Installed NixOS Vicuna from the list of unstable ISOs

Help
1

I installed NixOS Vicuna from a pre-released ISO on the channels website. But when I installed it from the same dotfiles of 24.05, I forgot to change the system.stateVersion. What can I expect? I have run into a few problems. Like not being able to build hy3 plugins because of libpcre2-8 not being found. What should I do? (After realizing the mistake, I changed the stateVersion.)

2

You shouldn’t touch it, like ever.
This comment should be a part of every configuration generated by nixos-generate-config:

  # This option defines the first version of NixOS you have installed on this particular machine,
  # and is used to maintain compatibility with application data (e.g. databases) created on older NixOS versions.
  #
  # Most users should NEVER change this value after the initial install, for any reason,
  # even if you've upgraded your system to a new NixOS release.
  #
  # This value does NOT affect the Nixpkgs version your packages and OS are pulled from,
  # so changing it will NOT upgrade your system - see https://nixos.org/manual/nixos/stable/#sec-upgrading for how
  # to actually do that.
  #
  # This value being lower than the current NixOS release does NOT mean your system is
  # out of date, out of support, or vulnerable.
  #
  # Do NOT change this value unless you have manually inspected all the changes it would make to your configuration,
  # and migrated your data accordingly.
  #
  # For more information, see `man configuration.nix` or https://nixos.org/manual/nixos/stable/options#opt-system.stateVersion .
  system.stateVersion = "24.05"; # Did you read the comment?
3

@woodenAllen I don’t think you’ve understood what stateVersion is. Read about it here: Appendix A. Configuration Options

It doesn’t affect the evaluation or building of packages. It only affects the stateful data that’s on the system and how NixOS is configured to handle that state. If a package is failing to build, it’s not because of stateVersion.

4

Yes. I did read that somewhere. The problem is exactly that. I installed NixOS from the nixos-24.11preXXXX ISO file. But in my configuration.nix, forgot to change the stateVersion from 24.05 to 24.11 (because I just git pulled, replaced old hardware-configuration.nix with the new one and forgot to the aforementioned step) and just went with the nixos-install. BTW, has anyone tried installing from the pre-released ISOs? Is it recommended or done widely?

5

It’s completely fine to install with an older stateVersion than the version you’re installing. If the install was done with an older stateVersion, you still should not change it afterwards, because now you potentially already have state dependent on the original stateVersion.

The unstable ISO are expected to be as high quality as the stable ones.