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Don't Build a Thing

Part two of my agile architecture series.

Here is a real life example of where I treated a unknown project incorrectly. Why I handled this is badly and how I should have handled it if I could rewind time.

Whoops

An external client had a proposal for a web service which would power part their new web application. This service sounded very simple. Data import and some basic querying. There were plans to add additional bells and whistles at a later date. After an initial meeting development began.

A week later a second meeting was placed. A good few hours of development had been invested by this point. The meeting was useful, however some changes had cropped up. The data format had been modified, my solution could not handle the new format. Also the querying needed various modifications.

A week later, after several more hours of changes, the second meeting landed. There were more changes. This time technical adjustments based on the feedback from the clients' developers.

The third meeting introduced scope creep. Could this service handle any potential customer going forwards? It certainly could not at present.

You should see where this is heading. Eventually the requirements stabilized. Not until several days of my time had been taken up building something that was not needed, only to have to tear it down and salvage what I could.

The end result was a project I was not proud of. Due to my heavily invested time I wanted to save as much work as I could. It would be hard to tell my superiors we've wasted X amount of money. The project also lacked long term stability. Each iteration built upon the next. The feature to handle generic customers was tacked on. Had this been known from day one, things would have looked much better both in terms of code quality and architecture.

Solution

There is an easy way to transform a unknown project into a known project - build as little as you possibly can. Do this in the shortest amount of time to gather feedback, learn and defer decisions. After this process you will be in the best possible shape to tackle the project. These principles are the key to the processes within a lean start up.

How I Should Have Handled It

Starting with a minimal project in order to demo and deploy this would do nothing other than returned a hardcoded JSON literal. Enough to demonstrate and spark conversations.

During week two the discovery that a new data format had been chosen would not matter. The feature to load data had not been written after all. At this point the hardcoded data would be tweaked to match the new content. Easy.

Week three would pose no threat. Technical changes around best practices or technology are easily handled because very little code exists.

The newly required functionality discovered in week four would prototyped, estimated and agreed. As no real work has been done, adding this feature in would not only be achievable, it would be architecturally sound rather than bolted on as an after thought.

Why?

Deferring decisions such as the above is so useful that this can be applied to any project from my experience. Knowing how long a decision can be deferred is dependent on the scenario, but you will be pleasantly surprised in many cases at just how long decisions can and should be deferred. Even for known projects the power that deferral brings is so beneficial I tend to favour this style whenever possible. Build just enough to gather feedback and go from there.

The key point is that very little time and energy has been invested. In the second example of how I should have handled the client I invested hours of my time. In reality I invested days. I was invested in the first solution. The second solution however could be chopped, changed or thrown away with no protest. The act of throwing code away is so important, yet so rarely practised it will be the subject of the third part of this series.

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