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[[{{PAGENAME}}]] (/(ɡ)noʊm/) is a [[:Category:Desktop environment|desktop environment]] for both [[Wayland]] and [[Xorg]] that seeks to be "an independent computing platform for everyone."<ref>Official GNOME Project one-liner https://www.gnome.org/ </ref>  
[[{{PAGENAME}}]] (/(ɡ)noʊm/) is a [[:Category:Desktop environment|desktop environment]] that seeks to be "an independent computing platform for everyone."<ref>Official GNOME Project one-liner https://www.gnome.org/ </ref>


This article is an extension of the documentation in the [https://nixos.org/manual/nixos/stable/#chap-gnome NixOS manual].
This article is an extension of the documentation in the [https://nixos.org/manual/nixos/stable/#chap-gnome NixOS manual].
Line 5: Line 5:
== Installation ==
== Installation ==


To use GNOME on NixOS, the following configuration options must be set:
=== GNOME desktop ===
To use the GNOME desktop environment on NixOS, the following configuration options must be set:
 
{{file|3={ config, pkgs, ... }:


{{file|/etc/nixos/configuration.nix|nix|<nowiki>
{
{
   # Pre 25.11
   # Pre 25.11
   services.xserver.enable = true;
   services.xserver.enable = true;
Line 17: Line 20:
   services.displayManager.gdm.enable = true;
   services.displayManager.gdm.enable = true;
   services.desktopManager.gnome.enable = true;
   services.desktopManager.gnome.enable = true;
}
</nowiki>}}


Despite the options in NixOS versions before 25.11 being under the <code>xserver</code> namespace, GNOME runs offers [[Wayland]] by default. 25.11 and later versions remove support for the [[Xorg]] session entirely (though Xwayland is still included and supported for compatibility).
  # To disable installing GNOME's suite of applications
  # and only be left with GNOME shell.
  services.gnome.core-apps.enable = false;
  services.gnome.core-developer-tools.enable = false;
  services.gnome.games.enable = false;
  environment.gnome.excludePackages = with pkgs; [ gnome-tour gnome-user-docs ];
 
}|name=/etc/nixos/configuration.nix|lang=nix}}
 
Despite the options in NixOS versions before 25.11 being under the <code>xserver</code> module, GNOME uses [[Wayland]] by default. NixOS 25.11 and later removes support for the [[Xorg]] session entirely (though Xwayland is still included and supported for compatibility).


=== GNOME Extensions ===
=== GNOME extensions ===
GNOME offers support for changing/overhauling the user interface (GNOME Shell) through the use of ''[https://extensions.gnome.org/about/ Extensions].'' Extensions are bundles of third-party [https://gjs.guide/extensions/ GJS] modules that are loaded while GNOME is running to augment the user experience. A repository of GNOME extensions can be found on GNOME's official [https://extensions.gnome.org/ webpage] and can be installed imperatively if needed by unpacking the extension in <code>~/.local/share/gnome-shell/extensions</code> directory. Extensions can only be activated if it supports the GNOME release that it's installed alongside with.
GNOME offers support for changing/overhauling the user interface (GNOME Shell) through the use of ''[https://extensions.gnome.org/about/ Extensions].'' Extensions are bundles of third-party [https://gjs.guide/extensions/ GJS] modules that are loaded while GNOME is running to augment the user experience. A repository of GNOME extensions can be found on GNOME's official [https://extensions.gnome.org/ webpage] and can be installed imperatively if needed by unpacking the extension in <code>~/.local/share/gnome-shell/extensions</code> directory. Extensions can only be activated if it supports the GNOME release that it's installed alongside with.


However, Nix automatically packages all available GNOME extensions under the <code>pkgs.gnomeExtensions</code> attribute. Extensions which require additional dependencies are then manually packaged if needed. Installed extensions can be enabled graphically through the built-in "Extensions" application or through the <code>gnome-extensions</code> command line interface.
In addition, NixOS automatically packages all officially available GNOME extensions under the <code>pkgs.gnomeExtensions</code> attribute. Extensions which require additional dependencies are then manually packaged if needed. Installed extensions can be enabled graphically through the built-in "Extensions" application or through the <code>gnome-extensions</code> command line interface.


{{file|/etc/nixos/configuration.nix|nix|<nowiki>
{{file|3={
{
   environment.systemPackages = with pkgs; [
   environment.systemPackages = with pkgs; [
     gnomeExtensions.blur-my-shell
     gnomeExtensions.blur-my-shell
Line 34: Line 43:
     gnomeExtensions.arc-menu
     gnomeExtensions.arc-menu
   ];
   ];
}
}|name=/etc/nixos/configuration.nix|lang=nix}}
</nowiki>}}
== Configuration ==
== Configuration ==


=== Managing extensions ===
=== dconf ===


Installed extensions can be enabled and configured in Extension app that comes preinstalled with GNOME. If you want to do that declaratively in your configuration, you can use [[Home Manager]] <code>dconf</code> module by adding following lines.
Dconf is a low-level configuration system for storing and loading configurations. The dconf database is stored in a single binary file in <code>~/.config/dconf/user</code> and contains all known configuration values for all applications and programs that use dconf (GNOME applications and shell, gtk, etc).


{{file|~/.config/home-manager/home.nix|nix|<nowiki>
For example, the setting which controls the accent color of GNOME shell is located in the ''schema'' labeled <code>/org/gnome/desktop/interface/</code> which contains the ''key'' <code>accent-color</code> which accepts a GVariant ''value'' of type <code>enum</code> (one of <code>'blue'</code>, <code>'teal'</code>, <code>'green'</code>, etc)
{
 
NixOS and Home Manager both provide an interface for declarative configuration of dconf settings exposed in <code>programs.dconf</code> and <code>dconf</code> modules respectively.
 
Going back to the previous example, to set the accent color of GNOME in a declarative manner in NixOS as well as mapping the keyboard's "caps lock" key to "ctrl" you would write:
 
{{file|3={
  programs.dconf.profiles.user.databases = [
    {
      lockAll = true; # prevents overriding
      settings = {
        "org/gnome/desktop/interface" = {
          accent-color = "blue";
        };
        "org/gnome/desktop/input-sources" = {
          xkb-options = [ "ctrl:nocaps" ];
        };
      };
    }
  ];
}|name=/etc/nixos/configuration.nix|lang=nix}}
 
And the equivalent snippet in Home Manager:
 
{{file|3={
  dconf.enable = true;
  dconf.settings = {
    "org/gnome/desktop/interface" = {
      accent-color = "blue";
    };
    "org/gnome/desktop/input-sources" = {
      xkb-options = [ "ctrl:nocaps" ];
    };
  };
}|name=~/.config/home-manager/home.nix|lang=nix}}Thus the settings attribute accepts an attribute set whose keys are schemas with each schema's value being a nested attribute set of the schema's keys with their appropriate GVariant value.{{Note|Schemas in Nix are written without leading and trailing slashes. In addition, since dconf have more data types than the Nix language (for example, tuples), in some cases you'll need to convert Nix value to a GVariant value. You can achieve that by using the functions defined under <code>lib.gvariant</code>, they're documented [https://nixos.org/manual/nixpkgs/stable/#sec-functions-library-gvariant here].}}If you wish to revert all dconf settings back to their default state (reset GNOME essentially) then use the following command which  resets all schemas directories available on your system, note that this will affect all programs that use dconf, including GNOME apps and extensions.<syntaxhighlight lang="bash">
$ dconf reset -f /
</syntaxhighlight>
 
==== Extensions ====
Extensions are not activated by default when installed with Nix but can be configured to do so using the respective dconf modules. The schema is <code>/org/gnome/shell/</code> with the key <code>enabled-extensions</code> which accepts a list of strings that represent extension UUIDs. If the extension was installed with Nix, then the UUID can be accessed by the <code>extensionUuid</code> attribute of the extension itself. Each extension's configuration can then be found under their corresponding schema in <code>/org/gnome/shell/extensions/</code> and be configured as needed.
 
For example, in Home Manager, you could write:
 
{{file|3={
   dconf = {
   dconf = {
     enable = true;
     enable = true;
     settings = {
     settings = {
       "org/gnome/shell" = {
       "org/gnome/shell" = {
         disable-user-extensions = false; # enables user extensions
         # disable-user-extensions = true; # Optionally disable user extensions entirely
         enabled-extensions = [
         enabled-extensions = [
           # Put UUIDs of extensions that you want to enable here.
           # Put UUIDs of extensions that you want to enable here.
Line 55: Line 105:
           # field (look at the following example).
           # field (look at the following example).
           pkgs.gnomeExtensions.gsconnect.extensionUuid
           pkgs.gnomeExtensions.gsconnect.extensionUuid
         
 
           # Alternatively, you can manually pass UUID as a string.
           # Alternatively, you can manually pass UUID as a string.
           "blur-my-shell@aunetx"
           "blur-my-shell@aunetx"
           # ...
           # ...
Line 69: Line 119:
     };
     };
   };
   };
}
}|name=~/.config/home-manager/home.nix|lang=nix}}
</nowiki>}}


=== dconf settings ===
== Tips and tricks ==


Most of the GNOME settings are stored in [https://en.wikipedia.org/wiki/Dconf dconf] database. Settings are stored as keys placed in folders.
=== GNOME power user apps ===
Both GNOME Tweaks (accessible as <code>gnome-tweaks</code>) and [https://gitlab.gnome.org/TheEvilSkeleton/Refine Refine] (accessible as <code>refine</code>) allow you to change certain GNOME settings that are hidden by default (such as interface font, window decoration buttons like maximize/minimize, icon themes and GTK themes, etc).  


To learn about settings that can be configured with dconf either look into <code>dconf-editor</code> program (provided by <code>gnome.dconf-editor</code> package) or type <code>dconf watch /</code> in the terminal and change settings from the GUI and see which options are responsible for that component/element.
The GNOME shell extension [https://extensions.gnome.org/extension/3843/just-perfection/ Just Perfection] also allows for customizing nearly all parts of the GNOME shell interface.  


These settings can be changed by NixOS via <code>programs.dconf</code> module or by [[Home Manager]] via <code>dconf</code> module. To so in Home Manager, you need to change <code>dconf.settings</code> attribute set. This attribute set contains absolute folder paths (without leading slash) as attributes' names which value is another attribute set with keys (settings).
=== GNOME Qt integration ===
 
Using the following example configuration, Qt applications will have a look similar to the adwaita style used by GNOME using a dark theme.
For example, to change the value of <code>clock-show-weekday</code> key that is located in <code>/org/gnome/desktop/interface</code>, you need to the following:
{{File|3={
 
   qt = {
{{file|~/.config/home-manager/home.nix|nix|<nowiki>
{
   dconf = {
     enable = true;
     enable = true;
 
     platformTheme = "gnome";
     settings = {
     style = "adwaita-dark";
      # You need quotes to escape '/'
      "org/gnome/desktop/interface" = {
        clock-show-weekday = true;
      };
     };
   };
   };
}
}|name=/etc/nixos/configuration.nix|lang=nix}}
</nowiki>}}
For other themes, you may need the packages <code>libsForQt5.qt5ct</code> and <code>libsForQt5.qtstyleplugin-kvantum</code> and a symlink from <code>~/.config/Kvantum/</code> to your theme package. Here is an example using Arc-Dark and [[Home Manager]]. In the Home Manager configuration:
 
{{File|3={
Same can be achieved by using system configuration.
   qt = {
 
{{file|/etc/nixos/configuration.nix|nix|<nowiki>
{
   programs.dconf = {
     enable = true;
     enable = true;
     profiles.user.databases = [
     platformTheme = "qtct";
      {
    style = "kvantum";
        lockAll = true; # prevents overriding
        settings = {
          "org/gnome/desktop/interface" = {
            clock-show-weekday = true;
          };
        };
      }
    ];
   };
   };
}
</nowiki>}}


{{Note|Since dconf have more data types than Nix language (for example, tuples), in some cases you'll need to convert Nix value to a GVariant value. You can achieve that by using function defined in <code>lib.gvariant</code>, they're documented [https://nixos.org/manual/nixpkgs/stable/#sec-functions-library-gvariant here].}}
  xdg.configFile = {
    "Kvantum/ArcDark".source = "${pkgs.arc-kde-theme}/share/Kvantum/ArcDark";
    "Kvantum/kvantum.kvconfig".text = "[General]\ntheme=ArcDark";
  };
}|name=~/.config/home-manager/home.nix|lang=nix}}
For more details, see [https://discourse.nixos.org/t/guide-to-installing-qt-theme/35523/2 this] forum post.{{Note|Qt integration with the adwaita style isn't perfect and your mileage may vary.}}


== Tips and tricks ==
=== Experimental settings ===
GNOME has a number of experimental settings for features not fully completed and thus hidden from the user. As of GNOME 48, these are the experimental features you may want to use:
{{File|3={
  programs.dconf.profiles.user.databases = [
    {
      settings = {
        "org/gnome/mutter" = {
          experimental-features = [
            "scale-monitor-framebuffer" # Enables fractional scaling (125% 150% 175%)
            "variable-refresh-rate" # Enables Variable Refresh Rate (VRR) on compatible displays
            "xwayland-native-scaling" # Scales Xwayland applications to look crisp on HiDPI screens
          ];
        };
      };
    }
  ];
}|name=/etc/nixos/configuration.nix|lang=nix}}


=== To run GNOME programs outside of GNOME ===
=== Discover dconf settings ===
If you wish to discover the corresponding dconf entry for a given setting in a program, you can run `dconf watch /` inside of a terminal and change the setting graphically. For example, when changing toggling the Quick-Settings option "Dark Style" from "on" to "off" and back to "on," this will be the output:<syntaxhighlight lang="shell-session">
$ dconf watch /
/org/gnome/desktop/interface/color-scheme
  'default'


GNOME platform-based applications are largely [https://nixos.org/nixpkgs/manual/#sec-language-gnome self-contained], but they still depend, for one reason or another, on some global configuration. The {{ic|gnome.nix}} module sets all the necessary options for you but if you are running customized set-up, you might need to replicate that yourself.
/org/gnome/desktop/interface/color-scheme
  'prefer-dark'
</syntaxhighlight>Otherwise you can use the gsettings programs to inspect the schemas installed on your system. For example, to inspect all the keys contained within <code>/org/gnome/desktop/background</code> you could run:<syntaxhighlight lang="shell-session">
$ gsettings list-keys org.gnome.desktop.background
color-shading-type
picture-opacity
picture-options
picture-uri
picture-uri-dark
primary-color
secondary-color
show-desktop-icons


For instance, if you see the following error:
</syntaxhighlight>Then to see the range of possible values for one of the keys such as <code>picture-options</code> you could then run:<syntaxhighlight lang="shell-session">
$ gsettings range org.gnome.desktop.background picture-options
enum
'none'
'wallpaper'
'centered'
'scaled'
'stretched'
'zoom'
'spanned'


<syntaxhighlight lang="text">
dconf-WARNING **: failed to commit changes to dconf: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name ca.desrt.dconf was not provided by any .service files
</syntaxhighlight>
you should enable dconf module:
<syntaxhighlight lang="nix">
{
  programs.dconf.enable = true;
}
</syntaxhighlight>If you're using the default theme, GTK-3 applications may not respect the dark theme if they can't find the Adwaita. To fix it, make sure you have the <code>gnome-themes-extra</code> package installed:<syntaxhighlight lang="nix">
{
  environment.systemPackages = [ pkgs.gnome-themes-extra ];
}
</syntaxhighlight>
=== Systray Icons ===
To get systray icons, install the related GNOME shell extension
<syntaxhighlight lang="nix">
{
  environment.systemPackages = [ pkgs.gnomeExtensions.appindicator ];
}
</syntaxhighlight>


And ensure gnome-settings-daemon udev rules are enabled:
</syntaxhighlight>Which tells you that the ''key'' <code>picture-options</code> located in ''schema'' <code>/org/gnome/desktop/background/</code> accepts a ''value'' of type enumeration (a single string value from a set of accepted values).


<syntaxhighlight lang="nix">
=== Enable system tray icons ===
{
GNOME does not currently support system tray icons. However, Ubuntu has created an [https://extensions.gnome.org/extension/615/appindicator-support/ extension] that implements this in the top bar. You can install this extension with the following in NixOS:
{{File|3={
  environment.systemPackages = [ pkgs.gnomeExtensions.appindicator  ];
   services.udev.packages = [ pkgs.gnome-settings-daemon ];
   services.udev.packages = [ pkgs.gnome-settings-daemon ];
}
}|name=/etc/nixos/configuration.nix|lang=nix}}
</syntaxhighlight>
 
=== To run old applications ===
 
Some old applications use GConf service to store configuration. This has been deprecated for many years but some applications were abandoned before they managed to upgrade to a newer dconf system. If you are running such application and getting an error like:
 
<syntaxhighlight lang="text">
GLib.GException: Failed to contact configuration server; the most common cause is a missing or misconfigured D-Bus session bus daemon. See http://projects.gnome.org/gconf/ for information
</syntaxhighlight>
 
you need to add {{ic|gnome2.GConf}} to the list of dbus packages in your {{ic|configuration.nix}}:
 
<syntaxhighlight lang="nix">
{
  services.dbus.packages = with pkgs; [ gnome2.GConf ];
}
</syntaxhighlight>
 
After applying the update restart your desktop session to refresh the user-specific dbus session.


=== Profiling (with sysprof) ===
=== Profiling (with sysprof) ===


Install {{ic|sysprof}} as a ''system'' package (it won't work properly if installed against users). Then enable the associated service with  
Install {{ic|sysprof}} as a ''system'' package (it won't work properly if installed against users). Then enable the associated service with


<syntaxhighlight lang="nix">
<syntaxhighlight lang="nix">
Line 206: Line 237:
</nowiki>}}
</nowiki>}}


== Troubleshoots ==
=== Excluding GNOME Applications ===
 
To exclude certain applications that are installed by default with GNOME, set the {{nixos:option|environment.gnome.excludePackages}} module option (Optional Packages: [https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/services/desktop-managers/gnome.nix#L449-L471 gnome.nix]):
 
{{file|/etc/nixos/configuration.nix|nix|<nowiki>
  environment.gnome.excludePackages = with pkgs; [
    totem
  ];
</nowiki>}}
 
== Troubleshooting ==
 
=== Missing cursor/cursor is a white box ===
This occurs when installing GNOME from an existing NixOS installation that used a different desktop environment that modified dconf (most likely switching from KDE to GNOME). To easily fix this: reset all dconf settings.<syntaxhighlight lang="bash">
$ dconf reset -f /
</syntaxhighlight>
 
=== Running GConf-based applications ===
 
There exist very old applications which use the deprecated GConf service to store configuration. If you are running such an application and are getting an error like:
 
<syntaxhighlight lang="text">
GLib.GException: Failed to contact configuration server; the most common cause is a missing or misconfigured D-Bus session bus daemon. See http://projects.gnome.org/gconf/ for information
</syntaxhighlight>
 
you will need to add <code>pkgs.gnome2.GConf</code> to the list of dbus packages in your NixOS configuration like so:
 
{{File|3={
  services.dbus.packages = with pkgs; [ gnome2.GConf ];
}|name=/etc/nixos/configuration.nix|lang=nix}}
 
After rebuilding your configuration, restart your desktop session to have GConf take effect.


=== Automatic login ===
=== Automatic login ===


If you have enabled [https://help.gnome.org/admin/system-admin-guide/stable/login-automatic.html.en auto login] (with <!-- [[GDM]] -->[[{{PAGENAME}}]]) with something like
As a potential workaround<ref>https://github.com/NixOS/nixpkgs/issues/103746#issuecomment-945091229</ref> for automatic login, include this in your NixOS configuration:
: <syntaxHighlight lang="console">
 
$ grep autoLogin /etc/nixos/configuration.nix
{{File|3={
</syntaxHighlight>
  services.xserver.displayManager.autoLogin.enable = true;
<syntaxHighlight lang="nix">
  services.xserver.displayManager.autoLogin.user = "account";
services.xserver.displayManager.autoLogin.enable = true;
 
services.xserver.displayManager.autoLogin.user = "account";
</syntaxHighlight>
than add the following (as a workaround for a current (2023)<ref>https://github.com/NixOS/nixpkgs/issues/103746#issuecomment-945091229</ref> problem)
: <syntaxHighlight lang="console"># nano /etc/nixos/configuration.nix</syntaxHighlight>
<syntaxHighlight lang="nix">
{
   systemd.services."getty@tty1".enable = false;
   systemd.services."getty@tty1".enable = false;
   systemd.services."autovt@tty1".enable = false;
   systemd.services."autovt@tty1".enable = false;
}
}|name=/etc/nixos/configuration.nix|lang=nix}}
</syntaxHighlight>
 
== See also ==
* [[GNOME/Calendar]]


=== GDM does not show user ===
The GDM (GNOME Display Manager) will not display a user if their default shell is not listed in <code>/etc/shells</code>. If your shell, such as zsh, is not included in <code>/etc/shells</code>, you need to add it to the configuration.{{File|3={
  environment.shells = with pkgs; [ zsh ];
}|name=/etc/nixos/configuration.nix|lang=nix}}
:
== References ==
[[Category:Desktop environment]]
[[Category:Desktop environment]]
[[Category:Applications]]
[[Category:Applications]]
[[Category:NixOS Manual]]
[[Category:NixOS Manual]]
[[Category:GNOME]]
[[Category:GNOME]]

Latest revision as of 02:32, 31 August 2025

GNOME (/(ɡ)noʊm/) is a desktop environment that seeks to be "an independent computing platform for everyone."[1]

This article is an extension of the documentation in the NixOS manual.

Installation

GNOME desktop

To use the GNOME desktop environment on NixOS, the following configuration options must be set:

❄︎ /etc/nixos/configuration.nix
{ config, pkgs, ... }:

{

  # Pre 25.11
  services.xserver.enable = true;
  services.xserver.displayManager.gdm.enable = true;
  services.xserver.desktopManager.gnome.enable = true;

  # As of 25.11
  services.displayManager.gdm.enable = true;
  services.desktopManager.gnome.enable = true;

  # To disable installing GNOME's suite of applications
  # and only be left with GNOME shell.
  services.gnome.core-apps.enable = false;
  services.gnome.core-developer-tools.enable = false;
  services.gnome.games.enable = false;
  environment.gnome.excludePackages = with pkgs; [ gnome-tour gnome-user-docs ];

}

Despite the options in NixOS versions before 25.11 being under the xserver module, GNOME uses Wayland by default. NixOS 25.11 and later removes support for the Xorg session entirely (though Xwayland is still included and supported for compatibility).

GNOME extensions

GNOME offers support for changing/overhauling the user interface (GNOME Shell) through the use of Extensions. Extensions are bundles of third-party GJS modules that are loaded while GNOME is running to augment the user experience. A repository of GNOME extensions can be found on GNOME's official webpage and can be installed imperatively if needed by unpacking the extension in ~/.local/share/gnome-shell/extensions directory. Extensions can only be activated if it supports the GNOME release that it's installed alongside with.

In addition, NixOS automatically packages all officially available GNOME extensions under the pkgs.gnomeExtensions attribute. Extensions which require additional dependencies are then manually packaged if needed. Installed extensions can be enabled graphically through the built-in "Extensions" application or through the gnome-extensions command line interface.

❄︎ /etc/nixos/configuration.nix
{
  environment.systemPackages = with pkgs; [
    gnomeExtensions.blur-my-shell
    gnomeExtensions.just-perfection
    gnomeExtensions.arc-menu
  ];
}

Configuration

dconf

Dconf is a low-level configuration system for storing and loading configurations. The dconf database is stored in a single binary file in ~/.config/dconf/user and contains all known configuration values for all applications and programs that use dconf (GNOME applications and shell, gtk, etc).

For example, the setting which controls the accent color of GNOME shell is located in the schema labeled /org/gnome/desktop/interface/ which contains the key accent-color which accepts a GVariant value of type enum (one of 'blue', 'teal', 'green', etc)

NixOS and Home Manager both provide an interface for declarative configuration of dconf settings exposed in programs.dconf and dconf modules respectively.

Going back to the previous example, to set the accent color of GNOME in a declarative manner in NixOS as well as mapping the keyboard's "caps lock" key to "ctrl" you would write:

❄︎ /etc/nixos/configuration.nix
{
  programs.dconf.profiles.user.databases = [
    {
      lockAll = true; # prevents overriding
      settings = {
        "org/gnome/desktop/interface" = {
          accent-color = "blue";
        };
        "org/gnome/desktop/input-sources" = {
          xkb-options = [ "ctrl:nocaps" ];
        };
      };
    }
  ];
}

And the equivalent snippet in Home Manager:

❄︎ ~/.config/home-manager/home.nix
{
  dconf.enable = true;
  dconf.settings = {
    "org/gnome/desktop/interface" = {
      accent-color = "blue";
    };
    "org/gnome/desktop/input-sources" = {
      xkb-options = [ "ctrl:nocaps" ];
    };
  };
}

Thus the settings attribute accepts an attribute set whose keys are schemas with each schema's value being a nested attribute set of the schema's keys with their appropriate GVariant value.

Note: Schemas in Nix are written without leading and trailing slashes. In addition, since dconf have more data types than the Nix language (for example, tuples), in some cases you'll need to convert Nix value to a GVariant value. You can achieve that by using the functions defined under lib.gvariant, they're documented here.

If you wish to revert all dconf settings back to their default state (reset GNOME essentially) then use the following command which resets all schemas directories available on your system, note that this will affect all programs that use dconf, including GNOME apps and extensions.

$ dconf reset -f /

Extensions

Extensions are not activated by default when installed with Nix but can be configured to do so using the respective dconf modules. The schema is /org/gnome/shell/ with the key enabled-extensions which accepts a list of strings that represent extension UUIDs. If the extension was installed with Nix, then the UUID can be accessed by the extensionUuid attribute of the extension itself. Each extension's configuration can then be found under their corresponding schema in /org/gnome/shell/extensions/ and be configured as needed.

For example, in Home Manager, you could write:

❄︎ ~/.config/home-manager/home.nix
{
  dconf = {
    enable = true;
    settings = {
      "org/gnome/shell" = {
        # disable-user-extensions = true; # Optionally disable user extensions entirely
        enabled-extensions = [
          # Put UUIDs of extensions that you want to enable here.
          # If the extension you want to enable is packaged in nixpkgs,
          # you can easily get its UUID by accessing its extensionUuid
          # field (look at the following example).
          pkgs.gnomeExtensions.gsconnect.extensionUuid

          # Alternatively, you can manually pass UUID as a string.
          "blur-my-shell@aunetx"
          # ...
        ];
      };

      # Configure individual extensions
      "org/gnome/shell/extensions/blur-my-shell" = {
        brightness = 0.75;
        noise-amount = 0;
      };
    };
  };
}

Tips and tricks

GNOME power user apps

Both GNOME Tweaks (accessible as gnome-tweaks) and Refine (accessible as refine) allow you to change certain GNOME settings that are hidden by default (such as interface font, window decoration buttons like maximize/minimize, icon themes and GTK themes, etc).

The GNOME shell extension Just Perfection also allows for customizing nearly all parts of the GNOME shell interface.

GNOME Qt integration

Using the following example configuration, Qt applications will have a look similar to the adwaita style used by GNOME using a dark theme.

❄︎ /etc/nixos/configuration.nix
{
  qt = {
    enable = true;
    platformTheme = "gnome";
    style = "adwaita-dark";
  };
}

For other themes, you may need the packages libsForQt5.qt5ct and libsForQt5.qtstyleplugin-kvantum and a symlink from ~/.config/Kvantum/ to your theme package. Here is an example using Arc-Dark and Home Manager. In the Home Manager configuration:

❄︎ ~/.config/home-manager/home.nix
{
  qt = {
    enable = true;
    platformTheme = "qtct";
    style = "kvantum";
  };

  xdg.configFile = {
    "Kvantum/ArcDark".source = "${pkgs.arc-kde-theme}/share/Kvantum/ArcDark";
    "Kvantum/kvantum.kvconfig".text = "[General]\ntheme=ArcDark";
  };
}

For more details, see this forum post.

Note: Qt integration with the adwaita style isn't perfect and your mileage may vary.

Experimental settings

GNOME has a number of experimental settings for features not fully completed and thus hidden from the user. As of GNOME 48, these are the experimental features you may want to use:

❄︎ /etc/nixos/configuration.nix
{
  programs.dconf.profiles.user.databases = [
    {
      settings = {
        "org/gnome/mutter" = {
          experimental-features = [
            "scale-monitor-framebuffer" # Enables fractional scaling (125% 150% 175%)
            "variable-refresh-rate" # Enables Variable Refresh Rate (VRR) on compatible displays
            "xwayland-native-scaling" # Scales Xwayland applications to look crisp on HiDPI screens
          ];
        };
      };
    }
  ];
}

Discover dconf settings

If you wish to discover the corresponding dconf entry for a given setting in a program, you can run `dconf watch /` inside of a terminal and change the setting graphically. For example, when changing toggling the Quick-Settings option "Dark Style" from "on" to "off" and back to "on," this will be the output:

$ dconf watch /
/org/gnome/desktop/interface/color-scheme
  'default'

/org/gnome/desktop/interface/color-scheme
  'prefer-dark'

Otherwise you can use the gsettings programs to inspect the schemas installed on your system. For example, to inspect all the keys contained within /org/gnome/desktop/background you could run:

$ gsettings list-keys org.gnome.desktop.background
color-shading-type
picture-opacity
picture-options
picture-uri
picture-uri-dark
primary-color
secondary-color
show-desktop-icons

Then to see the range of possible values for one of the keys such as picture-options you could then run:

$ gsettings range org.gnome.desktop.background picture-options
enum
'none'
'wallpaper'
'centered'
'scaled'
'stretched'
'zoom'
'spanned'

Which tells you that the key picture-options located in schema /org/gnome/desktop/background/ accepts a value of type enumeration (a single string value from a set of accepted values).

Enable system tray icons

GNOME does not currently support system tray icons. However, Ubuntu has created an extension that implements this in the top bar. You can install this extension with the following in NixOS:

❄︎ /etc/nixos/configuration.nix
{
  environment.systemPackages = [ pkgs.gnomeExtensions.appindicator  ];
  services.udev.packages = [ pkgs.gnome-settings-daemon ];
}

Profiling (with sysprof)

Install sysprof as a system package (it won't work properly if installed against users). Then enable the associated service with

  services.sysprof.enable = true;

Automatic screen rotation

  hardware.sensor.iio.enable = true;

Dark mode

Change default color theme for all GTK4 applications to dark using Home Manager.

❄︎ ~/.config/home-manager/home.nix
{
  dconf = {
    enable = true;
    settings."org/gnome/desktop/interface".color-scheme = "prefer-dark";
  };
}

Excluding GNOME Applications

To exclude certain applications that are installed by default with GNOME, set the environment.gnome.excludePackages module option (Optional Packages: gnome.nix):

❄︎ /etc/nixos/configuration.nix
  environment.gnome.excludePackages = with pkgs; [
    totem
  ];

Troubleshooting

Missing cursor/cursor is a white box

This occurs when installing GNOME from an existing NixOS installation that used a different desktop environment that modified dconf (most likely switching from KDE to GNOME). To easily fix this: reset all dconf settings.

$ dconf reset -f /

Running GConf-based applications

There exist very old applications which use the deprecated GConf service to store configuration. If you are running such an application and are getting an error like:

GLib.GException: Failed to contact configuration server; the most common cause is a missing or misconfigured D-Bus session bus daemon. See http://projects.gnome.org/gconf/ for information

you will need to add pkgs.gnome2.GConf to the list of dbus packages in your NixOS configuration like so:

❄︎ /etc/nixos/configuration.nix
{
  services.dbus.packages = with pkgs; [ gnome2.GConf ];
}

After rebuilding your configuration, restart your desktop session to have GConf take effect.

Automatic login

As a potential workaround[2] for automatic login, include this in your NixOS configuration:

❄︎ /etc/nixos/configuration.nix
{
  services.xserver.displayManager.autoLogin.enable = true;
  services.xserver.displayManager.autoLogin.user = "account";
  
  systemd.services."getty@tty1".enable = false;
  systemd.services."autovt@tty1".enable = false;
}

GDM does not show user

The GDM (GNOME Display Manager) will not display a user if their default shell is not listed in /etc/shells. If your shell, such as zsh, is not included in /etc/shells, you need to add it to the configuration.

❄︎ /etc/nixos/configuration.nix
{
  environment.shells = with pkgs; [ zsh ];
}

References