Following the link to the blog of the author I found a blog post titled “postgres cluster management system in GoCardless”

http://www.interdb.jp/blog/pgsql/pg_pacemaker_01/

Which in turn lead me to

https://github.com/gocardless/our-postgresql-setup

And in turn to a fifteen minute talk titled “Zero-downtime Postgres upgrades”

https://www.youtube.com/watch?v=SAkNBiZzEX8

Which was interesting and informative IMO.

After watching that one I was lead further via the YouTube suggested videos to a 45 minute talk titled “Tuning PostgreSQL for High Write Loads”

https://www.youtube.com/watch?v=xrMbzHdPLKM

Which I liked a lot as well.

I think anyone who came here because they are interested in the subject of the OP link might be interested in watching these videos.

Though disclaimer of course: These videos told me things I didn’t know about scaling PostgreSQL, because there is a lot I don’t know about that. But if you already know a lot about that then of course these videos might not be so interesting to you.