Going headless means decoupling the frontend and backend of your ecommerce site. Thus, you use an ecommerce platform to power your commerce engine and a separate solution for the display layer.
Creating a headless build is possible with both BigCommerce and Shopify; however, it’s easier to do on BigCommerce. This is because BigCommerce has invested heavily in headless technology. Over 90% of the platform is exposed via APIs (the connections between frontend and backend that make headless possible). BigCommerce also has pre-built integrations with popular front ends including WordPress, Drupal and Adobe Experience Manager. The BigCommerce Channel Toolkit also makes it easier for developers to build custom frontend solutions to be used with BigCommerce on the backend.
Shopify also has a headless commerce offering, however rigid API calls per second limits hamper the potential to go headless on the platform. Shopify isn’t investing in headless in-house; the platform doesn’t have pre-built integrations with Adobe Experience Manager, Acquia, Drupal or Sitecore. The platform requires a third party to integrate with WordPress.