In this episode of Every Frame a Painting, Tony discusses the idea of showing character choice rather than just talking about it, using Snowpiercer as an example:
In nearly every blockbuster you've watched or tell-tale game that you've played, you've seen moments like this: the protagonist has to make a choice and there's no way to reverse it.
Just to be clear, I think moments like these are great and a foundation of good storytelling but I do wish in movies they weren't presented through dialog. So today I look at one possible alternative. In fact it's one of the oldest traditions in cinema. How do you show character choice? Left or right. That's it.In a similar fashion as many blockbuster and video game protagonists software architects regularly encounter complex choices that often can't be easily reversed. Or rather, the architecture we're designing experiences those complex choices (since in this metaphor we're working behind the camera and the architecture is the character on screen). But, unlike blockbusters and video games, software architects don't have the luxury of an audience that can simply watch the architecture evolve with each design decision made.
Even on small teams, generally only a few people at a time are in the room or at the whiteboard when a key decision about the architecture is made. In some ways it's as if we are asking downstream designers to watch only the last 10 minutes of Snowpiercer and then try to figure out why it's such a big deal for Chris Evan's character, Curtis, to do what he does. Without the context of these critical decision points that are constantly happening throughout a character's/architecture's journey, the audience/downstream designer loses significant rationale that could help explain a lot.
The Paths Not TakenWhile downstream designers can't watch the architecture make a choice on the silver screen (left or right?), we can still make it easier for developers who read our documents to playback the architecture's "character development" more easily.
Sometimes when trying to communicate design intent and rationale, it's more effective to say what you didn't do rather than what you chose to do. The method I'm proposing is pretty simple. Create a list of the architectural decisions you discarded with a brief note for why those decisions were rejected. With this list in hand, downstream designers have an opportunity to replay critical decision points and can now watch the architecture develop and mature. Left or right? What critical moments did this architecture face and what path did it end up taking?
Here's an example from a recent project. The basic problem involves figuring out how to integrate our client software with third-party, cloud-based web services that application developers using our software are starting to employ more frequently. The specifics aren't too important for the example, and I can't really share the specifics anyway.
|Path not Taken||Why this Path was Rejected|
|Create a cloud-based "services adapter" to buffer against changes in third-party services.|| |
|Release adapter as open source, have customers load it themselves|| |
|Offer a client library that makes it easier for developers to connect to third party services directly|| |
|No new support for web services integration in the client software|| |
With this background and context, its' pretty easy to see that the design choices we made kept our architecture on a path toward simplicity and tended to favor less code over more code. With this history and context, the list of design decisions that were rejected, it's much easier to understand why the resulting architecture is what it is. You're essentially replaying the architecture's definable moments. Hopefully with this information downstream developers won't scratch their heads when they see what might appear to be an odd outcome for the architecture/character. They can see for themselves the key decisions that led to the architecture/character becoming what it became and in turn internalize a significantly more nuanced appreciation for the architecture/character as a whole.
Again, the insightful Tony Zhou:
So, the next time you your character runs into a complex choice, who knows? Maybe it's actually just a simple matter of: left or right?