CloudNative PG
I remember when people would tap their temple if you suggested running PostgreSQL in Docker. Now we have CloudNative PG (https://cloudnative-pg.io).
It is a native way to run PostgreSQL in Kubernetes.
It provides TLS, backups, replication, and HA out of the box.
In short, it handles all the main problems itself.
I have never liked dealing with PostgreSQL internals. So I use CloudNative PG in backfabric to deploy the database.
