I would call them a major user, but sponsor not so much. Their investments in the ocaml ecosystem have mostly been self serving...driven by what they need, not what the ocaml community as a whole needs. Contrast this with Sun/Java, Microsoft/DotNET, Google/Go, etc., where development is happening on what developers everywhere are looking for.

Actually, we've funded lots of things that we don't directly use. For example, we funded the development of OPAM, which we don't use internally at all. Moreover, the funding of OCaml Labs was aimed broadly at improving the OCaml ecosystem, rather than just addressing our narrow internal needs. Our work and funding on compiler improvements like Flambda is aimed at things we want, but they're also of broad utility to the users of the language. Merlin is another example of something we've supported that is useful to us internally, but also useful more broadly.

This is of course self serving in the sense that we think the OCaml ecosystem is important to our future, and so we want to help it flourish. But it's a relatively enlightened form of self interest...

That's fair, I wasn't aware that OPAM was funded by JS. It is definitely one of the better package managers that I've worked with too.

I'd like to ask you a question, as it isn't every day that yminsky responds to me. If you knew from the beginning that you would end up creating an entire ecosystem (including libraries, package managers, etc) mostly from scratch, would you have chosen SML instead? I know when you joined JS that OCaml was probably the pragmatic choice. But so many ML enthusiasts (myself included) prefer the syntax and semantics of SML and end up using OCaml/F#/Scala because the SML ecosystem is so non-existent.