Auto-upgrade: Abort on failure

options/auto-upgrade.nix

@@ -118,8 +118,7 @@ in
                     send_email=yes
                     email_subject="Upgrade failed (exit code $exit_code)"
                     email_body="The system upgrade started at $start_time has failed with exit code $exit_code."
-                fi
-
+                else
                     echo "→ Determining package differences." | tee -a "$output_file"
                     installed_packages()
                     {
@@ -174,6 +173,7 @@ in
                         ${nixos-rebuild} switch ${toString cfg.flags} 2>&1 | tee -a "$output_file" || exit_code=$?
                     fi
                     ''}
+                fi
 
                 upgrade_output="$(cat "$output_file")"
                 rm -f "$output_file"