Inlinex DDU Discount App

The Inlinex DDU Discount App is a custom Shopify app built to solve the complexity of international duty pricing for an e-commerce skate shop. It implements a full OAuth flow to authenticate with Shopify stores and deploys a Shopify Function that dynamically applies percentage-based discounts depending on the customer's country. The discount rates are calibrated per market — 13% for APAC countries, 28% for the EU, 49% for India, 21% for Mexico/Korea/Thailand, and a 19% default for all other international markets. On the storefront, a custom Liquid snippet presents customers with a clean toggle between Postpay (DDU, export price) and Prepay (DDP, all duties included), with real-time price recalculation. Countries like Singapore, Hong Kong, the US, and Australia are excluded entirely. The cart page was redesigned with a mobile-first card layout for a clean, modern checkout experience. The app is deployed on Railway and the Shopify Function runs natively on Shopify's infrastructure for sub-millisecond discount evaluation.