I'm not releasing the kernel or graphics library code for the moment (it's not finished, for one thing), but application sources will be available and drivers,

I'm not releasing the kernel or graphics library code for the moment (it's not finished, for one thing), but application sources will be available and drivers, etc, will all be open-source. The fixed 16KB banking window is a pain in one respect, namely that applications (which themselves are relocated into the banking window) cannot directly access MALLOCed RAM. Of course there are ways around this, but I was a little envious of the more flexible banking schemes on some of the Z80 platforms described in the SymbOS developer docs. But it's also fun working around the Atari's limitations.