Shopify Checkout Extension & Custom Accounts
E-commerce · 2025

Shopify Checkout Extension & Custom Accounts

Production checkout extension for birthday collection with Klaviyo sync and a custom tiered rewards account page.

Client CAPULET GmbH E-commerce

Custom Shopify development for CAPULET, a German D2C jewelry brand. Built a Checkout UI Extension using the latest Shopify Checkout Extensions API (2025-07) that collects customer birthdays on the Thank You page and syncs them to Klaviyo for automated birthday marketing campaigns. Also developed a custom customer accounts page with a tiered loyalty rewards system powered by the LoyaltyLion API, Shopify metafields, and Shopify Flow automations.

The brand needed a way to collect customer birthdays post-purchase without disrupting the checkout flow, then automatically trigger birthday campaigns through Klaviyo. They also wanted a custom loyalty experience beyond LoyaltyLion's default widget — a branded account page showing tier status, rewards progress, and personalized benefits.

Built a Shopify Checkout UI Extension targeting purchase.thank-you.block.render with 12 merchant-configurable settings, automatic email detection via the useEmail() hook, and real-time Klaviyo profile sync through a custom backend. Created a custom Liquid customer accounts page that integrates the LoyaltyLion API to display tiered rewards, connects to Shopify metafields for personalized data, and uses Shopify Flow for automated tier progression.

Shopify
Checkout Extensions
Klaviyo
Liquid
LoyaltyLion
Production-deployed extension
Automated birthday campaigns
Custom tiered rewards system
Seamless Klaviyo + LoyaltyLion integration