Downgrade Nix from 25 to 24.11 - kdaisho/Blog GitHub Wiki

Every time I ran home-manager switch I see warnings as home-manager version and nixPkgs version are unmatch.

warning: You are using

  Home Manager version 24.11 and
  Nixpkgs version 25.05.

Using mismatched versions is likely to cause errors and unexpected
behavior. It is therefore highly recommended to use a release of Home
Manager that corresponds with your chosen release of Nixpkgs.

If you insist then you can disable this warning by adding

  home.enableNixpkgsReleaseCheck = false;

to your configuration.

Suppression the warning never be a good idea. I want to fix the problem.

Let's see the both versions:

nix-channel --list

home-manager https://github.com/nix-community/home-manager/archive/release-24.11.tar.gz
nixpkgs https://nixos.org/channels/nixos-unstable/25.05

My Nixpkgs version is unstabled one (version 25?) whereas home-manager is 24.11, stabled one. I want to change (downgrade) nikPkgs to 24.11. how can i do that?

Run these commands and call it a day.

# Switch to nixos-24.11 channel
nix-channel --remove nixpkgs
nix-channel --add https://nixos.org/channels/nixos-24.11 nixpkgs

# Update channels
nix-channel --update

# Clean old packages and update
nix-env --delete-generations old
nix-collect-garbage -d
nix-env -u --always