Application created by instantiating application templates sometimes use Nexus repository (if we speak about maven based applications). Build of such application could someone take a long time because of performance of originate Nexus repo. If user has own Nexus mirror, he/she can provide environment variable MAVEN_MIRROR_URL to build sourceStrategy to use private Nexus repo. By default application templates do not have this env. var. It would be nice to have specified this env. var here with reference to template parameter with non-required empty value by default. If user then does not provide a mirror URL, default originate Nexus repo is used. Otherwise provided Nexus repo will be used what can speed up process of building application drastically.