A few weeks ago, I was sitting in the audience, waiting for my turn to speak at DevOps Days in Minneapolis. Just before me, Xe Iaso delivered a funny and thought-provoking talk on building a social network on a whiteboard. It was very well done and had me feeling nervous about following that session.

The talk is a bit of a satirical look at an interview Xe had for a company that tried to get them to derive an architecture for a large distributed system. It was interesting to hear Xe note that often we have architecture diagrams of what we'd like to have, but never an explanation of how we implement a large system, especially one that has to grow as our workload grows.

This talk was a nice analogy of how often we get into situations where many of us can't believe our system was structured this way. We often wish we could completely redesign things from scratch, and we'd do it better. Why didn't the previous engineers think things through?

Watch the talk. It shows how a lot of software is built. We build what we think we need, but when we get overwhelmed, or often when we get unexpected pressures from others, we make decisions that seem to be the best ones in the moment. However, a few years later, with a few of these decisions behind us, we realize that each of those choices was too short-sighted. We have a mess of software the seems cobbled together rather than well-engineered.

I don't believe we can engineer everything well from the beginning. I also don't believe in early optimization, mostly because I think we are asked to build a lot of things that are never (or lightly) used. Who uses the paintbrush in Word or the FACTDOUBLE() function in Excel? However, I do believe that we ought to write code that performs well the first time, following patterns we (should) know well. We certainly should assume that whatever code we write will see at least 10X more data in production than in dev/test, so prepare for processing more data.

I'm sure many of you know of a codebase and system that doesn't run well. I hope most of you have another application that does run well and is fun to work on. Hopefully, the goal of your organization is to turn out more software like the latter than the former.