http://i3xi5qxvbrngh3g6o7czwjfxwjzigook7zxzjmgwg5b7xnjcn5hzciad.onion/proposals/327-pow-over-intro.html
Thanks to Solar Designer for the help in understanding the current PoW
landscape, the various approaches we could take, and teaching us a few neat
tricks.
Appendix A. Little-t tor introduction scheduler
This section describes how we will implement this proposal in the "tor"
software (little-t tor).