+10 on making the tier platform support explicit. I would vote not to require involving the SC in the tier changes unless there is a strong reason to do so (e.g. there is controversy, or e.g. Tier 1 implies a commitment of PSF infrastructure). The SC has a lot of decisions to make as it is & hopefully Tier 2 and 3 are really about checking a checklist (are there enough core devs committed, are the buildbots in place, etc) that is already defined in the PEP. Replies to some other replies in the thread: I like Christian's idea of explicitly supporting platforms such as manylinux2014, Debian stable, Ubuntu stable where C extensions are commonly built. It would help make those de facto standards more official. Or some of the platforms supported by cibuildwheel (to include non-Linux platforms). I would prefer having the list in a PEP rather than the devguide. The devguide is important, but it doesn't feel like a canonical reference place for this sort of information. Regards, Simon