Extension, Addon, and Modules
Feature Extension AddOn Module Purpose Core logic building block Extend storefront UI without modifying it Bundle of related extensions Affects Backend, services, models, etc. Frontend (JSPs, controllers, resources) Full functionality area (B2B, Marketplace) Contains items.xml?Yes No Not directly (extensions inside do) Installed via localextensions.xmladdoninstall commandInstaller recipe Example commercefacades, mycustomcorepaymentaddon, chineseaddressaddonb2b_acc_plus, marketplace