This month I focused on the SDK. I set out to substitute configd with the SystemConfiguration framework from the SDK. This means the framework and its dependencies need to build from the bootstrap-tools so I had to add print-reexports to the bootstrap tarball. Then I ran into the familiar issue with XNU no longer providing all the availability macros and I set out to patch the affected parts of the SDK. After making headway through two or three frameworks the realization of how many locations that would need to be patched set in so I needed a different approach. I've opted to patch Availability.h to redefine availability macros in terms of the modern __API_AVAILABLE style of macros, which are backed by the availability attribute provided by modern compilers. This means we give up the ability to compile things on Darwin that make use of the source releases with older compilers. Next step is figuring out why PCRE doesn't have pthreads available anymore when being built in stage 3.