Email-driven admin workflow. The owner runs the kitchen. They're not going to log into an admin panel every time an order comes in. The workflow had to be "open email, click CONFIRM or DECLINE, get back to work."
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).
Delivery zone validation before submission, not after. Biograd na Moru has specific delivery boundaries. The worst customer experience is "submit order → wait → decline email because you're out of zone." The validation had to happen at the address input, inline, before the customer submits.
Pickup time picker that respects kitchen reality. The pizzeria's prep time is a rolling window. Customers shouldn't be able to pick "in 5 minutes" (too fast for the kitchen) or "in 90 minutes" (too far out, the kitchen doesn't pre-plan that).
Zero-fee handover. The restaurant had to own everything on delivery — Supabase, Netlify, Resend credentials, domain, codebase. No vendor lock-in, no recurring fees beyond what the infrastructure itself costs.