Postgres Install on HassOS RPi 3

Does anyone know of a good guide for installing postgres on the same hardware (raspberry pi3b+) as runs the newly released HassOS?

I’m updating a system from haspbian, where I simply installed postgres on the pi and pointed the Hass recorder config at it.

There have clearly been a ton of changes since the last year, and I’m by no means a postgres expert. Can anyone help?