This is completely not pertinent to the actual content of the article, but I think there a slight error in the first paragraph of the article. Jsonb support was added as part of Postgres 9.4, at least according to http://www.postgresql.org/docs/9.4/static/release-9-4.html, right?
I ask because we're planning on using jsonb here soon, and we were hoping it would be available in the version of Postgres available in ubuntu 16.04.
JSONB is definitely in 9.4. We used that at the company I worked at previously. There might be improvements to it in 9.5 that I can't recall but it's definitely usable and production ready in 9.4
EDIT: Looks like [1] talks about what he was mentioning, there's a number of functions they added to improve the use and experience in 9.5.
I ask because we're planning on using jsonb here soon, and we were hoping it would be available in the version of Postgres available in ubuntu 16.04.