well that was interesting, beginning to wonder if the documentation is written for the most recent version.. not the "stable" version.
Links I went to
https://kea.readthedocs.io/en/kea-2.4.0/arm/install.html
https://cloudsmith.io/~isc/repos/
https://www.postgresql.org/download/linux/debian/ -- Watch live at https://www.twitch.tv/chronoglass