Site and Foldkit's Router

Foldkit already routes. Its Router turns a URL into a typed route value and a route value back into a URL, and its runtime turns link clicks and history moves into Messages. foldkit-site does not replace any of that: every node of a Site is a Foldkit Router, and the Site's parser is Foldkit's oneOf and parseUrlWithFallback over them. What the Site adds is everything an application with several screens used to write around the Router by hand.

Foldkit Router      URL  <->  route value               (one address)
foldkit-site        route value -> place in a tree      (every address, and what is around it)

This page says where the line between them falls, what the Site does with each question it answers, and how it does it.