Microsoft SharePoint Foundation provides new members that make it possible for you to upgrade custom Features through versioning and declarative upgrade actions. As a result, you can perform the following kinds of modular upgrades in SharePoint Foundation:

• Define upgrade definitions for new Feature versions.

• Provision a list instance as part of a Feature upgrade.

• Remove different sets of files from a Feature, depending on the Feature instance version, by creating separate upgrade action sets for different versions.

• Apply settings to site collections where a particular Feature is activated.