We propose a new extension to the purely functional programming language Haskell that supports compile-time meta-programming. The purpose of the system is to support the algorithmic construction of programs at compile-time.

The ability to generate code at compile time allows the programmer to implement such features as polytypic programs, macro-like expansion, user directed optimization (such as inlining), and the generation of supporting data structures and functions from existing data structures and functions.

Our design is being implemented in the Glasgow Haskell Compiler, ghc.