Looks like limited support has been added to 2.6.x but I suspect we will see GIMP moving in this direction in future releases.
The Generic Graphics Library (GEGL) is a programming library under development for image processing applications. It is mainly developed for GIMP in order to bring support for higher–bit-depth images than GIMP currently supports, as well as non-destructive editing. It has been partially implemented in GIMP 2.6 and may be used by other software too.
GEGL was originally conceived as a GIMP core replacement in 2000, finally in 2006 the external API was deemed stable enough and capable of replacing the GIMP core. On 20 December 2007, it was added to the development version of GIMP. Some of GIMP's tools have already been converted to GEGL operations; mostly tools which modify colors, brightness or contrast have been converted.
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