[racket] convert scribble block directly to xexpr?

Hi users,

Now that Racket has a state-of-the-art package system and a
smashing-success conference, I think the obvious missing element in
the path to world domination is our very own pastebin, so I made one
during the hackathon.

It renders a paste with scribble, to get syntax coloring and doc linking.

(Preview here: pasterack.org, http://www.pasterack.org/pastes/6444)

However, it is currently very slow because it naively writes a
scribble file to disk and then compiles it with a command line call,
because I couldnt figure out how to directly convert a scribble block
to html or xexpr. Does anyone know if this is this possible?