https://clojure.org/community/success_stories
https://clojure.org/community/companies
https://ocaml.org/learn/success.html
https://wiki.haskell.org/Haskell_in_industry
https://gist.github.com/ekalinin/04a538f2918b4685fcfd65982e471ee9
http://fsharp.org/testimonials/
erlang is or has been used by facebook, whatsapp, eletronic arts, alcatel, t-mobile.
https://news.ycombinator.com/item?id=9248107