At work we use Haskell, and have been for around 10 years. It's a delight for iterations and refactoring, as the solid foundations it bring relieve you of spending your time writing tests checking for rogue nils or undefined.
528 karma · joined November 8, 2015
See https://pauldownen.com/publications/anf-continued.pdf, https://www.reddit.com/r/ProgrammingLanguages/comments/13w3c... and https://langdev.stackexchange.com/a/2254 (as well as https://www.college-de-france.fr/sites/default/files/media/d... as a bonus)