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• <systemDetails>: Defines system metadata that is used by tools and emitted by an xvm in heartbeats. 
• <env>: Defines environment variables that can be used for substitution of values in the document and are exposed to the application and talon runtimes.
• <busProviders>: Defines custom message bus provider implementations. 
• <buses>: Defines the message buses that are used for applications to communicate with one another.
• <apps>: Defines and configures the applications that make up the system. 
• <xmvs><xvms>: Defines the xvms (Talon lightweight containers) that host one or more applications. 
• <profiles>: Defines profiles that can be dynamically activated to localize the configuration for different operating environments.

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