Systems and methods provide for submission, verification, and validation of one or more code packages associated with provisioning logic for third-party applications. A user may request verification as a publisher and submit a code package for use with a third-party application within a resource provider environment. The code package may be tested and, upon passing, be published to a public repository for discovery and use by other users. The code package may form part of an extension that is integrated into a template that enables automated provisioning of resources and applications.