Four-language localization with branching email templates. Not just UI strings — validation messages, email subjects, email bodies, decline reasons, date and time formats all had to localize consistently across Croatian, English, German, and Italian. The decline templates for pickup orders and delivery orders are different, because the alternatives to suggest to the customer are different (if pickup is declined, suggest delivery; if delivery is declined, suggest pickup; if both are declined because of timing, give the phone number).