Sana's Contracts
Sana Extension Framework has been developed to give developers a more structured way to extend Sana without introducing changes that can break compatibility and thus create issues during upgrades. With Extension Framework it is possible to create isolated extensions which do not break any existing code or existing dependencies and thus can be independent from future upgrades.
Sana provides full backward compatibility for extension-based add-ons, which means that when a webstore is upgraded to a newer version of Sana Commerce Cloud, all previously developed and installed extension-based add-ons will continue working correctly.