(When you look at the blog, you'll see that the last blog update was in 2018, and you might conclude that the project is dead. But it's actually not -- their Github repo is still getting new commits!)
I believe the Reason syntax for OCaml is now maintained by the same people as Melange; which is the revived version of BuckleScript, the OCaml fork targeting JS, from which Reason and later ReScript spun off.
(When you look at the blog, you'll see that the last blog update was in 2018, and you might conclude that the project is dead. But it's actually not -- their Github repo is still getting new commits!)