Boost release 1.77.0 beta 1 is now available at: https://boostorg.jfrog.io/artifactory/main/beta/1.78.0.beta1/source/ The SHA256 checksums are as follows: 7a3a025451dfa2923129214eef7d16b03c02310a353d02158a549f6caa4284b0 boost_1_78_0_b1.tar.bz2 c491b1dcb916195598aa6581d6708d57fcc750516641c22511c088d572de9c07 boost_1_78_0_b1.tar.gz 35e7a3b0eb412a3933e57c72ba96374eb7d88ff1f89dbec62a16d67ffea2105a boost_1_78_0_b1.7z e6b68feb2f63401c96ca9fe25e939b409189fbe526a6e784e4bd69832c8f09cb boost_1_78_0_b1.zip For details of what's in the release, see https://www.boost.org/users/history/version_1_78_0.html. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team