A content management system (CMS) receives a create request indicating portions of content items maintained in a repository. CMS generates a new content item incorporating the indicated portions and checks-in the new content item into the repository. In another aspect, a CMS stores a link data indicating that a first portion of the new content item is linked to a second portion of a content item existing in the repository. Upon determining that the second portion has been modified after the checking-in of the new content item, CMS replaces the first portion in the new content item with the modified portion. In one more aspect, CMS receives an update request specifying a modified portion of a content item. CMS generates a revised content item by incorporating the modified portion in the content item and checks-in the revised content item as a revised version of the content item into the repository.