{% include /apps/checkout/plus-merchants.md %}
You can use checkout components to build app extensions that feel at home in any checkout experience.
Checkout UI extensions provide UI components that a [rendering extension](./rendering.md) can use to build an interface. Shopify renders the UI natively, so it's performant, accessible, and works in all of checkout's supported browsers.
## Components as building blocks
Checkout components are designed to be flexible, enabling you to layer and mix them to create highly-customized app extensions that feel seamless within the checkout experience.
{% resource_card_container %}
{% resource_card
type: :library,
link: "https://www.figma.com/community/file/1121180079120732846",
title: "Figma UI kit"
%}
Prototype checkout UI extensions faster with Shopify's public Figma component library
{% endresource_card %}
{% endresource_card_container %}
## Merchant branding
Merchants can apply their own branding to checkout. Checkout brand settings are automatically applied to the UI components for building the extension.