Tean years ago I moved to Silicon Valley from London to work at a hardware company. I realized pretty quikly that I wanted to do software not hardware. Algebraic datatypes, static typing, ..., were also more natural to me than OO and classes. So I 'learned' OCaml in a week, applied to a software dev job at a startup and got hired (I got extremaly lucky obviously). My secret love was Haskell and I later joined companies using Haskell in production. I then transitioned to engineering management.

Long story short - my experience has been that OCaml (and Haskell) are often better phased out as the maturity of the team grows. I hope that one day I that will change - but as of today I would not advise a startup to bet on functional languages like OCaml. Happy to elaborate as to why if there is some interest.

I'm looking forward to hearing from people who disagree; and more importantly, have built successful products in OCaml.