I <3 unattended upgrades!

my current nixos configuration setup:

• ~/git/nixos/nixos-auto-upgrades.md
• ~/git/nixos/flake.nix
• ~/git/nixos/g14.nix

symlinked to:

• /etc/nixos/configuration.nix
• /etc/nixos/flake.nix
• /etc/nixos/g14.nix

Enter Nix #2: Flakes and Automatic System Upgrades

1. enable flakes

g14 is my hostname, you need to change it to your hostname

{
  description = "A very basic flake";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
  };

  outputs = {
    self,
    nixpkgs,
  }: {
    nixosConfigurations.g14 = nixpkgs.lib.nixosSystem {
      system = "x86_64-linux";
      modules = [./configuration.nix];
    };
  };
}

2. add auto upgrade service

system.autoUpgrade = {
    enable = true;
    randomizedDelaySec = "30min"; # Adds a random delay to prevent simultaneous updates
    dates = "daily"; # or "weekly", "monthly", etc.
    flags = ["--impure" "--flake" "/etc/nixos"];
    allowReboot = true; # Allow the system to reboot if necessary
    # email = "your-email@example.com"; # Uncomment to receive email notifications
    # emailOnFailure = true;
};

also, you need to change your rebuild command to:

$ nixos-rebuild switch --flake /etc/nixos

if you get the error "Failed to start nvidia-powerd service.", add this line to your configuration.nix.

hardware.nvidia.dynamicBoost.enable = false;

To see the status of the timer run

$ systemctl status nixos-upgrade.timer

The upgrade log can be printed with this command

$ systemctl status nixos-upgrade.service

useful links:

• https://nixos.wiki/wiki/Flakes
• https://nixos.wiki/wiki/Automatic_system_upgrades
• https://aires.fyi/blog/why-is-enabling-automatic-updates-in-nixos-hard/