[Ruby] Good description of the rails startup process?

[James Moore]

I got to the point where not knowing exactly what happens during Rails
startup was causing me headaches, so I started to walk through everything.

Is there a good description of this somewhere that I should be reading
(along with the code, of course) rather than starting from scratch?  Or even
worse, should I be taking notes and writing this up?

This is the sort of thing that I find a debugger extremely useful for.  I
find that just stepping through with the debugger helps my understanding
more than just an offline read of the code.

 - James