I tried to install fabtests from the 1.8.1 release tarball on macOS, but could not. The make step complains about not finding <osx/osd.h> and indeed that file is not included in the release tarball. include/freebsd and include/windows are missing as well. Building and installing from the v1.8.1 git tag works and allows me to run runfabtests.sh against the sockets provider with 71 passed tests, 1 excluded.