Upgrading NixOS is a straightforward process, but it’s important to follow the correct steps to ensure a smooth transition. Here is a guide on how to upgrade your system to NixOS 25.11.
1. List Current Channels
First, it’s a good idea to verify your current channels.
nix-channel --list
2. Add the New 25.11 Channel
Add the new NixOS 25.11 channel to your system.
sudo nix-channel --add https://nixos.org/channels/nixos-25.11 nixos
3. Update All Channels
Update your channels to download the new package definitions.
sudo nix-channel --update
4. Read the Release Notes
Crucial Step: Before proceeding, make sure to read the release notes for any breaking changes that might affect your configuration.
Check the release notes at: nixos.org/manual/nixos/25.11/release-notes
5. Rebuild Your System
Now, rebuild your system. This process will take some time as it downloads and compiles the new packages.
Use the --upgrade flag to automatically apply fixes for some common changes.
sudo nixos-rebuild switch --upgrade
Alternatively, if you want to build and boot into the new system without activating it immediately:
sudo nixos-rebuild boot --upgrade
6. Reboot
If you used the boot command or want to be fully on the new system, perform a reboot.
sudo reboot