If you want to work with the CMS Services in the CTS environment then you must define a system landscape in the backend that also includes an upload system. The upload system is there to provide the development system with the necessary archives and sources.

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The graphic shows an example transport landscape with an upload system. The transport landscape consists of a development system, a consolidation system, a test system, and a productive system and associated runtime systems. The upload system is the first system of the transport route and supplies the development system directly with the SCAs that are required.