NixOS

Install

Switch to azerty keyboard
```
→ loadkeys be-latin1
```
Partition with gdisk (efi) or fdisk (noefi)

using virtualbox you don’t want/need efi
```
→ (g/f)disk /dev/sda
```
Create 2 partitions sda1(83 default)/sda2(82).

[efi] Create an extra (boot) partition with type EF00.

Create file system

→ mkfs.ext4 -L nixos /dev/sda1
→ mkswap -L swap /dev/sda2

[efi] Choose vfat.

Mount it
```
→ mount /dev/disk/by-label/nixos /mnt
```
[efi] mkdir /mnt/boot and mount the boot partition in.
Generate a default config
```
→ nixos-generate-config --root /mnt
```
Minimal edit the config; don’t forget to uncomment the option 'boot.loader.grub.device'
```
→ vim /mnt/etc/nixos/configuration.nix
```
[efi] No edit required.
Install
```
→ nixos-install
```
Reboot
```
→ reboot
```

Upgrade

→ nixos-rebuild boot --upgrade
→ reboot

Configuration

Configuration

Some nix properties are set up in /etc/nix/nix.conf

for wifi, manually configure it by using NetworkManager through the nmtui text interface

/etc/nixos/configuration.nix

  nixpkgs.config.allowUnfree = true;

  i18n = {
    consoleFont = "Lat2-Terminus16";
    consoleKeyMap = "be-latin1";
    defaultLocale = "en_US.UTF-8";
  } ;

  environment.systemPackages = with pkgs; [
    asciidoctor (1)
  ];

  # Define a user account. Don't forget to set a password with ‘passwd’.
  users.extraUsers.nix = { (2)
    createHome = true;
    home = "/home/nix";
    isSystemUser = true;
    extraGroups = [ "wheel" "disk" "vboxusers" "docker"];
    shell = "/run/current-system/sw/bin/bash";
    uid = 1000;
  };

  programs.bash.enableCompletion = true;
  security.sudo.wheelNeedsPassword = false;

  fonts = {
    enableFontDir = true;
    fonts = [ pkgs.source-code-pro ];
  };

  nix.extraOptions = ''
    gc-keep-outputs = true (3)
    gc-keep-derivations = true (3)
  '';

  virtualisation.docker.enable = true;
  virtualisation.docker.extraOptions = "--insecure-registry x.lan --insecure-registry y.lan";

  virtualisation.virtualbox.guest.enable = true; (4)
  boot.initrd.checkJournalingFS = false; (4)

1	add packages
2	do create a new user ! (root won’t be able to have a chromium session by default)
3	prevent too much gc in developer environment
4	virtualbox only

System management

Update

→ sudo nixos-rebuild switch
→ sudo nixos-rebuild boot --upgrade (1)

1	safer to use `boot` when upgrading

Channels

A channel is the Nix mechanism for distributing a consistent set of Nix expressions and binaries. nix-channel --add

→ nix-channel --add http://nixos.org/channels/nixpkgs-unstable
→ nix-channel --update
→ nixos-rebuild switch

The unstable channel is usually a few days older from nixpkgs master. For a precise status, check here.

You can directly use a derivation from master. For instance, after cloning nixpkgs, you could type:

→  NIX_PATH=nixpkgs=/home/vagrant/projects/nix/nixpkgs nix-env -f '<nixpkgs>' -iA haskellPackages.stack

In future version of nix, channel might be deprecated to favor NIX_PATH solely.
On nixos, you should stick to nixos-unstable (don’t use nixpkgs-unstable because specific nixos sanity check won’t applied)

Nix modules

A NixOS module is a file that handles one logical aspect of the configuration.

{ config, lib, pkgs, ... }: (1)

{
  imports = (2)
    [
    ];

   options.services.foo = { (3)
    enable = mkOption {
      type = types.bool;
      default = false;
      description = ''

      '';
    };
    ...
  };

  config = mkIf config.services.foo.enable { (4)
    environment.systemPackages = [ ... ];
  };
}

1	function declaration with access to the full system configuration and nixpkgs
2	paths to other modules that should be included in the evaluation
3	options declaration
4	option definition