7 files changed, 124 insertions, 23 deletions
diff --git a/nixos/modules/config/shells-environment.nix b/nixos/modules/config/shells-environment.nix
index b6dcb9aed4e7..555db459f57a 100644
--- a/nixos/modules/config/shells-environment.nix
+++ b/nixos/modules/config/shells-environment.nix
@@ -34,6 +34,7 @@ in
 
     environment.variables = mkOption {
       default = {};
+      example = { EDITOR = "nvim"; VISUAL = "nvim"; };
       description = ''
         A set of environment variables used in the global environment.
         These variables will be set on shell initialisation (e.g. in /etc/profile).
@@ -80,7 +81,7 @@ in
       default = "";
       description = ''
         Shell script code called during shell initialisation.
-        This code is asumed to be shell-independent, which means you should
+        This code is assumed to be shell-independent, which means you should
         stick to pure sh without sh word split.
       '';
       type = types.lines;
@@ -90,7 +91,7 @@ in
       default = "";
       description = ''
         Shell script code called during login shell initialisation.
-        This code is asumed to be shell-independent, which means you should
+        This code is assumed to be shell-independent, which means you should
         stick to pure sh without sh word split.
       '';
       type = types.lines;
@@ -100,7 +101,7 @@ in
       default = "";
       description = ''
         Shell script code called during interactive shell initialisation.
-        This code is asumed to be shell-independent, which means you should
+        This code is assumed to be shell-independent, which means you should
         stick to pure sh without sh word split.
       '';
       type = types.lines;
diff --git a/nixos/modules/config/system-path.nix b/nixos/modules/config/system-path.nix
index 361151665018..ffb437491f6c 100644
--- a/nixos/modules/config/system-path.nix
+++ b/nixos/modules/config/system-path.nix
@@ -81,6 +81,12 @@ in
         description = "List of additional package outputs to be symlinked into <filename>/run/current-system/sw</filename>.";
       };
 
+      extraSetup = mkOption {
+        type = types.lines;
+        default = "";
+        description = "Shell fragments to be run after the system environment has been created. This should only be used for things that need to modify the internals of the environment, e.g. generating MIME caches. The environment being built can be accessed at $out.";
+      };
+
     };
 
     system = {
@@ -107,12 +113,7 @@ in
         "/etc/gtk-3.0"
         "/lib" # FIXME: remove and update debug-info.nix
         "/sbin"
-        "/share/applications"
-        "/share/desktop-directories"
         "/share/emacs"
-        "/share/icons"
-        "/share/menus"
-        "/share/mime"
         "/share/nano"
         "/share/org"
         "/share/themes"
@@ -132,10 +133,6 @@ in
       # outputs TODO: note that the tools will often not be linked by default
       postBuild =
         ''
-          if [ -x $out/bin/update-mime-database -a -w $out/share/mime ]; then
-              XDG_DATA_DIRS=$out/share $out/bin/update-mime-database -V $out/share/mime > /dev/null
-          fi
-
           if [ -x $out/bin/gtk-update-icon-cache -a -f $out/share/icons/hicolor/index.theme ]; then
               $out/bin/gtk-update-icon-cache $out/share/icons/hicolor
           fi
@@ -143,17 +140,8 @@ in
           if [ -x $out/bin/glib-compile-schemas -a -w $out/share/glib-2.0/schemas ]; then
               $out/bin/glib-compile-schemas $out/share/glib-2.0/schemas
           fi
-
-          if [ -x $out/bin/update-desktop-database -a -w $out/share/applications ]; then
-              $out/bin/update-desktop-database $out/share/applications
-          fi
-
-          if [ -x $out/bin/install-info -a -w $out/share/info ]; then
-            shopt -s nullglob
-            for i in $out/share/info/*.info $out/share/info/*.info.gz; do
-                $out/bin/install-info $i $out/share/info/dir
-            done
-          fi
+          
+          ${config.environment.extraSetup}
         '';
     };
 
diff --git a/nixos/modules/config/users-groups.nix b/nixos/modules/config/users-groups.nix
index ddec21b5f6e5..426e1666a814 100644
--- a/nixos/modules/config/users-groups.nix
+++ b/nixos/modules/config/users-groups.nix
@@ -524,6 +524,8 @@ in {
       utmp.gid = ids.gids.utmp;
       adm.gid = ids.gids.adm;
       input.gid = ids.gids.input;
+      kvm.gid = ids.gids.kvm;
+      render.gid = ids.gids.render;
     };
 
     system.activationScripts.users = stringAfter [ "stdio" ]
diff --git a/nixos/modules/config/xdg/autostart.nix b/nixos/modules/config/xdg/autostart.nix
new file mode 100644
index 000000000000..0ee94fed818b
--- /dev/null
+++ b/nixos/modules/config/xdg/autostart.nix
@@ -0,0 +1,22 @@
+{ config, lib, ... }:
+
+with lib;
+{
+  options = {
+    xdg.autostart.enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = ''
+        Whether to install files to support the 
+        <link xlink:href="https://specifications.freedesktop.org/autostart-spec/autostart-spec-latest.html">XDG Autostart specification</link>.
+      '';
+    };
+  };
+
+  config = mkIf config.xdg.autostart.enable {
+    environment.pathsToLink = [ 
+      "/etc/xdg/autostart"
+    ];
+  };
+
+}
diff --git a/nixos/modules/config/xdg/icons.nix b/nixos/modules/config/xdg/icons.nix
new file mode 100644
index 000000000000..8268a3771a0e
--- /dev/null
+++ b/nixos/modules/config/xdg/icons.nix
@@ -0,0 +1,27 @@
+{ config, lib, ... }:
+
+with lib;
+{
+  options = {
+    xdg.icons.enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = ''
+        Whether to install files to support the 
+        <link xlink:href="https://specifications.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html">XDG Icon Theme specification</link>.
+      '';
+    };
+  };
+
+  config = mkIf config.xdg.icons.enable {
+    environment.pathsToLink = [ 
+      "/share/icons" 
+      "/share/pixmaps" 
+    ];
+    
+    environment.profileRelativeEnvVars = {
+      XCURSOR_PATH = [ "/share/icons" ];
+    };
+  };
+
+}
diff --git a/nixos/modules/config/xdg/menus.nix b/nixos/modules/config/xdg/menus.nix
new file mode 100644
index 000000000000..c172692df5d7
--- /dev/null
+++ b/nixos/modules/config/xdg/menus.nix
@@ -0,0 +1,25 @@
+{ config, lib, ... }:
+
+with lib;
+{
+  options = {
+    xdg.menus.enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = ''
+        Whether to install files to support the 
+        <link xlink:href="https://specifications.freedesktop.org/menu-spec/menu-spec-latest.html">XDG Desktop Menu specification</link>.
+      '';
+    };
+  };
+
+  config = mkIf config.xdg.menus.enable {
+    environment.pathsToLink = [ 
+      "/share/applications"
+      "/share/desktop-directories"
+      "/etc/xdg/menus"
+      "/etc/xdg/menus/applications-merged"
+    ];
+  };
+
+}
diff --git a/nixos/modules/config/xdg/mime.nix b/nixos/modules/config/xdg/mime.nix
new file mode 100644
index 000000000000..f1b672234a34
--- /dev/null
+++ b/nixos/modules/config/xdg/mime.nix
@@ -0,0 +1,36 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+{
+  options = {
+    xdg.mime.enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = ''
+        Whether to install files to support the 
+        <link xlink:href="https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-latest.html">XDG Shared MIME-info specification</link> and the
+        <link xlink:href="https://specifications.freedesktop.org/mime-apps-spec/mime-apps-spec-latest.html">XDG MIME Applications specification</link>.
+      '';
+    };
+  };
+
+  config = mkIf config.xdg.mime.enable {
+    environment.pathsToLink = [ "/share/mime" ];
+
+    environment.systemPackages = [ 
+      # this package also installs some useful data, as well as its utilities 
+      pkgs.shared-mime-info 
+    ];
+
+    environment.extraSetup = ''
+      if [ -w $out/share/mime ]; then
+        XDG_DATA_DIRS=$out/share ${pkgs.shared-mime-info}/bin/update-mime-database -V $out/share/mime > /dev/null
+      fi
+
+      if [ -w $out/share/applications ]; then
+        ${pkgs.desktop-file-utils}/bin/update-desktop-database $out/share/applications
+      fi
+    '';
+  };
+
+}