Oct 14, 2025

Update nixos

To update Nixos you need to do two things :

Update the channel

sudo nix-channel --update

Apply updates

sudo nixos-rebuild switch

You can do step by step, or just do both in one command line :

nixos-rebuild switch --upgrade

You may reboot to apply major updates (ex : kernel updates).

To upgrade to a new major OS version, you need to add a channel and upgrade :

nix-channel --add https://channels.nixos.org/nixos-<version to upĝrade to ex: 25.05> nixos
sudo nixos-rebuild switch --upgrade

You can also do automatic upgrades by adding the following to your configuration.nix :

{
  system.autoUpgrade.enable = true;
  # Warning "allowReboot = true" allow the upgrade to reboot the machine in order to upgrade the kernel, 
  # if set to false it will stay in the current channel and only upgrade to last version in the current channel.
  system.autoUpgrade.allowReboot = true;
}