Rob Hirschfeld's Blog

Four alternatives to Process Interlock March 16, 2012

Note: This is the third and final part of 3 part series about the “process interlock dilemma.”

In post 1, I’ve spelled out how evil Process Interlock causes well intentioned managers to add schedule risk and opportunity cost even as they appear to be doing the right thing. In post 2, I offered some alternative outcomes when process interlock is avoided. In this post, I attempt to provide alternatives to the allure of process interlock. We must have substitute interlocks types to replace our de facto standard because there are strong behavioral and traditional reasons to keep broken processes. In other words, process Interlock feels good because it gives you the illusion that your solution is needed and vital to other projects.

If your product is vital to another team then they should be able to leverage what you have, not what you’re planning to have.

We should focus on delivered code instead of future promises. I am not saying that roadmaps and projections are bad – I think they are essential. I am saying that roadmaps should be viewed as potential not as promises.

1. No future commits (No interlock)

   The simplest way to operate without any process interlock is to never depend on other groups for future deliveries. This approach is best for projects that need to move quickly and have no tolerance for schedule risk. This means that your project is constrained to use the “as delivered” work product from all external groups. Depending on needs, you may further refine this as only rely on stable and released work.

   For example, OpenStack Cactus relied on features that were available in the interim 10.10 Ubuntu version. This allowed the project to advance faster, but also limited support because the OS this version was not a long term support (LTS) release.

2. Smaller delivery steps (MVP interlock)

   Sometimes a new project really needs emerging capabilities from another project. In those cases, the best strategy is to identify a minimum viable feature set (or “product”) that needs to be delivered from the other project. The MVP needs to be a true minimum feature set – one that’s just enough to prove that the integration will work. Once the MVP has been proven, a much clearer understanding of the requirements will help determine the required amount of interlock. My objective with an MVP interlock is to find the true requirements because IMHO many integrations are significantly over specified.

   For example, the OpenStack Quantum project (really, any incubated OpenStack projects) focuses on delivering the core functionality first so that the ecosystem and other projects can start using it as soon as possible.

3. Collaborative development (Shared interlock)

   A collaborative interlock is very productive when the need for integration is truly deep and complex. In this scenario, the teams share membership or code bases so that the needs of each team is represented in real time. This type of transparency exposes real requirements and schedule risk very quickly. It also allows dependent teams to contribute resources that accelerate delivery.

   For example, our Crowbar OpenStack team used this type of interlock with the Rackspace OpenStack team to ensure that we could get Diablo code delivered and deployed as fast as possible.

4. Collaborative requirements (Fractal interlock)

   If you can’t collaborate or negotiate an MVP then you’re forced into working at the requirements level instead of development collaboration. You can think of this as a sprint-roadmap fast follow strategy because the interlocked teams are mutually evolving design requirements.

   I call this approach Fractal because you start at big concepts (road maps) and drill down to more and more detail (sprints) as the monitored project progresses. In this model, you interlock on a general capability initially and then work to refine the delivery as you learn more. The goal is to avoid starting delays or injecting false requirements that slow delivery.

   For example, if you had a product that required power from hamsters running in wheels then you’d start saying that you needed a small fast running animal. Over the next few sprints, you’d likely refine that down to four legged mammals and then to short tailed high energy rodents. Issues like nocturnal or bites operators could be addressed by the Hamster team or by the Wheel team as the issues arose. It could turn out that the right target (a red bull sipping gecko) surfaces during short tail rodent design review. My point is that you can avoid interlocks by allowing scope to evolve.

Breaking Process Interlocks delivers significant ROI

I have been trying to untangle both the cause and solution of process interlock for a long time. My team at Dell has an interlock-averse culture and it accelerates our work delivery. I write about this topic because I have real world experience that eliminating process interlocks increases

1. team velocity
2. collaboration
3. quality
4. return on investment

These are significant values that justify adoption of these non-interlock approachs; however, I have a more selfish motivation.

We want to work with other teams that are interlock-averse because the impacts multiply. Our team is slowed when others attempt to process interlock and accelerated when we are approached in the ways I list above.

I suspect that this topic deserves a book rather than a three part blog series and, perhaps, I will ultimately create one. Until then, I welcome your comments, suggestions and war stories.