For an approach that does this, check out how Racket's web server manages statelessness across requests:
http://docs.racket-lang.org/web-server/stateless.html#%28par...
http://cs.brown.edu/~sk/Publications/Papers/Published/pcmkf-...
http://docs.racket-lang.org/web-server/stateless.html#%28par...
http://cs.brown.edu/~sk/Publications/Papers/Published/pcmkf-...