ajhc (hackage): Ajhc is a fork of jhc. The jhc is a haskell compiler which aims to produce the most efficient programs possible via whole program analysis and other optimizations.  The jhc is very minimalist in that it does not have a precompiled run time system, but rather generates what is needed as part of the compilation process. However, back ends do have specific run-time representations of data, which can be affected by things like the choice of garbage collector.  Perhaps you can get internal overview with following compile flow image:
Keywords: compiler|gpl|library|program