[fhwang]

Generally speaking I like to have at least one CI environment available for every branch that makes you nervous, plus master. So what number you're dealing with depends on the team. Sometimes you have eight engineers but only four of them are doing something major at any given time.

Of course, whatever you call what you deploy to production -- master, production, timestamp tagging, etc -- it should ideally pass CI before getting deployed as well. And there are merge conflicts to deal with, too -- that ideally belongs to whoever's doing branching.

So, maybe my ideal workflow looks like this:

  * Branch away from master
  * As you work in your branch, grab a CI server if you feel like it (telling
    everyone else)
  * Commit code in your branch, keeping an eye on your CI as you go
  * Periodically merge in from master, dealing with merge conflicts in your branch,
    *not* in master
  * When you feel like it's ready to go, get whatever review you feel like you
    need -- code review, product manager review, etc
  * If you feel 99% certain it's good, merge it into master and push that back to
    origin
  * Wait for master CI to pass
  * Deploy to production
  * Beer

From an etiquette point of view, there are things that can go wrong, not least the individual commitment to deal with merge conflicts before they get involved in master. And conflict resolution cannot be rushed. If you have engineers who are just gonna edit files randomly to get git to accept their merge, you're going to have problems. (But if you have those sorts of engineers, you already have problems.)