Quoting the LWN article:
"There must be a crowd of people out there thinking that they would get into
kernel development, but only if they could do it in Haskell. Here is a web site
with instructions on how to do just that. "By making GHC and the Linux build
system meet in the middle we can have modules that are type safe and garbage
collected. Using the copy of GHC modified for the House operating system as a
base, it turns out to be relatively simple to make the modifications necessary
to generate object files for the Kernel environment." This leads to code which
hello = newCString "hello" >>= printk >> return 0
"Just don't try to merge it upstream."
P.S.: Take *that*, clojure.