Extensible, scriptable window managers are emerging as a useful alternative to traditional window managers. A window manager written in such a way as to allow "scripting" of its components makes it easy for a anybody to add their own features to the window manager. However, most such scripting features are relatively weakly typed and somewhat unsafe: it is easy to make errors in the extensions that aren't detectable to you run the extension.

An alternative is to use a strongly-typed language as the scripting language, along with runtime-loadable plugins. In this approach plugin code is type checked against an API to ensure its safety, at compile time, providing greater assurance that extensions will behave properly.

In this project you will develop a window manager. It will be scriptable in Haskell, possibly using the hs-plugins library. This will require making objects in the application available to the language, in a convenient manner.

• Core requirements for successful completion:
  • You should develop a minimal window manager, written in Haskell. It should be extensible via Haskell plugins.
  • There should be a suitable design and implementation of a mechanism for the interface between the window manager and the plugins.
• Extra tasks for the ambitious:
  • As well as being able to script the application in Haskell, you could provide a convenient embedded domain-specific language(EDSL) for scripting the objects of the application, in a more natural and convenient way than just raw Haskell.

• Lua, a powerful light-weight programming language designed for extending applications. Also, see Lua - an extensible extension language for the philosophy of embedded languages.
• Sawfish, an extensible window manager using a Lisp-based scripting language. Ion, a window manager scriptable in Lua.
• A proposal for a Haskell execution platform (an api to the compiler). Some Haskell interface tools.
• A library for compiling and loading plugins in Haskell.