Hey Guys, Perhaps I shouldn't have sage-clib with use=mpir enabled, but if I do the sage-clib-4.4.4-importenv.patch fails because the first hunk in sage-clib-4.4.3-replace-gmp-with-mpir.patch has already overwritten gmp with mpir. I'm not sure but perhaps the sage-clib-4.4.3-replace-gmp-with-mpir.patch should also have the environment stuff that's in the first hunk of sage-clib-4.4.4-importenv.patch. Steve P.S. The parallel build of sage-core now only takes several minutes here with 4 cpu cores. Of course ccache was enabled so a fresh build would take a bit longer.