The use case is that we want to sort a list of users by job title, where job title is a term reference to a dedicated vocabulary.
The sort is done by the job title term weight (defined via the vocabulary list).
I choosed to apply a custom sort function on a view, instead of a custom dynamic / entity query for two reasons :
Drupal 8 evolves quickly, and it's easy to get lost amongst the several documentations that have been written since the beta releases, Drush and PHP version needs upgrade. Some things that I have learned.
Option 1 : No VM setup on Mac OSX, via Homebrew
Okay, VM's are easier to maintain solutions, but in some situations you just don't have enough RAM for having Virtualbox running all the time.
I wondered if there was a solution to play around with Drupal 8 on a Chromebook (super cheap hardware / "everything in the cloud model" with a 16G SSD).
After some reddit I discovered that Koding.com provides you freely, in the browser, a VM / terminal plus a text editor for PHP and other popular languages (Ruby, Python, ...).
Open up your Koding Terminal and cd in the Web directory (default, single docroot for a VM).