Hi @MarkNZed
Welcome to this forum!
The flows Node-RED creates are held & stored in a JSON format, that usually can be read by a lot of tools. The challenge is to create an alternative runtime to execute this definition & bring it to life. We've realized this idea for node-red-mcu ... and it's not simple! 
EDIT: @BartButenaers recently did a nice sketch of the ecosystem we created for node-red-mcu that might give you an additional insight.
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