August 30, 2018

Why CDM resonates with Waterfallians and not so much with Agilisto's

Architecture often is a matter of perception.

Architects that consider that architecture to be a noun, often consider, for example, that a CDM (Canonical Data Model) is a solution to a problem. Architects that consider architecture to be a verb, are very likely not considering a CDM at all. And although I have very strong personal feelings against architectural artefacts like a CDM, I'll try to explain in this post, why they can be perceived as an addition to an IT landscape. I think that is also very much an issue with a historic touch.

The School of Waterfallians

When you're a Wterfallian, when you come from the Waterfall school, then architecture is part of the analysis and design phase. This phase ends with 'The Architecture'. And that "picture with the 1000 words compendium" will have to last for the rest of the project. So you have to design something, come up with an architecture that will remain unchanged for months if not years. Your data model is obviously part of your architecture and will be included. Soon you'll draw the conclusion that a durable architecture requires for CDM, because how else can you ensure that your design fits within the landscape of existing and future designs?
If you have been raised with the standards and values ​​of a waterfall organisation, then you also know that deviating from previous decisions is out of the question. That only causes delays and budget overruns. Waterfallic architects will often focus on edge-cases, because they have the experience that these are the reasons to double back on previously made decisions. Logical behaviour is therefore also that you want to have it, your list of edge-cases, as complete as possible before you get started. Waterfall is a self-reinforcing approach when it comes to architecture and culture.

The Agilista School of Architecture

If you come from the agile school of architecture, then architecture is part of the development phase. Architecture emerges. The architect is thus a developer, or better said, the developers create the architecture. The agile architect therefore only design the rules-of-engagement, they merely create the play-book. A comply-or-explain concept ensures that the architecture can emerge and the best architecture at that point of time can be defined by the developers. The best architecture within the current context emerges. So you do architecture (verb), and you do that by adhering to the rules. This is a continuous process, you have to play by the rules continuously. When we look at a CDM, we find that the CDM itself is not that exciting in an agile world, instead the rules that a (C) DM has to comply to are. They are the grammar of the language.
When you were raised with the norms and values ​​of an agile organisation, then you also know that sticking to earlier made decisions is out of the question. At least, if this is against better judgment. That only causes a huge waste of resources instead. The agile architects will focus on the most common cases, because they have the experience that these have to be realised first in order to create value, validate hypotheses and provide insight into the next steps to be taken. Logical behaviour is therefore also that you want to have the first use-case defined as soon as possible in order to get feedback. Agile is also a self-reinforcing approach when it comes to architecture and culture.

Culture and Values

The crux is in culture and therefore in standards and values ​​and therefore in accountability. When the performance of an architect is measured based on the number of times that decisions have to be reconsidered, then an ever decreasing number of this metric is, for a waterfallian, an indication that things are improving. For the agile architect the opposite applies and an ever increasing number of reconsiderations will be better... or not.
Because the agile architect does not double back to earlier decisions, as the agile architect tries to find the best decision for a situation every single time again.

Hmmmm, then how would you evaluate the performance of the agile architect? That question is in fact not that hard at all to answer. The agile architect is not about the architecture but about the rules. The more stable they are, the better. At the same time, the rules have to be sufficiently complete to be able to develop products that offer the organisation a bright future.

The Architecturally Challenged

Who has the more challenging task? The Agilista or the Waterfallian?

That can not be answered, because they can not coexist. But it does make it clear that both have a big challenge. Each in their own system.

The waterfallic architect is mainly concerned with analysing and specifying everything in advance. It is someone who is good at overseeing many concrete aspects. She is someone who knows a lot, someone who thinks in as-is and to-be. That is to be expected, because in a waterfall organisation the architect is often the person with the most experience with a product or product group. The focus is mainly on 'what' and 'how' in the 'why, what, how' system.

The agile architect is mainly concerned with understanding the dynamics of the organisation. She is someone who is good at working at the abstract level and thinks in concepts. It is someone who understands a lot, someone who thinks in from as-is towards to-be. That is to be expected, because in an agile organisation is often the architect who has the most experience in how the organisation has developed. The focus is mainly on 'why' and 'what' in the 'why, what, how' system.

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The text very explicitly communicates my own personal views, experiences and practices. Any similarities with the views, experiences and practices of any of my previous or current clients, customers or employers are strictly coincidental. This post is therefore my own, and I am the sole author of it and am the sole copyright holder of it.