Having a single implementation of the hook framework makes sense. That said, technically, we could live with multiple implementations, as long as all implementations implement, for the usual obvious interoperability reasons, a single, common, well thought-out spec
In the past, I pointed at the TI-68k/AMS EvHk (Kevin Kofler) and tsrlib (Matthieu "flanker" Gallet) frameworks, the latter being more general and versatile. I remember the TI-Z80 experts replied that some of the things in there are, as expected, not applicable to the TI-Z80 and TI-eZ80 series - but some are, starting with the philosophy.
In the past, I pointed at the TI-68k/AMS EvHk (Kevin Kofler) and tsrlib (Matthieu "flanker" Gallet) frameworks, the latter being more general and versatile. I remember the TI-Z80 experts replied that some of the things in there are, as expected, not applicable to the TI-Z80 and TI-eZ80 series - but some are, starting with the philosophy.