In the experimental branch I've just implemented the support for ANTARES_INIT_LOW/ANTARES_INIT_HIGH/ANTARES_APP macros and initcall's. Don't ask how, it's an utter hackery inside and you still have to supply your own main() and call do_antares_startup() there, but it's still better than nothing and allow for more library portability.
I've also fixed nRF24 library so it now compiles by SDCC, so rf24boot can now be ported to 8051 and other SDCC-based architectures. The bad thing is, that since SDCC can't ditch unused fucntions rf24 library uses up ~12KiBs of flash space. 14 If you disable hacky size optimisations.