The dark side of git...

Git is Great!

As a distributed source code tool, git is great. I love that when I'm on an airplane I can commit code without a wireless connection and have be able to unwind what I was doing. It was clearly designed with the "offline" model in mind. The idea I can create a quick branch, experiment, make massive sweeping changes, and just drop the whole thing if I realize it sucked...is AWERSOME! For a fact this puts it ahead of it's open source predecessors (namely...SVN, CVS, and RCS).

But perhaps a victim of it's success

What I observe, however, is that a lot of folks have taken up a development model where "everything is a branch" and we end up with roles like "pull request approval engineer" (not a real title, but if you end up doing that job, you'll know that your doing it). This problem happens when the number of public branches/forks reaches a count and complexity that far exceed any value they could have possibly served.

What is productivity?

I'm going to take a somewhat unpopular stance here, but in general my stance is that branches are antiproductive... before everyone gets their pitchforks out, let me explain my version of "productivity" for a software project. Productivity is producing software that accomplishes the business purpose at a marginal cost that provides positive value. While that might have been wordy or even technically incorrect, the overall equality formula I wan to use is: sum of all activities to product the software must be less than the value the software provides. In other words, if it costs 2 million dollars to build/deploy some software, but the business can only recoup 1 million dollars in value (via cost saving or new sales or whatever) the I would consider that a failure.

The branching use case

As a software engineer, I want to create a branch so that other developers cannot see my changes in their builds.

Well that sucks because:

  1. First of all, the activity of creating the branch, merging in everyone else's branch to your branch (through possibly a different branch) is all stuff that you would get instantaneously for free if you were all working on the same mainline.
  2. Second, you're deliberately delaying visibility of changes from the rest of the team...which means the whole notion of continuous integration is getting thrown out the window
Which brings me to a key question

Are you operating with agility or fragility?

I would contend if you're branching for every feature or bug and merging them back in, your codebase and/or process is more fragile than agile.

Your Thoughts?

Comments

Joe Meirow said…
Whoa cowboy! I think your complaints aren't about "branching" as such. Your last two complaints:

I don't want experimental garbage in the mainline. So perhaps the actual complaint is that people let branches grow too large for too long before merging (testing is assumed).

Your last complaint about visibility is perhaps a function of decentralization. If we were using a centralized tool such as Perforce, you could see my unmerged branches. Of course you would also lose all the benefits that arise from the decentralized model. Just my opinion 🙂
Mike Mainguy said…
Yeah I realize I was picking on the pattern by using a specific tool as an example. The antipattern I'm really railing against is the notion of overbranching because "it's easy" and ignoring the effort of managing code conflicts between child branches and the mainline.

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