1. A computer-implemented method for correlating artifacts between a versioned domain and an un-versioned domain, comprising: generating metadata having attributes of both of the versioned domain and the un-versioned domains, for an artifact in a set of artifacts, wherein the metadata is associated with the set of artifacts used in the versioned domain and the un-versioned domain; creating an instance of the artifact using a specific version of a versioned artifact definition for the artifact, wherein the instance comprises a first part directly created from the versioned artifact definition and a second part created from an un-versioned artifact definition for the artifact; specifying linkages between a respective representation of the artifact in the versioned domain and the un-versioned domain, wherein a specified linkage defines a relationship between multiple versions of an artifact in the versioned domain to a single un-versioned representation of a same artifact in the un-versioned domain; in response to providing a set of facades used to perform a selected one of author, execute and update instances of the artifact from either the versioned domain or the un-versioned domain, receiving the selected one of author, execute and update instances of the artifact from either the versioned domain or the un-versioned domain, wherein the selected one of author, execute and update instances of the artifact is performed using a set of predefined validation rules; and correlating all versions of the artifact definition to a single un-versioned definition, wherein the artifact definition of the single un-versioned definition is also correlated to all versions of the artifact definition, wherein in response to providing a set of facades used to perform a selected one of author, execute and update instances of the artifact further comprises: receiving a selection of one of a versioned facade and an un-versioned facade to update instance data; in response to receiving the selection of the versioned facade, accessing only those attributes defined on a specific version of the versioned definition and the set of predefined validation rules for attributes of that specific version of the versioned definition; validating updates on the versioned facade directly against the specific version of the versioned definition; in response to the updates being valid, corresponding attributes of the un-versioned facade are looked up and then saved in the same transaction to maintain synchronization between the versioned instances and the un-versioned instances of the definition; in response to receiving the selection of the un-versioned facade, exposing the attributes defined in all versions of the versioned definition as mapped to the corresponding attributes in the un-versioned definition; in response to changes made through the un-versioned facade, performing a lookup in the corresponding versioned facade, wherein the changes are mapped to that corresponding versioned facade, and corresponding validation rules in the set of predefined validation rules are checked, as defined by the specific versioned definition; in response to a successful update, saving the changes to the versioned instances as well as the un-versioned instances in a single transaction; and in response to a failure to update, rolling the changes back.