Haskell in the Wild

Functional programming (particularly Haskell) is used by a growing number of companies today, including some large multinationals.

Companies that use Haskell

There are lists of companies that use Haskell on the Haskell web site and on Quora. A few highlights are Facebook, IBM, Twitter, AT&T, Bank of America, Barclays Capital, NVIDIA and Microsoft.

Some interesting links are:

• Facebook uses Haskell in several projects, for example Fighting spam with Haskell.
• Galois has been an active Haskell user and promoter for over a decade. This talk introduces three case studies from some of their projects.
• The New York Times has a nice talk about Haskell in the newsroom.
• Running a Startup on Haskell.

Companies that use functional programming languages other than Haskell

• Twitter uses Scala, an FP with Java syntax running on the JVM. How and why Twitter uses Scala.
• Walmart uses Clojure, a dialect of the Lisp programming language. Walmart runs Clojure at scale.
• Bloomberg uses OCaml, an object-oriented version of the ML programming language. OCaml at Bloomberg.
• SocialText uses LiveScript, a functional language with many similarities to Haskell, which compiles to JavaScript. Read about their experiences.

Do you know of any other major tech companies that make use of functional programming? Do let us know in the comments section below.