The Hortonworks Release Engineering team hosts all the released HDP maven artifacts at http://repo.hortonworks.com/content/repositories/releases/.

Other than the release artifacts, some non-Hortonworks artifacts are necessary for building the HDP stack. These third-party artifacts are hosted in the Hortonworks nexus repository:

http://repo.hortonworks.com/content/repositories/jetty-hadoop/

and

http://repo.hortonworks.com/content/repositories/re-hosted/

If developers want to develop an application against the HDP stack, and they also have a maven repository manager in-house, then they can proxy these three repositories and continue referring to the internal maven groups repo.

If developers do not have access to their in-house maven repos, they can directly use the Hortonworks public groups repo http://repo.hortonworks.com/content/groups/public/ and continue to develop applications.