Release Planes versus Release Trains
There is a lot of talk these days about SAFe. I have a lot of respect for what Dean Leffingwell has done but there is a minor use of language that has been bugging me in recent days. Just as I disagree in using farm animals to describe people on a Scrum team, I believe the Release Train metaphor is dated and has its limitations. I believe, when doing Agile at scale, a Release (Jet) Plane offers a better representation of the complexity of enterprise level delivery processes.
When I think of a train, I think Amtrak in the NorthEast Corridor, the DC Metro, or School House Rock. I don’t think of a train when thinking of the most modern or efficient mode of transportation. So, why pick the train?
I get the metaphor:
- The train departs the station and arrives at the next destination on a reliable schedule.
- All “cargo,” including code, documentation, etc., goes on the train.
- Most people needed on the train are dedicated to the train.
When speaking to architecture, SAFe refers to architectural runway, not architectural train tracks or a rail-yard. It’s a mixed use of transportation metaphors that is not explained. The runway is a perfect alignment with my Release Plane metaphor.
- Most people needed on the plane are dedicated to the plane. Sure, each plane has a flight crew but they also have a ground crew at each airport (DevOps).
- All “cargo,” including code, documentation, etc., goes on the plane. I also recognize that some cargo is more valuable than others. Let’s put them in first class or allow early boarding.
- Planes depart airports and arrive at the next destination on a reliable schedule, unless you fly American Airlines.
A few more comparisons:
- When you go to the airport and try to get you and your luggage on a plane, don’t you and your luggage (the cargo) go through a series of checkpoints?
- If you don’t get past a checkpoint, do you still think you’re going to get on the plane? This should be pointed out.
- Doesn’t everyone have to comply with cargo size limitations? Again, this should be pointed out.
None of these additional comparisons apply to the release train metaphor as well as the release plane.
I just thought I would bring this up. Can you think of any other things that would apply to my plane metaphor? Maybe we’ll see the release plane used in SAFe 4.0.
There are others on the ground protecting you while in the air. Air traffic controllers insure that no one gets in your path and that obstacles are removed. Executives and Program Management should provide that protection.
Steve, I totally agree. There should be someone or a group who see the bigger picture. They see the obstacles. Air traffic controllers would be a great addition.
Mike – another attribute of a train metaphor is the capacity to add or remove cars to the train before it leaves the station.
So multiple Dev teams may have indepemdent components that either make a release or not. That is their car being hooked up to the release engine with associated marketing, installation process, doc version, etc.
The “release train” metaphor makes more sense perhaps in countries with better rail services? It’s more a reflection on the standard of train services where you live perhaps, as a lot of the “advantages” with air travel that you cite also apply to train services elsewhere.
Some countries offer the equivalent of ground crew and check-in for trains, in Europe for example.
Christopher, that one made me think. Thank you. I did not consider Europe, when comparing train versus plane service. That said, I wonder if SAFe is getting as much press in Europe as in the States.
I agree with 90% of what is here, yes plane makes more sense with both runway, the rest of metaphor and the fact that most business people actually take planes BECAUSE they are more Agile / Lean. A train is tied to its tracks, etc and moves slower generally speaking.
SAFe draws the agile release train on their diagrams like a bullet train so I see that intention related to high speed. The only advantage to the train metaphor in my mind is the EASE with which a person can get on or off a train. Lean-Agile does talk about ease of transitions, whereas the airport is anything but an easy transition.