Translations:FAQ/117/en: Difference between revisions

Latest revision as of 03:43, 9 September 2024

Message definition (FAQ)

This only changes what version of <code>PACKAGE_NAME</code> is available on <code>$PATH</code>. If the package you want to take from unstable is installed through a NixOS module, you must use [[overlays]]:
<syntaxhighlight lang="nix">
{ config, pkgs, ... }:
let
unstable = import <nixos-unstable> {};
in {
nixpkgs.overlays = [
   (self: super: {
   PACKAGE_NAME = unstable.PACKAGE_NAME;
   })
];
}
</syntaxhighlight>
Note that this will rebuild all packages depending on the overlaid package, which may be a lot. Some modules offer a <code>services.foo.package</code> to change the actual derivation used by the module without and overlay, and without recompiling dependencies ([https://nixos.org/manual/nixos/stable/options.html#opt-services.gvfs.package example]).

This only changes what version of PACKAGE_NAME is available on $PATH. If the package you want to take from unstable is installed through a NixOS module, you must use overlays:

{ config, pkgs, ... }:
let
  unstable = import <nixos-unstable> {};
in {
  nixpkgs.overlays = [
    (self: super: {
       PACKAGE_NAME = unstable.PACKAGE_NAME;
    })
  ];
}

Note that this will rebuild all packages depending on the overlaid package, which may be a lot. Some modules offer a services.foo.package to change the actual derivation used by the module without and overlay, and without recompiling dependencies (example).