diff --git a/common/concentration.nix b/common/concentration.nix
new file mode 100644
index 0000000..83e2523
--- /dev/null
+++ b/common/concentration.nix
@@ -0,0 +1,11 @@
+{ pkgs, lib, config, ... }: {
+
+  networking.extraHosts =
+  ''
+    0.0.0.0   youtube.com
+    ::0       youtube.com
+
+    0.0.0.0   www.youtube.com
+    ::0       www.youtube.com
+  '';
+}
diff --git a/hosts/tartarus/configuration.nix b/hosts/tartarus/configuration.nix
index ac4d9fd..a122abe 100644
--- a/hosts/tartarus/configuration.nix
+++ b/hosts/tartarus/configuration.nix
@@ -14,6 +14,7 @@
     ../../common/arduino.nix
     ../../common/firefox.nix
     ../../common/common-packages.nix
+    ../../common/concentration.nix
   ];
 
   # stylix.enable = true;
@@ -45,15 +46,6 @@
   networking.networkmanager.enable = true;
 
 
-  networking.extraHosts =
-  ''
-    0.0.0.0   youtube.com
-    ::0       youtube.com
-
-    0.0.0.0   www.youtube.com
-    ::0       www.youtube.com
-  '';
-
   # Enable the X11 windowing system.
   # You can disable this if you're only using the Wayland session.
   services.xserver.enable = true;
diff --git a/hosts/ymir/configuration.nix b/hosts/ymir/configuration.nix
index 1d1e279..595fa3d 100644
--- a/hosts/ymir/configuration.nix
+++ b/hosts/ymir/configuration.nix
@@ -14,6 +14,7 @@
     ../../common/arduino.nix
     ../../common/firefox.nix
     ../../common/common-packages.nix
+    ../../common/concentration.nix
   ];
 
   # Bootloader.