PyFlow is a github MIT licensed python nodal framework creation system like Softimage XSI ICE or Fabric Engine that currently works standalone and with Maya, 3D Max and other app with pyqt/pyside.
Not sure how this projects MIT license would effect interfacing with Blenders GPL license.
Depends on QT so probably is a no go, also uses python 2, so is a sure no-go (Blender uses the lastest python 3.x series wich is incompatible with the 2.x code) . Maybe during the future everything nodal development time a system like this will be considered, but probably will be 1 or 2 years ahead, since the 2.8 series have to be stabilized first, bugs need to be squashed, on-hold projects to be merged need to be updated and merged, and so on.
The industry standard software will move from python 2.x to 3.x in 2020, so i don’t think these guys will have any motivation to make the move anytime soon.
I think they are working on something similar with the everything nodes