diff --git a/backup.nix b/backup.nix
index 2a35a09..135a942 100644
--- a/backup.nix
+++ b/backup.nix
@@ -29,7 +29,7 @@ let
 
       to="admin@heartles.xyz"
 
-      sendmail -f $from $to <<EOEMAIL
+      sendmail -f "$from" "$to" <<EOEMAIL
       To: $to
       From: $from
       Subject: $subject