Hey - we are phasing it out, and the 0.9.1 release will ship with a subset (which can be previewed on the android_linux branch). We're mostly beholden to
filesystem being distributed with gcc & clang, which both have only experimental support, last time I checked.
I'm guessing you're asking because you have a need for a newer version, or a library that we're stripping out of 0.9.1. Is that the case?