[oulu2006]

Have you done this postgresql/RDS?

Because when I last tried it, the replica has to be the same major version (WAL streaming requires it) and then upgrading it to the latest version can take 10+ hours.

Definitely nowhere near 5 minutes downtime.

[nijave]

You'd want logical replication instead of physical replication. Logical rep doesn't stream the WAL as-is, it streams a representation of the statement that can be replayed on the destination.

It looks like this uses pglogical plugin but there's also a built in decoder I think called "pgoutput"

[gfosco]

Self hosted postgres, not RDS.