It's a good question. Reason includes some major syntactic conveniences that make the JavaScript interop more pleasant to work with. One of the biggest ones is

It's a good question. Reason includes some major syntactic conveniences that make the JavaScript interop more pleasant to work with. One of the biggest ones is that it introduces a first-class syntactic JavaScript object literal (i.e. a Reason/BuckleScript value which will compile down to a JavaScript literal) and which makes writing JS objects much more pleasant. There are other conveniences as well, including the fact that Reason comes with a tool (refmt) that can autoformat your code to a standard style, wiping out style guide arguments etc.