There are two ways that you could integrate with DOKU. You can either use our Checkout API or Direct API. Checkout API is an easier integration method as it does not require you to have your own checkout page; you can simply redirect to DOKU checkout page for your customers to make payment. Direct API is a more customizable integration method as you can have your customers make payment on your own checkout page that is shown on your website/domain.
You may check the demo of DOKU Checkout API and Direct API here.
DOKU also supports integration via e-Commerce platforms or plugins such as Magento, WordPress (WooCommerce), Shopify, PrestaShop, OpenCart, and many more.
Visit DOKU API Documentation to learn more.