(Shameless plug follows)<p>Take a look at my own Haskell operating system project Hos (<a href="https:&#x2F;&#x2F;github.com&#x2F;tathougies&#x2F;hos" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;tathougies&#x2F;hos</a>). Written in Haskell 98 using the JHC compiler (a bit outdated, but makes it easy to generate ANSI C from Haskell sources). Currently supports multi-tasking, interrupts, paging, garbage collection. Has the beginnings of a simple user-space ATA driver.<p>Patches welcome. E-mail me at travis@athougies.net if you want help setting up a development environment!