A more conventional dep name, 'time syncronised'.
Deal with zsh in 'dir in path'; non-interactive bash ignores this.

I'll have to sort out bash later, but this will do for now.
Install 'curl' on non-apt systems (like arch).
Install 'ntp' for `ntpdate` on arch.
Update to ruby-1.9.2-p484 for CVE-2013-4164.
Install 'postgresql' on arch.
Add a dep to create the postgres datadir (required on arch).
Include the minor version in the arch postgres datadir path.
Render and the postgres config and restart on arch.
Oops, pass version to 'postgres datadir'.
Lawl, make the postgres datadir (-p)roperly.
Run systemctl on arch as root.
Use the standard arch postgres datadir path, sans minor version.

Having the minor version in the path would be nice, but it would require customising the systemctl script, which isn't worth it for now.
Add an arch postgres config with the correct paths.
Add the arch path to pg_hba.conf.