Servant
Haskell DSL for describing, serving, querying, mocking web apps
...From a single API specification, developers can derive server implementations, client libraries, documentation, and more—ensuring consistency and type safety across the stack. We have a tutorial that introduces the core features of servant. After this article, you should be able to write your first server web services, learning the rest from the haddocks' examples. The core documentation can be found here. Other blog posts, videos, and slides can be found on the website. The core documentation can be found here. Other blog posts, videos and slides can be found on the website.