import { render, Checkbox, useApplyAttributeChange, } from '@shopify/checkout-ui-extensions-react'; // 1. Choose an extension point render('Checkout::Dynamic::Render', () => ( )); function Extension() { const applyAttributeChange = useApplyAttributeChange(); // 2. Render a UI return ( I would like to receive a free gift with my order ); // 3. Call API methods to modify the checkout async function onCheckboxChange(isChecked) { const result = await applyAttributeChange({ key: 'requestedFreeGift', type: 'updateAttribute', value: isChecked ? 'yes' : 'no', }); console.log( 'applyAttributeChange result', result, ); } }