Postgres 9.5 on Travis CI

Update: As of December 1, 2016, Travis has made both 9.5 and 9.6 available on Trusty containers so most of what’s said in this article is no longer relevant. Please refer to their standard documentation for information on installing Postgres.

The recent release of Postgres 9.6 has brought into sharp relief that Travis still doesn’t even have widely available 9.5 support quite yet. I was recently trying to get a 9.5 database running there, and was somewhat confused by the current state of affairs, so I’m writing this. There’s a big GitHub thread on the subject, but it’ll take some reading to gather context.

So for your convenience: Postgres 9.5 is supported, but only for non-container builds ¹. Here are the .travis.yml incantations necessary to get it running:

dist: trusty
sudo: required
addons:
  postgresql: "9.5"

A few Travis employees have indicate that they’re trying to get 9.5 support on containers, but their comments were from ~1.5 months ago (as of this writing) and there doesn’t seem to have been any progress yet.

I’ll try to keep this post up-to-date as I’m made aware of new developments.