Uh, given that you don't respect ocaml's memory model and force -safe-string, that's just not true. Any Obj.magic that is correct in OCaml is probably not going to be correct in bucklescript.
`-safe-string` is the future. Any compiler can not guarantee its correctness if you write crazy code , `Obj.magic` here.
I am not interested in core personally, but I don't see any reason why it will not work if it is vanilla OCaml
Did you actually tried to compile core ?