Agile design principles

May 10th, 2022

I may have mentioned this before, but I’m a bit of a nerd for design principles. Have I shown you my equivalent of an interesting rock collection lately?

If you think about design principles for any period of time, it inevitably gets very meta very quickly. You start thinking about what makes for good design principles. In other words, you start wondering if there are design principles for design principles.

I’ve written before about how I think good design principles should encode some level of prioritisation. The classic example is the HTML design principle called the priority of consitituencies:

In case of conflict, consider users over authors over implementors over specifiers over theoretical purity.

It’s wonderfully practical!

I realised recently that there’s another set of design princples that put prioritisation front and centre—the Agile manifesto:

• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

And there’s this excellent explanation which could just as well apply to the priorty of constituencies:

That is, while there is value in the items on the right, we value the items on the left more.

Yes! That’s the spirit!

Ironically, the Agile manifesto also contains a section called principles behind the Agile manifesto which are …less good (at least they’re less good as design principles—they’re fine as hypotheses to be tested).

Agile is far from perfect. See, for example, Miriam Posner’s piece Agile and the Long Crisis of Software. But where Agile isn’t fulfilling its promise, I’d say it’s not because of its four design principles. If anything, I think the problems arise from organisations attempting to implement Agile without truly internalising the four principles.

Oh, and that’s another thing I like about the Agile manifesto as a set of design principles—the list of prioritised principles is mercifully short. Just four lines.