diff --git a/config/shared.nix b/config/shared.nix
index 7ff887e..d751580 100644
--- a/config/shared.nix
+++ b/config/shared.nix
@@ -9,8 +9,8 @@
     ./lnbits.nix
   ];
 
-  # Set hostname (extract from domain, e.g., "4lpaca" from "4lpaca.io")
-  networking.hostName = builtins.head (pkgs.lib.splitString "." domain);
+  # Set hostname (replace dots with hyphens, e.g., "demo.ariege.io" → "demo-ariege-io")
+  networking.hostName = builtins.replaceStrings ["."] ["-"] domain;
 
   # System packages
   environment.systemPackages = with pkgs; [