Upcart V2.0 migration guide

This article is a migration guide for upgrading from Upcart V1.0 to V2.0 modules. It covers breaking changes, CSS class mappings, JavaScript selector updates, troubleshooting, and the step-by-step migration process.

Overview

Upcart V2.0 modules introduce a complete architectural redesign of the cart system. The update focuses on improved performance, enhanced customization, and better maintainability.

This guide will help you understand what changes when migrating from V1.0 to V2.0 modules, what compatibility issues you may encounter, and how to update your existing customizations safely.

---

Breaking changes - CSS classname changes

V1 Classes (Deprecated)

🚨 The following V1.0 class names are no longer supported in V2.0:

.styles_Header__  
.styles_CartPreview__card__  
.styles_ProductRow__  
.styles_RewardsModule__  
...

/*******************  
*** Cart Header ***  
*******************/  
'upcart-header',  
'upcart-header-text',  
'upcart-header-logo',  
'upcart-header-close-button',  
'upcart-header-close-button-icon',  
  
/******************  
*** Line Items ***  
******************/  
'upcart-products-section',  
'upcart-product-item',  
/** > Title */  
'upcart-product-title',  
'upcart-product-title-link',  
/** > Prices */  
'upcart-item-prices-row',  
'upcart-item-price',  
'upcart-item-compare-price',  
'upcart-product-savings',  
/** > Options/Variants */  
'upcart-item-option',  
'upcart-item-option-category',  
'upcart-item-option-value',  
/** > Bundle Item Components */  
'upcart-bundle-item-image-wrapper',  
'upcart-bundle-item-product-title',  
'upcart-bundle-item-variant-title',  
'upcart-bundle-detail-toggle',  
/** > Properties */  
'upcart-item-properties',  
'upcart-item-property',  
'upcart-item-property-subscription',  
/** > Quantity Selector */  
'upcart-product-quantity-input',  
'upcart-product-quantity-minus',  
'upcart-product-quantity-plus',  
/** > Image */  
'upcart-product-image-wrapper',  
  
/*********************  
*** Announcements ***  
*********************/  
'upcart-announcement',  
  
/***************  
*** Rewards ***  
***************/  
'upcart-rewards',  
'upcart-rewards-message',  
'upcart-rewards-bar-background',  
'upcart-rewards-bar-foreground',  
'upcart-rewards-tier',  
'upcart-rewards-tier-circle',  
'upcart-rewards-tier-icon',  
'upcart-rewards-tier-description',  
  
/***************  
*** Upsells & Recommendations ***  
***************/  
'upcart-upsells-module',  
'upcart-upsells-title',  
'upcart-upsells-button',  
'upcart-upsell-item-title',  
'upcart-upsell-item-card',  
'upcart-upsell-item-image-wrapper',  
'upcart-upsell-item-image',  
'upcart-upsell-item-price',  
'upcart-upsell-item-price-row',  
'upcart-upsell-item-compare-price',  
'upcart-upsell-item-variant-selector',  
'upcart-upsells', // deprecated  
'upcart-recommendation-module',  
'upcart-recommendations-title',  
'upcart-recommendations-shop-now-button',  
  
/***************  
*** Add-ons ***  
***************/  
'upcart-addons',  
'upcart-addons-title',  
'upcart-addons-product-description',  
'upcart-addons-price',  
'upcart-addons-compare-price',  
'upcart-addons-toggle',  
'upcart-addons-image-wrapper',  
  
/**********************  
*** Discount Codes ***  
**********************/  
'upcart-discount-code-row',  
'upcart-discount-code-module',  
'upcart-discount-code-button',  
'upcart-discount-code-input',  
'upcart-discount-code-badge',  
'upcart-discount-code-icon',  
'upcart-discount-code-text',  
'upcart-discount-code-input-wrapper',  
  
/*****************************  
*** Subscription Upgrades ***  
*****************************/  
'upcart-subscription-upgrade-section',  
'upcart-subscription-upgrade-button',  
'upcart-subscription-upgrade-dropdown',  
  
/***************************  
*** Express Pay Buttons ***  
***************************/  
'upcart-express-pay-buttons-container',  
'upcart-express-pay-buttons-row',  
'upcart-express-pay-button',  
'upcart-express-pay-button-shop-pay',  
'upcart-express-pay-button-google-pay',  
'upcart-express-pay-button-paypal',  
'upcart-express-pay-button-apple-pay',  
'upcart-express-pay-button-amazon-pay',  
'upcart-express-pay-button-meta-pay',  
  
/********************  
*** Trust Badges ***  
********************/  
'upcart-trust-badge',  
'upcart-trust-badge-image',  
  
/****************************  
*** Out of Stock Warning ***  
****************************/  
'upcart-quantity-warning',  
'upcart-quantity-warning-text',  
  
/********************  
*** Integrations ***  
********************/  
'upcart-integration-zapiet-pickup',  
  
/*****************  
*** Skeletons ***  
*****************/  
'upcart-skeleton',  
'upcart-product-item-skeleton',  
'upcart-product-image-skeleton',  
'upcart-product-title-skeleton',  
'upcart-item-option-skeleton',  
'upcart-product-quantity-skeleton',  
'upcart-product-price-container-skeleton',  
'upcart-announcement-skeleton',  
'upcart-rewards-skeleton',  
'upcart-rewards-message-skeleton',  
'upcart-rewards-bar-skeleton',  
'upcart-upsells-module-skeleton',  
'upcart-upsells-title-skeleton',  
'upcart-upsell-item-image-skeleton',  
'upcart-upsell-item-title-skeleton',  
'upcart-upsell-item-price-skeleton',  
'upcart-upsells-button-skeleton',  
'upcart-trust-badge-skeleton',  
'upcart-trust-badge-image-skeleton',  
'upcart-checkout-button-container-skeleton',  
'upcart-checkout-button-skeleton',  
'upcart-addons-skeleton',  
'upcart-addons-image-wrapper-skeleton',  
'upcart-addons-skeleton-text-container',  
'upcart-discount-code-module-skeleton',  
'upcart-discount-code-input-skeleton',  
'upcart-discount-code-button-skeleton',  
'upcart-express-pay-buttons-container-skeleton',  
'upcart-express-pay-button-skeleton'

V2.0 classes (new system)

V2.0 introduces a structured naming system with internal and public class prefixes.

Internal classnames

These are reserved for internal use and may change without notice.

If you override these classes, future compatibility is not guaranteed.

/* Internal classes - for Upcart's internal styling */   
.upcart-internal-header  
.upcart-internal-header__close-button  
.upcart-internal-cart-items  
.upcart-internal-rewards  
...

Public classnames

🚨 Public classnames available list

/*******************  
***** Skeleton *****  
*******************/  
'upcart-public-skeleton'  
  
/*******************  
****** Header ******  
*******************/  
'upcart-public-header'  
'upcart-public-header__close-button'  
'upcart-public-header__close-button-icon'  
  
/*******************  
*** Announcement ***  
*******************/  
'upcart-public-announcement'  
  
/*******************  
** Recommendation **  
****** Upsell ******  
*******************/  
'upcart-public-component-upsell-tile'  
'upcart-public-component-upsell-tile__image-container'  
'upcart-public-component-upsell-tile__image'  
'upcart-public-component-upsell-tile__info'  
'upcart-public-component-upsell-tile__title-link'  
'upcart-public-component-upsell-tile__title'  
'upcart-public-component-upsell-tile__rating-row'  
'upcart-public-component-upsell-tile__stars'  
'upcart-public-component-upsell-tile__star--partial'  
'upcart-public-component-upsell-tile__reviews'  
'upcart-public-component-upsell-tile__price-row'  
'upcart-public-component-upsell-tile__price-compare-at'  
'upcart-public-component-upsell-tile__price'  
'upcart-public-component-upsell-tile__variant-row'  
'upcart-public-component__button'  
'upcart-public-component-loader'  
'upcart-public-upsell__skeleton'  
'upcart-public-upsell__skeleton-title'  
'upcart-public-upsell__skeleton-image'  
'upcart-public-upsell__skeleton-product-title'  
'upcart-public-upsell__skeleton-product-price'  
  
/*******************  
****** Notes *******  
*******************/  
'upcart-public-notes'  
'upcart-public-component-collapse__dropdown-container'  
'upcart-public-component-collapse__expand-icon'  
'upcart-public-notes__text-container'  
'upcart-public-notes__textarea'  
  
/*******************  
** Discount Code ***  
*******************/  
'upcart-public-discount-code'  
'upcart-public-discount-code__form'  
'upcart-public-discount-code__input-wrapper'  
'upcart-public-discount-code__input'  
'upcart-public-discount-code__suffix'  
'upcart-public-discount-code__error'  
'upcart-public-discount-code__button'  
'upcart-public-component__button'  
'upcart-public-skeleton'  
'upcart-public-discount-code__skeleton'  
'upcart-public-discount-code__skeleton-input'  
'upcart-public-discount-code__skeleton-button'  
  
/*******************  
** Trust Badges ****  
*******************/  
'upcart-public-trust-badges'  
'upcart-public-trust-badges__image'  
  
/*******************  
** Tiered Rewards **  
*******************/  
'upcart-public-rewards'  
'upcart-public-rewards__message'  
'upcart-public-rewards__bar'  
'upcart-public-component-segmented-progress-bar'  
'upcart-public-component-segmented-progress-bar__segments-container'  
'upcart-public-component-segmented-progress-bar__segment'  
'upcart-public-component-segmented-progress-bar__segment-fill'  
'upcart-public-component-segmented-progress-bar__segment-label'  
'upcart-public-component-segmented-progress-bar__milestone'  
'upcart-public-component-segmented-progress-bar__milestone--bottom'  
'upcart-public-component-segmented-progress-bar__milestone--top'  
'upcart-public-component-segmented-progress-bar__milestone--middle'  
'upcart-public-component-segmented-progress-bar__milestone-icon'  
'upcart-public-component-segmented-progress-bar__milestone-label'  
'upcart-public-component-segmented-progress-bar__milestone-label--align-right'  
'upcart-public-component-segmented-progress-bar__milestone-label--align-center'  
'upcart-public-rewards__skeleton',  
'upcart-public-rewards__skeleton-message',  
'upcart-public-rewards__skeleton-bar',  
  
/*******************  
**** Cart Items ****  
*******************/  
'upcart-public-component-product-tile'  
'upcart-public-component-product-tile__content'  
'upcart-public-component-product-tile__image-wrapper'  
'upcart-public-component-product-tile__image'  
'upcart-public-component-product-tile__info'  
'upcart-public-component-product-tile__header'  
'upcart-public-component-product-tile__product-title'  
'upcart-public-component-product-tile__title-link'  
'upcart-public-component-product-tile__remove-button'  
'upcart-public-component-loader'  
'upcart-public-component-product-tile__variant'  
'upcart-public-component-product-tile__properties'  
'upcart-public-component-product-tile__bundle'  
'upcart-public-component-product-tile__product-pricing'  
'upcart-public-component-product-tile__price-compare-at'  
'upcart-public-component-product-tile__price'  
'upcart-public-component-product-tile__savings'  
'upcart-public-component-product-tile__controls'  
'upcart-public-component-product-tile__quantity-selector'  
'upcart-public-component-product-tile__quantity-minus'  
'upcart-public-component-product-tile__quantity-plus'  
'upcart-public-component-product-tile__discount-codes'  
'upcart-public-component-tag'  
'upcart-public-component-tag__icon'  
'upcart-public-component-tag__text'  
'upcart-public-component-product-tile__subscription-upgrade'  
'upcart-public-component__button'  
'upcart-public-component-product-tile__select-wrapper'  
'upcart-public-component-product-tile__select'  
'upcart-public-product-properties__subscription'  
'upcart-public-product-properties__item'  
'upcart-public-product-properties__link'  
'upcart-public-cart-items__key-value-pair'  
'upcart-public-bundle-properties'  
'upcart-public-bundle-properties__variant-title'  
'upcart-public-component-collapse__dropdown-container'  
'upcart-public-bundle-properties__header'  
'upcart-public-component-collapse__expand-icon'  
'upcart-public-notes__text-container'  
'upcart-public-bundle-properties__item-components'  
'upcart-public-bundle-properties__item-component-row'  
'upcart-public-bundle-properties__image-wrapper'  
'upcart-public-bundle-properties__content'  
'upcart-public-bundle-properties__product-title'  
'upcart-public-upsell__skeleton'  
'upcart-public-upsell__skeleton-title'  
'upcart-public-upsell__skeleton-image'  
'upcart-public-upsell__skeleton-product-title'  
'upcart-public-upsell__skeleton-product-price'  
  
/*******************  
****** Notes *******  
*******************/  
'upcart-public-addons'  
'upcart-public-addons__image-wrapper'  
'upcart-public-addons__content-wrapper'  
'upcart-public-addons__content-title-wrapper'  
'upcart-public-addons__content-title'  
'upcart-public-addons__content-price'  
'upcart-public-addons__compare-at-price'  
'upcart-public-addons__price'  
'upcart-public-addons__content-description'  
'upcart-public-addons__toggle-wrapper'  
'upcart-public-addons__toggle'  
'upcart-public-addons__toggle-switch'  
'upcart-public-addons__toggle-slider'  
'upcart-public-skeleton'  
'upcart-public-addons__skeleton'  
'upcart-public-addons__skeleton-image'  
'upcart-public-addons__skeleton-text'  
  
/*******************  
*** Cart summary ***  
*******************/  
'upcart-public-cart-summary'  
'upcart-public-cart-summary__discount-codes'  
'upcart-public-cart-summary__discount-label'  
'upcart-public-cart-summary__slide-codes'  
'upcart-public-cart-summary__total-discount'

These are part of the public styling API (upcart-public-) and are safe to override for custom designs.

.upcart-public-header  
.upcart-public-header__close-button  
.upcart-public-rewards  
...

✅ DO’s

Use only upcart-public- class names for styling.

/* ✅ Correct usage */  
.upcart-public-header {     
  font-size: 18px;  
  font-weight: bold;   
}

❌ DON’T’s

Avoid override internal classnames

/* ❌ Avoid this */  
.upcart-internal-header {     
  font-size: 18px;  
  font-weight: bold;   
}

Avoid targeting specific nodes with deep or custom selectors.

/* ❌ Avoid this */  
.upcart-public-upsell div a {     
  font-size: 18px;  
  font-weight: bold;   
}

---

Data attribute system

V2.0 introduces a structured data attribute system for improved targeting and advanced customization.

<!-- V2 data attributes for targeting -->   
<div data-upcart-chunk="header-title-content" />     
<div data-internal-properties="hasNonDefaultAlignment=true" />       
<div data-placement="topOfFooter" />

These attributes make it easier to create flexible, data-driven templates while maintaining code clarity.

---

Template variable changes

V2 modules use a new template variable syntax with double curly braces #{{ }}.

Announcement Module

• V1.0: {TIMER}
• V2.0: #{{timer}}

Tiered Rewards Module

• V1.0: {AMOUNT} → V2: #{{amount}}
• V1.0: {COUNT} → V2: #{{count}}

---

Migration process

1. Backup Current Configuration

Before making any changes, back up your existing custom CSS and HTML files.

2. Test in Sandbox Mode

Set up your updated cart using sandbox mode to safely test new modules before going live.

---

Advanced customization with V2.0

Custom templates

V2.0 modules support fully custom templates for merchants who want complete control over layout and structure.

To enable custom templates:

1. Go to Settings > Cart settings > Access custom templates.
2. Enable the feature toggle.
3. Reference Upcart’s developer documentation for syntax and examples.

Note: Upcart’s support team cannot assist with developing, debugging, or troubleshooting custom templates.

---

Best Practices

• Always test updates in sandbox mode first.
• Migrate and update customizations incrementally.
• Use public classes for styling instead of internal ones.
• Keep backups of all previous versions before updating live settings.

---

Future Considerations

• V2 modules will continue to receive new features, optimizations, and updates.
• V1 modules are now in maintenance mode with limited support and no new features.
• Merchants are encouraged to migrate to V2 as soon as possible for full compatibility.