@dmit, we will have to agree to disagree there; the reality is, only a very few people are using the absolute latest OCaml features. If you look at the Opam package build matrix: http://check.ocamllabs.io/ ... most Opam packages are building against 4.02 to 4.05. And OCaml in 2020 is great but it's still not close to what we need for wider adoption in its chosen native compilation space. BuckleScript/Reason is a different strategy, which actually does seem to be working for that goal.