Hi Everyone/Ken, BLAKE2's b2sum is available at https://github.com/BLAKE2/BLAKE2. In particular, the latest tarball is available at https://github.com/BLAKE2/BLAKE2/releases/tag/20190724. The 20190724 release includes SSE2, XOP, SSE4, AVX and NEON implementations.
There is an Autotools port from the makefiles to Autotools so 'configure && make && make check && make install' works as expected. The files are available at https://github.com/BLAKE2/BLAKE2/pull/63. A zip is available at https://github.com/BLAKE2/BLAKE2/issues/61. The files are in public domain so there are no license encumbrances. It should be fairly easy to add b2sum to MacPorts with the Autotools front-end. (b2sum is currently missing from MacPorts). Jeff