AFAIK, the iemlib build system creates an iemlib1.pd_linux and iemlib2.pd_linux. For Pd-extended, all of the objects and abstractions are all put into an 'iemlib' libdir. So perhaps the first could be packaged as pd-iemlib1, pd-iemlib2, etc. and the 'iemlib' libdir could be pd-iemlib.
The 'iemlib' libdir could also be pdextended-iemlib, but then it will be annoying to use that library in anything but Pd-extended.
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