1. A method performed by a computing system, comprising: preserving a customized object while upgrading an enterprise application to an upgraded enterprise application, comprising merging a plurality of repositories into a merged repository, wherein the plurality of repositories comprises a customized repository, an original repository, and an upgraded repository, the customized repository comprises the customized object, the original repository comprises an original object, the customized object is produced by applying one or more customizations to the original object, and the upgraded repository comprises an upgraded object; identifying the customized object for preservation, wherein the customized object is preserved, while the enterprise application is upgraded, by retaining the customized object in the merged repository; and transforming the customized object, wherein the transforming enables the customized object to operate with the upgraded enterprise application without reapplying the one or more customizations, the transforming comprises determining a type of the customized object, performing a transformational function based on the type, identifying an updated method in the upgraded object, and replacing an original method call in the customized object with an updated method call, the replacing results in the customized object being configured to make a method call to the updated method instead of an original method, the original method call is a method call to the original method, and the updated method call is a method call to the updated method.