The release candidates for the first 1.73.0 beta release are now available at: https://dl.bintray.com/boostorg/beta/1.73.0.beta.1/source/ The release notes are not yet available. The SHA256 checksums are as follows: 44f323b42c4375ab3751b67ac5ce53ba5267af20cf375be75675d8952d3cca4e ./boost_1_73_0_b1_rc1.7z 5270fa89243a3508331bd3773800de6d2f98d1f160b95e362fa8269d9cd58773 ./boost_1_73_0_b1_rc1.tar.bz2 82ffcd4a2e558a31f1ddd6a54ef6c00dae28b95c2ddee575c285544085dcb004 ./boost_1_73_0_b1_rc1.tar.gz 910b7560ee239472cc69e6a0c680dc4d9d7ea234faad807738ec98e4811c63d4 ./boost_1_73_0_b1_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Boost Release Managers