Yes, it's announcing that the next but one version, 5.0, will support multicore and effect handlers. For what it's worth you can actually start using Multicore

Yes, it's announcing that the next but one version, 5.0, will support multicore and effect handlers. For what it's worth you can actually start using Multicore OCaml today, there are installation instructions on the wiki: https://github.com/ocaml-multicore/ocaml-multicore https://github.com/ocaml-multicore/ocaml-multicore