This is fairly old. HAppS has been developed further into Happstack:<p><a href="http://en.wikipedia.org/wiki/Happstack" rel="nofollow">http://en.wikipedia.org/wiki/Happstack</a><p><a href="http://happstack.com/" rel="nofollow">http://happstack.com/</a><p>Here is a quick intro:<p><a href="http://happstack.com/docs/crashcourse/index.html" rel="nofollow">http://happstack.com/docs/crashcourse/index.html</a>