diff --git a/hosts/algiz/default.nix b/hosts/algiz/default.nix
index c98298d..9c6577a 100644
--- a/hosts/algiz/default.nix
+++ b/hosts/algiz/default.nix
@@ -8,10 +8,10 @@
     restic
   ];
 
-  languages = {
-    nim = true;
-    python = true;
-  };
+  oizys.languages = [
+    "nim"
+    "python"
+  ];
 
   environment.systemPackages = with pkgs; [
     rclone
diff --git a/hosts/algiz/system.nix b/hosts/algiz/system.nix
index 304deb2..14bc6ad 100644
--- a/hosts/algiz/system.nix
+++ b/hosts/algiz/system.nix
@@ -1,5 +1,5 @@
-{mkRune, ...}: {
-  users.motd = mkRune {
+{lib, ...}: {
+  users.motd = lib.mkRune {
     number = "6";
     rune = "algiz";
   };
diff --git a/hosts/mannaz/default.nix b/hosts/mannaz/default.nix
index e8e0114..fb91413 100644
--- a/hosts/mannaz/default.nix
+++ b/hosts/mannaz/default.nix
@@ -4,7 +4,7 @@
   ];
 
   oizys.desktop.enable = true;
-  cli.enable = true;
+
   # Enable the X11 windowing system.
   services.xserver = {
     enable = true;
diff --git a/hosts/mannaz/system.nix b/hosts/mannaz/system.nix
index efb0942..540fd5a 100644
--- a/hosts/mannaz/system.nix
+++ b/hosts/mannaz/system.nix
@@ -1,10 +1,10 @@
 {
   config,
   pkgs,
-  mkRune,
+  lib,
   ...
 }: {
-  users.motd = mkRune {
+  users.motd = lib.mkRune {
     number = "2";
     rune = "mannaz";
   };
diff --git a/hosts/othalan/default.nix b/hosts/othalan/default.nix
index 53556b2..aff37ed 100644
--- a/hosts/othalan/default.nix
+++ b/hosts/othalan/default.nix
@@ -14,17 +14,15 @@
     desktop.enable = true;
     vpn.enable = true;
     languages = [
-    "misc"
-    "python"
-    "nim"
-    "tex"
-    "node"
-  ];
+      "misc"
+      "python"
+      "nim"
+      "tex"
+      "node"
+    ];
   };
   vivaldi.enable = true;
 
-  
-
   environment.systemPackages = with pkgs; [
     zk
     rclone
diff --git a/hosts/othalan/system.nix b/hosts/othalan/system.nix
index cb02732..2a7874c 100644
--- a/hosts/othalan/system.nix
+++ b/hosts/othalan/system.nix
@@ -1,6 +1,6 @@
 {
   pkgs,
-  mkRune,
+  lib,
   ...
 }: {
   networking.networkmanager.enable = true;
@@ -27,7 +27,7 @@
     pamixer
   ];
 
-  services.getty.greetingLine = mkRune {
+  services.getty.greetingLine = lib.mkRune {
     rune = "othalan";
     runeKind = "ascii";
   };
diff --git a/lib/default.nix b/lib/default.nix
index dc042d4..02bbb6c 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -7,11 +7,9 @@
   inherit (nixpkgs.lib) hasSuffix nixosSystem genAttrs;
   inherit (nixpkgs.lib.filesystem) listFilesRecursive;
 
-  #supportedSystems = ["x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin"];
-  supportedSystems = ["x86_64-linux" ];
   runes = import ../modules/runes;
-in rec {
-  forAllSystems = f: genAttrs supportedSystems (system: f nixpkgs.legacyPackages.${system});
+  lib = nixpkgs.lib.extend (final: prev: {
+    mkIfIn = name: list: prev.mkIf (builtins.elem name list);
   mkRune = {
     rune,
     number ? "6",
@@ -19,6 +17,20 @@ in rec {
   }:
     "[1;3${number}m\n" + runes.${rune}.${runeKind} + "\n";
 
+
+  });
+
+  #supportedSystems = ["x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin"];
+  supportedSystems = ["x86_64-linux"];
+in rec {
+  forAllSystems = f: genAttrs supportedSystems (system: f nixpkgs.legacyPackages.${system});
+  # mkRune = {
+  #   rune,
+  #   number ? "6",
+  #   runeKind ? "braille",
+  # }:
+  #   "[1;3${number}m\n" + runes.${rune}.${runeKind} + "\n";
+  
   isNixFile = path: hasSuffix ".nix" path;
   buildOizys = _:
     forAllSystems (
@@ -42,7 +54,7 @@ in rec {
         isNixFile
         (listFilesRecursive (../. + "/hosts/${hostname}"));
 
-      specialArgs = {inherit inputs mkRune self;};
+      specialArgs = {inherit inputs lib self;};
     };
   mapHosts = dir: mapAttrs (name: _: mkSystem name) (readDir dir);
   buildHosts = _: mapHosts ../hosts;
diff --git a/modules/languages/misc.nix b/modules/languages/misc.nix
index 3472f93..e2cf5d4 100644
--- a/modules/languages/misc.nix
+++ b/modules/languages/misc.nix
@@ -4,10 +4,10 @@
   pkgs,
   ...
 }: let
-  inherit (lib) mkIf;
+  inherit (lib) mkIfIn;
   cfg = config.oizys.languages;
 in {
-  config = mkIf (builtins.elem "misc" cfg) {
+  config = mkIfIn "misc" cfg {
     environment.systemPackages = with pkgs; [
       go
       rustup
diff --git a/modules/languages/nim.nix b/modules/languages/nim.nix
index f4844d6..2aaebd1 100644
--- a/modules/languages/nim.nix
+++ b/modules/languages/nim.nix
@@ -4,10 +4,10 @@
   pkgs,
   ...
 }: let
-  inherit (lib) mkIf;
+  inherit (lib) mkIfIn;
   cfg = config.oizys.languages;
 in {
-  config = mkIf (builtins.elem "nim" cfg) {
+  config = mkIfIn "nim" cfg {
     environment.systemPackages = with pkgs; [
       nim
 
diff --git a/modules/languages/node.nix b/modules/languages/node.nix
index d1c2f1b..ac7ea30 100644
--- a/modules/languages/node.nix
+++ b/modules/languages/node.nix
@@ -4,10 +4,10 @@
   pkgs,
   ...
 }: let
-  inherit (lib) mkIf;
+  inherit (lib) mkIfIn;
   cfg = config.oizys.languages;
 in {
-  config = mkIf (builtins.elem "node" cfg) {
+  config = mkIfIn "node" cfg {
     environment.systemPackages = with pkgs; [
       nodejs
       nodePackages.pnpm
diff --git a/modules/languages/python.nix b/modules/languages/python.nix
index d15a626..9f53115 100644
--- a/modules/languages/python.nix
+++ b/modules/languages/python.nix
@@ -4,10 +4,11 @@
   pkgs,
   ...
 }: let
-  inherit (lib) mkIf;
+
+  inherit (lib) mkIfIn;
   cfg = config.oizys.languages;
 in {
-  config = mkIf (builtins.elem "python" cfg) {
+  config = mkIfIn "python" cfg {
     environment.systemPackages = let
       python = pkgs.python3.withPackages (ps: with ps; [pip]);
     in
diff --git a/modules/languages/tex.nix b/modules/languages/tex.nix
index 3bf95a5..a05d87a 100644
--- a/modules/languages/tex.nix
+++ b/modules/languages/tex.nix
@@ -4,11 +4,10 @@
   pkgs,
   ...
 }: let
-  inherit (lib) mkIf;
-  # cfg = config.oizys.languages;
-  langEnabled = name: builtins.elem name config.oizys.languages;
+  inherit (lib) mkIf mkIfIn;
+  cfg = config.oizys.languages;
 in {
-  config = mkIf (langEnabled "tex") {
+  config = mkIfIn "tex" cfg {
     environment.systemPackages = with pkgs; [
       texlive.combined.scheme-full
     ];