For all of you projects that are working as raw processors ahead of GIMP, mitch has a means for changing the image importer used.
From mitch over on #gimp:
GIMP now allows to configure the RAW digital cameras image importer used. In order to be listed in the new “Preferences → File Import/Export → Raw Image Importer” section, RAW import plug-ins must register their load procedures as handling RAW images. In the plug-in’s query(), simply call
gimp_register_file_handler_raw()
on the load procedures’ names.
See gimp/plug-ins/file-darktable/file-darktable.c as reference.