diff --git a/git-auto-update.nix b/git-auto-update.nix
index 53da1d2..5581416 100644
--- a/git-auto-update.nix
+++ b/git-auto-update.nix
@@ -1,58 +1,74 @@
 { config, pkgs, ... }:
 
+let
+  gitUpdateScript = pkgs.writeShellScript "nix-git-auto-update" ''
+    set -euo pipefail
+
+    LOCAL_PATH="/var/lib/nixos-config"
+    REPO_URL="https://git.skarockoi.de/ska/nixos-production.git"
+
+    if [ ! -d "$LOCAL_PATH/.git" ]; then
+      mkdir -p "$LOCAL_PATH"
+      chmod 700 "$LOCAL_PATH"
+      ${pkgs.git}/bin/git clone "$REPO_URL" "$LOCAL_PATH"
+      exit 0
+    fi
+
+    cd "$LOCAL_PATH"
+
+    ${pkgs.git}/bin/git fetch origin
+
+    LOCAL_HEAD=$(${pkgs.git}/bin/git rev-parse HEAD)
+    REMOTE_HEAD=$(${pkgs.git}/bin/git rev-parse origin/main)
+
+    if [ "$LOCAL_HEAD" != "$REMOTE_HEAD" ]; then
+      ${pkgs.git}/bin/git reset --hard origin/main
+      ${pkgs.nixos-rebuild}/bin/nixos-rebuild boot \
+        -I nixos-config="$LOCAL_PATH/configuration.nix"
+    fi
+  '';
+in
 {
+  ##############################
+  # Git Auto Update Script
+  ##############################
+
   environment.etc."nix-git-auto-update.sh" = {
     mode = "0700";
-    text = ''
-      #!/run/current-system/sw/bin/bash
-      set -e
-
-      export PATH="/run/current-system/sw/bin:/nix/var/nix/profiles/default/bin"
-      export NIX_PATH="nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos"
-
-      LOCAL_PATH="/var/lib/nixos-config"
-      REPO_URL="https://git.skarockoi.de/ska/nixos-production.git"
-
-      if [ ! -d "$LOCAL_PATH/.git" ]; then
-        mkdir -p "$LOCAL_PATH"
-        chmod 700 "$LOCAL_PATH"
-        git clone "$REPO_URL" "$LOCAL_PATH"
-        exit 0
-      fi
-
-      cd "$LOCAL_PATH"
-
-      git fetch origin
-      LOCAL_HEAD=$(git rev-parse HEAD)
-      REMOTE_HEAD=$(git rev-parse origin/main)
-
-      if [ "$LOCAL_HEAD" != "$REMOTE_HEAD" ]; then
-        git reset --hard origin/main
-        nixos-rebuild boot -I nixos-config="$LOCAL_PATH/configuration.nix"
-      fi
-    '';
+    source = gitUpdateScript;
   };
 
+  ##############################
+  # systemd service
+  ##############################
+
   systemd.services.nix-git-auto-update = {
     description = "Automatically update NixOS from Git";
-    script = "/etc/nix-git-auto-update.sh";
+
+    wants = [ "network-online.target" ];
+    after  = [ "network-online.target" ];
+
     serviceConfig = {
       Type = "oneshot";
-      User = "root";
-      Group = "root";
+      ExecStart = "/etc/nix-git-auto-update.sh";
       TimeoutStartSec = "10min";
       Restart = "on-failure";
-      StandardOutput = "journal";
-      StandardError = "journal";
     };
   };
 
+  ##############################
+  # systemd timer
+  ##############################
+
   systemd.timers.nix-git-auto-update = {
     description = "Periodic NixOS Git update check";
+
     wantedBy = [ "timers.target" ];
+
     timerConfig = {
-      OnBootSec = "60s";
+      OnBootSec = "2min";
       OnUnitActiveSec = "5min";
+      Persistent = true;
     };
   };
 }
\ No newline at end of file