diff --git a/options/auto-upgrade.nix b/options/auto-upgrade.nix
index 6d59d18..951b929 100644
--- a/options/auto-upgrade.nix
+++ b/options/auto-upgrade.nix
@@ -167,7 +167,7 @@ in
                 upgrade_output="$(cat "$output_file")"
                 rm -f "$output_file"
 
-                possible_warnings="$(${grep} -e "^trace:" <<<"$upgrade_output" || true)"
+                possible_warnings="$(${grep} -e "^\(warning\|trace\):" <<<"$upgrade_output" || true)"
                 if [ "$possible_warnings" != "" ] ; then
                     send_email=yes
                     email_subject_additions="$email_subject_additions with warnings"