Category Archives: Christopher Alexander

Why Process Matters

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I’ve been working on a talk for Smalltalks 2014 about Discovering Alexander’s Properties in Your Code and Life.

I don’t want it to be an esoteric review of Alexander’s properties.

That won’t satisfy my audience or me.

I want to impart information about how Alexander’s physical properties might translate to properties of our software code as well as illustrate poignant personal examples in the physical world.

But equally important, I want impress upon my audience that process is vital to making lively things (software and physical things). In his, The Process of Creating Life: Nature of Order, Book 2, Alexander states,

“Processes play a more fundamental role in determining the life or death of the building than does the ‘design’.”

Traditionally, building architects hand off their designs as a set of formal drawings for others others to build. Does this remind you of waterfall software development? There isn’t anything inherently wrong with constructing formal architectural drawings…but they never end up reflecting accurately what was built. Due to errors in design, situational decisions based on new discoveries made as things are built, better construction techniques, changing requirements, limitations in tools or materials, a building is never exactly constructed as an architect draws it up.

Builders know that. Good ones exercise their judgment as they make on the spot tactical re-design decisions. Architects who are deeply involved in the building process know that.

Alexander is rather unhappy with how buildings are typically created and suggests that any “living” process (whether it be for building design or software or any other complex process) incorporate the following ten characteristics.

He challenges us software makers to do better, too:

“The way forward in the next decades, towards programs with highly adapted human performance, will be through programs which are generated through unfolding, in some fashion comparable to what I have described for buildings.”

As software designers and implementers we know that nothing is ever built exactly as initially conceived. Not even close. Over the past decade or so we have made significant strides our processes and our tools that enable us to be more effective at adaptively and incrementally building software. My thoughts on some ways we have tackled these characteristics are interspersed in italics, below.

Characteristics of Living Processes

1.Step-by-step adaptive. Small increments with opportunity for feedback and correction.
Incremental delivery, retrospectives, stakeholder reviews
Repetitive incremental design cycles:
Design a little– implement–refactor rework refine–design…
Design/test cycles: Write specifications of behavior, write some code that correctly works according to the specification, test and adapt…
Tests and production code equally valued

2. Whatever the greater whole is always the main focus of attention and the driving force.
Working deployable software, minimally-marketable features

3. The entire process is governed and guided by the formation of living centers (that help each other)
Code with defined boundaries, separate responsibilities, and planned for interconnections

4. Steps take place in a specific sequence to control the unfolding.
We have a rhythm to our work. Whether it is test-first or test-frequent development, conversations with customers to define behavioral “specifications”, or other specific actions. In order to control unfolding we need to understand what we need to build, build it, then refine as we go. And we have tools that let us manage and incrementally build and record our changes.

5. Parts created must become locally unique.
Build the next thing so it fits with and expands the wholeness of what we are building. Consider our options. Refactor and rework our design. Make functions/classes/code cohesive. Bust up things that are too big into smaller elements. Revise.

6. The formation of generic centers is guided by patterns.
We have in mind a high-level software architecture that guides our design and implementation.

7. Congruent with feeling and governed by feeling.
Instead of just making a test pass, see if what you just wrote feels right (or if it feels like an ugly hack). Reflect on how and what we are building. Don’t be merely satisfied with making your code work. How do you feel about what you’ve just built? How do those using your software react to it? How do those who have to maintain and live with your code feel about it?

8. For buildings, the formation of structure is guided by the emergence of an aperiodic grid, which brings coherent geometric order
Software is structured, too…we’ve got to be aware of how we are structuring our code.

9.Oriented by a form language that provides concrete methods of implemented adapted structure through simple combinatory rules
We use accepted “schemas” to create coherent software systems. We have software architecture styles, framework support, and even pattern languages emerging…

10. Oriented by the simplicity transformation, and is pruned steadily
We can consistently refactor and rework our code with the goal of simplifying in order to enable building more functionality. We rebuild to create sustainable software structures. Even if we come back to some old working code and see how to simplify it, we can rework it taking into consideration what we’ve learned in the meantime.

Yet, let’s not be complacent. Agile or Lean or Clean Code or Scrum practices don’t address every process characteristic Alexander mentions. I am not sure that all these characteristics are important for building lively software. Alexander is not a builder of software systems, although he spent a lot of time talking with some pioneers and leaders of the software patterns movement.

Some process ideas of Alexander sound expensive and time consuming. Do we always need to reflect on how we feel about what we code? Sometimes we need to build quickly, not painstakingly. We need to prove its worth, and then refine our software. Our main thought may be on just simply making it work, not how it makes us or others feel. So how do we add liveliness to this quickly fashioned software? What’s a good process for that? Mike Feathers wrote about Working Effectively With Legacy Code, but there is a lot more to consider. Maybe that quickly fashioned software has tests, maybe it doesn’t, maybe some parts have a reasonable structure, and maybe other parts should be tossed.

We often build disposable and hopefully short-lived software. Problems crop up when that code gets rudely hacked to extend its capabilities and live past its expiration date.

There are most likely different processes for creating lively software, based on where you start, where you think you are headed, and how lively it needs to be (not everything needs to be fashioned with such care).

People are continually building new and better tools and libraries. There is a rich and growing ecosystem of innovative open source software. Process matters. I think we have a lot still to learn about building lively software. It is a heady time to be building complex software systems.

Making Strong, Lively Centers

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Making things with lively, cohesive centers (whether software, buildings, landscapes, educational experiences, or artfully designed bento boxes) involves hard work, practice, skill, reflection, and the development of a discriminating eye.

One great example of hard work over a long period of time was this bonsai boat tree I saw in Kyoto. This tree is over 600 years old!

Can you imagine the effort and attention the bonsai gardeners spent over the centuries to create, grow, and maintain this beautiful shape with its many centers?

I wish I could sit with great software designers and architects, soak up their wisdom, and then effortlessly incorporate that wisdom into my own code. I would love to write lively code without breaking a sweat. But that hasn’t been my experience.

My first Smalltalk code wasn’t very good. I didn’t immediately get the shift from procedural thinking, where I had to worry about controlling every aspect of the call chain, to that flowing object-oriented style where learning how to delegate responsibility was key.

To understand how to make my Smalltalk code lively (because of stronger centers) took practice and experimentation, reflection, and more practice. And letting go of preconceived notions that no longer fit.

As I program in a yet another programming language, I can’t avoid bringing along techniques I learned earlier. Some fit. Some do not. (I keep re-framing my notions of how to implement a good design). And I keep adding useful programming techniques to my toolkit.

Techniques for constructing well designed code is programming-language specific, even though underlying good design principles seem universal.

It took a while for me to realize that to become a better Smalltalk programmer I had to let go of my incessant urge to understand and control every little detail (I had to do that as an 8086 assembly language programmer, my prior language). Trust in polymorphism. Delegate. Don’t try to do too much in any one method. Don’t pass in too many arguments. Let objects take responsibility for their actions.

Even as I learned to let go of details, I still made dumb mistakes.

Initially I didn’t understand the difference between elegant and overly clever code (I liked Smalltalk blocks—er, closures). I didn’t realize the overhead of lots of closures that held on to context. I thought it was clever that my font management code held blocks that could read fonts from the file system (embedding references to external files in them for goodness sakes).

Seasoned Smalltalkers don’t make these mistakes. See this wiki page for a short discussion of Smalltalk and Closures and this Stack Overflow posting.

Was I tone deaf when it came to using blocks? I don’t think so. I just wasn’t paying attention to the right details. And I wasn’t looking in the right places for inspiration or guidance.

Instead of performing my own experiments, ideally, I should’ve been studying and emulating good examples. Such as the Smalltalk collection hierarchy’s use of closures. There, code blocks are used elegantly to execute differential behavior. The Smalltalk collection hierarchy is one of the most beautiful set of classes I’ve ever seen.

Fortunately, I had people around me who took the time to rewrite my code and explain to me why they did what they did. Consequently, I learned to write simpler, less clever, less resource intensive, more maintainable Smalltalk code.

Recently I have been programming in JavaScript. I was motivated to develop JavaScript code to front-end our client-side Java reference app we developed and use in our Enterprise Application Design course. For that initial programming exercise I took the stance that I’d use pretty much “stock” JavaScript libraries (hence me learning about JQuery) and keep things pretty simple.

Since that first whiff of JavaScript programming, I’ve been honing my JavaScript by learning more libraries and plugins and improving my programming skills. I am no expert. Not yet.

I’ve learned effective techniques somewhat randomly because I am not surrounded by JavaScript experts who teach me their craft. Combing through the Internet for advice and inspiration is haphazard and compounded by the fact that our notion of good programming practices evolves over time as languages and tools and libraries grow and evolve.

But now, after more time and experience, I can appreciate several coding practices that contribute to maintainable JavaScript. Such as:

Modules. At first, the coding technique to define a module just seemed confusing. It is. But modularity, which helps to define and separate code “centers” is really important. Not only does it strengthen a “center” by making it more defined (and encapsulated), it makes it more easily integrated with other code.

Being aware of variable scope and limiting it.

Not constantly searching and mucking with DOM objects on every event. Initially I was content if my JQuery searches were “optimized”. Now I am thinking how to avoid DOM references by caching appropriate state in my own variables.

Not blindly nesting anonymous callbacks, but defining functions and then using them.

These techniques contribute to better-defined untangled code centers. But I want to caution you: don’t blindly follow coding best practices without knowing about and buying into the rationale behind them. Arguably your code might be better if you do. But you won’t learn how to exercise judgment until you know more about why you are doing what you are doing. Understanding how to write code that has strong, lively centers takes time, feedback, and the right kind of experience.

When I first started programming in JavaScript I could not have appreciated these techniques. I needed to gain more experience before I could see their value. With time writing more code, looking at more good and bad code, discussions with others, and reflection, I have gotten better at JavaScript. I’m not sure what steps I could leave out to shorten this process. It certainly is easier to learn how to write lively code if you work with others who care deeply about the code they write and who willingly point out and explain the good bits to you when you are ready to absorb them. If you are fortunate to have wise souls around you, take advantage of their wisdom…then put in the time you need to become better.

What Makes for Lively Centers?

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In this blog I dig a bit deeper into what makes good, lively centers.

Let me introduce another property of lively centers: alternating repetition. Consider this photo I took of blooming plum trees in Kyoto.

The photo doesn’t do the scene justice. The flowering trees went on and on and on.

And on.

Forking off the thick trunks were ever thinner arching mossy green and dark branches covered with blossoms. Those blossoms seemed to float between branches forming a sea of pink. I could get lost in those trees.

Looking out over that landscape I felt peaceful, relaxed, and calm.

Earlier, walking the streets of Kyoto I snapped this photo (imagining the sign was inviting me to get with it, “chill out”, be calm and come inside to purchase whatever they were offering).

That sign made me laugh. It contrasts the difference between strong centers that reach out and grab me with the rather flat-affect of everyday more mundane centers. The sign made me curious, but not enough to go inside the shop.

Good alternating repetition doesn’t mean the same thing over and over again. It involves smaller sub-patterns of repeating structures. In preparing for our workshop on Alexander’s properties, I looked for an example of alternating repetition in my personal life. I jog. So it was easy to find alternating repetition in my running routine (Joe Yoder found it in his dancing).

I jog several times a week. I don’t do the same routine everyday. Once a week, typically on Thursdays, I do tempo training with my running coach. She makes me run harder than I’d like to normally do for either a specific distance or time, then has me run easily for a bit to recover. I repeat this hard run-easy jog recovery cycle 3 or 4 times a session. Other days I do my normal easy 3+ mile runs (outside when the weather permits) through town. On the weekends I do a longer run of an hour or more at a comfortable pace. I repeat this cycle each week, with variations due to the running season (winter is slower/less running than summertime) or whether I am recovering from an injury or getting back to running after traveling or recovering from a race.

Another property of strong centers is local symmetry. The photo of these shrines (again, taken in Kyoto) illustrates this.

The shapes of the rooflines, windows, and pedestals are similar, not identical. Slight variations make them more interesting.

Here is the welcoming Port wine and strawberry arrangement that my husband and I found in our Doro valley hotel room in Portugal.

Symmetrical. But berries are closer together on the right hand plate. The napkin folds differ. Perfect symmetry is less pleasing (at least to me) than near symmetry. Alexander claims that a hand-hewn quality strengthens centers (he calls this property “roughness”).

When I discover a strong system of centers I get an emotional kick. And there it is. You discover Alexander’s properties when you engage with the things in your life and form personal connections (rather than letting the scene just float by). Finding Alexander’s properties involves a bit of luck, developing a discriminating eye, and being on the alert for positive connections between what you are experiencing and/or making.

Making strong, lively centers is another matter altogether. Yet how hard can it be? Well…that is a topic for another blog post or two.

Discovering Lively Centers

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Two weeks ago, Joe Yoder and I conducted a workshop on Discovering Alexander’s Properties in Your Life at AsianPLoP, the patterns conference held in Tokyo.

I’m still reeling from the many feelings that were stirred up as I prepared for this workshop. Inspired by the beauty we found in Kyoto, I included several photographs I took of that very beautiful place. Each property was illustrated with some image that resonated strongly resonated with us (whether taken in Kyoto or not, each photo had a strong personal connection).

Before I tell more about the workshop, I want to give a gentle introduction to Christopher Alexander’s ideas on properties of things that have life. Fundamental to Alexander’s ideas is the notion of “centers” arranged in space. According to Alexander, things that have life exhibit one or more of fifteen essential properties, which include, among other things, strong centers and boundaries.

Alexander’s notion of a “center” is simple to grasp—it is a coherent entity that exists in space. Individual centers are important (and they exist at different levels of scale), but more profound is how centers are arranged in space to form a more integral whole. Alexander writes,

“The system of these centers pays a vital role in determining what happens in the world. The system as a whole—that is to say, its pattern— is the thing which we generally think of when we speak about something as a whole. Although the system of centers is fluid, and changes from time to time as the configuration and arrangement and conditions all change. Still, at any given moment, these centers form a definite pattern. This pattern of all the centers appearing in a given part of space—constitutes the wholeness of that part of space. It is this structure, which is responsible for its degree of life.”

Here’s a photo I took in Hawaii for a talk I gave several years ago on the Nature of Order at another patterns conference. It illustrates the notion of a strong center:

I like this photo because it shows that the center of individual orchid flowers are accentuated and strengthened by the brown spots and five petals that form a star shape that surround. Not only is there a “center” to each flower (the stamen surrounding the pistil); there are several “centers” that surround that innermost center.

And here is the photo we showed at our Asian PLoP workshop to illustrate strong centers found on the roof line of an Imperial Palace building in Kyoto:

I leave it to you to find all the centers in this photo. The center cap on the top of the roofline accentuates the gold flower underneath. Underneath that is another circular center. Below that a symmetrical scroll. And there are centers (gold flowers) arranged along the roofline. Centers, when arranged in a pleasing fashion, complement and strengthen each other.

Centers are strengthened by boundaries that surround, enclose, separate, and connect them. Here’s a photo I took in Yellowstone Park of a crusty boundary at the edge of a bubbling hot springs:

The boundary between the hot spring and the land surrounding is fluid and ever changing (witnessed by the salty stains left from evaporation at the water’s edge).

The wood slats wrapped around this tree at the Imperial Palace in Kyoto, protect it from the wooden brace and form a boundary between the tree and the support:

After, explaining and illustrating Alexander’s fifteen properties, we asked attendees to form groups to brainstorm and discuss Alexandrian properties that they found in their own lives. One group focused on Alexandrian properties they found in the Tokyo metro and railway system; another on the properties of bento boxes; and a third on properties in education and learning. I was surprised by the diversity (and how profound some of the examples were, even though at first blush they seemed straightforward and simple).
But that is the topic of my next blog post.

To close this post I want to share two photos that whimsically illustrate “life” my camera eye unexpectedly caught in Kyoto. This first photo is obvious:

The second takes a little bit of searching to find the “owl-like” creature:

Is Kyoto a magical place? I think so. It was amazing to discover human-like or animal-like images in photos of trees. I had no idea that those shapes were there until I looked at my photographs. My eye must have been unconsciously drawn to those shapes (but truly, I didn’t see them until I looked at the photos). Even more startling to me is the liveliness of inanimate things—whether a hand crafted software module or a carefully placed garden pathway—that is more subtle and also profound. When we find strong centers surrounded by other strong centers in designed things, there is a pleasing sense of discovery and wonder.