We use pure functional programming in production to manage airline pairing/rostering and optimisations. Each customer has about 150k lines of pure functional co

We use pure functional programming in production to manage airline pairing/rostering and optimisations. Each customer has about 150k lines of pure functional code running on their servers. Also, Google “Elm” for examples of a pure functional language being used in production by other companies and how Facebook and other companies use Haskell in production.