollback to a previous system either from a terminal or at boot time and you’ll be good to go!
  • Configuration options for many programs & services: there are thousands of modules in NixOS, and thousands of options to choose from, all written in a single language.
  • Free of side effects - Actually uninstalls packages and their dependencies: since dependencies are installed and stored with the packages that need them, this also means that no dependencies will be left behind when you uninstall a package. And any useless store directories can be cleaned up using nix-collect-garbage.
  • Easy to set up VMs: you can set up QEMU/KVM easily using the module! No more fussing around with systemd stuff or a clunky GUI. Nix can do it all!
  • Test other configurations: remember nix shell and nix run? Both of these commands can also build configurations from a URL! Just point to the git repo where the configuration is, and Nix will do the rest.

If any of these sound good to you, head on over to the next page where we’ll cover how to install NixOS on your machine.