libghc-happstack-server-dev 7.4.2-1build2 (arm64 binary) in ubuntu xenial

 Happstack is a Haskell web framework, designed so that developers can
 prototype quickly, deploy painlessly, scale massively, operate reliably,
 and change easily. It supports GNU/Linux, OS X, FreeBSD, and Windows
 environments.
 .
 Happstack provides you with all the components you need to build and
 deploy your application, which is completely self-contained.
 Particularly, Happstack provides the application with a distributed and
 persistent data storage layer, capable to interact with the application
 itself directly in terms of Haskell data structures.
 .
 Happstack-server contains the HTTP server itself.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.