diff --git a/modules/host-users.nix b/modules/host-users.nix
index 85233ea..99dd4f3 100644
--- a/modules/host-users.nix
+++ b/modules/host-users.nix
@@ -1,4 +1,9 @@
-{ username, hostname, ... }@args:
+{
+  pkgs,
+  username,
+  hostname,
+  ...
+}@args:
 #############################################################
 #
 #  Host & Users configuration
@@ -13,6 +18,7 @@
   users.users."${username}" = {
     home = "/Users/${username}";
     description = username;
+    shell = pkgs.zsh;
   };
 
   nix.settings.trusted-users = [ username ];
diff --git a/modules/system.nix b/modules/system.nix
index 836df1e..8d0e750 100644
--- a/modules/system.nix
+++ b/modules/system.nix
@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ pkgs, username, ... }:
 ###################################################################################
 #
 #  macOS's System configuration
@@ -12,6 +12,12 @@
 {
   system = {
     # activationScripts are executed every time you boot the system or run `nixos-rebuild` / `darwin-rebuild`.
+    activationScripts.setFileLimit.text = ''
+      ulimit -Sn 10240
+    '';
+    activationScripts.setZshAsShell.text = ''
+      dscl . -create /Users/${username} UserShell /run/current-system/sw/bin/zsh
+    '';
     activationScripts.postUserActivation.text = ''
       # activateSettings -u will reload the settings from the database and apply them to the current session,
       # so we do not need to logout and login again to make the changes take effect.