Also put library code in a library directory

And account for the odd-host-out. :/  See if you can spot it.

There will be no staging grid and the other two nodes in this grid went
elsewhere.

Define testing grid and production grid with a function they can share.

There is not going to be a staging grid.
There will be a testing grid and a production grid.
The testing grid will be loosey goosey.
The production grid will have incremental rollouts.

This is a bricked machine in the data center where running NixOS is hard.