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Recent commits have allowed us to create extensions with code and dependencies that can be included conditionally. This will allow MiNiFi C++ consumers to select the features that they desire, help us build a cohesive API within libminifi, and support patches/upgrades with shared objects. The next first step is to move functional components into this paradigm.

The first component to move will be processors. There has always been a small selection of base processors within MiNiFi. Moving these to a separate extension will allow consumers to include processors conditionally. The design of this extension will be specialized to allow processors/or controller services to be selected in groups or individually. Further, these selected components will be built within the executable and as a shared object that can be versioned as a deliverable to MiNiFi agents. This will be integral to the update framework that will be discussed shortly.

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• The major negative to this has been one we've already experienced: increased cost in vtables lookup and class loader lookup 1. While we can't combat the former, we have done some work with template meta programming to fight the latter. More can be done; however, the cost will always exist, but is traditionally very minimal and paid at startup. Nonetheless, we already pay these costs so it will be difficult to argue that we pay the cost more. 
• Design complexity may make development more difficult.
• Debugging may become more difficult due to the depth of call graphs. 

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