latest perf tuning info

Many years ago, I considered myself fairly expert when it came to
performance tuning and query optimization in postgresql, but I've been
hiding out inside (insert big company that doesn't use Postgresql here) for
a long while while postgresql has continued to evolve, and much has changed
since Greg's book shipped in 2010. I'm wondering if there is anything more
up-to-date than that excellent reference, especially anything that touches
on tuning and performance in AWS - RDS or running it directly on an EC2
instance.

But really, I'm mostly looking for documentation on query optimization and
tuning for developers, rather than administration stuff. I've got a lot of
fairly inexperienced engineers bumping into their first performance
problems resulting from very naive schema and query design as datasets have
started to get large, and I'd rather point them at good documentation than
just do their tuning for them. It's all low hanging fruit right now, but it
won't stay that way for long.

Thanks,

--sam