Integration extensions
Windows Integration Server (WIS) overrides
Optimizely has a set of processes to check for changes in method signatures and constructors that are in the public surface area and call those out for documentation if we have to make changes - these are considered "breaking changes" and we document them. In Cloud, if the custom code references something in the private surface area, it will not be allowed in the environment and will fail our deployment checks.
Custom PDF implementation
A customer would like to generate a PDF that represents the current items in the cart, as this functionality is not in the base platform. A customer would like to create a PDF that shows the top ten most purchased products for a given category.
Override payment gateway settings
You can use extensions to override payment gateway settings. This allows you to define multiple payment gateways per site and multiple MIDs for the same gateway.