Firstly, I’ve stopped referring to the practices as such, in favour of calling them aspects. Practices always felt slightly wrong, but at the time I couldn’t think of a better way of describing what I wanted to be practical, rather than theoretical points. I think aspects still allows that practical focus, without giving the impression of being a prescriptive process. So the aspects are:

• workflow
• visualisation
• work in process
• cadence
• continuous improvement

How does the KFC triad fit into that then. Here’s my thought process, which focusses more on conceptual ideas.

• Kanban. In this context, Kanban is the tool. As I have become more interested in Systems Thinking, I have become less focussed on the tool. What is more important is the concept behind the tool. Kanban is a great way to create a pull system, but there are others; drum-buffer-rope and CONWIP are a couple. Kanban seems to be the one that’s easiest to explain, and the one that caught people’s imagination, but really its about Pull.
• Flow. Given the first concept is Pull, and we should flow where we can and pull where we must, then I think Flow comes under the concept of Pull. What I tended to find myself talking about with Flow, however, was what should flow. There’s not point having a pull system where work flows smoothly if the work is useless, so the second concept is really about Value.
• Cadence. Having identified Cadence as a Aspect, it can’t really be a concept as well. I talk about Cadence as a means of achieving predictability and reliability and of demonstrating capability. Cadence is just one way of doing this however, so the third concept is really about Capability.

So instead of KFC Development, I have moved to thinking of a Kanban System as a PVC System – one which exemplifies Pull, Value and Capability, and that can be described in terms of workflow, visualisation, work in process, cadence and continuous improvement. I quite like the ‘plasticity’ metaphor that springs to mind with this new triad; “the capability of being moulded, receiving shape, or being made to assume a desired form”. Its probably not very environmentally friendly though!

For me this also leads to the question of whether a process (such as, for example, Scrum) is a PVC System. That’s the subject of another blog post though!

A Kanban System visualises some unit of value. This unit of value could be a User Story, Minimal Marketable Feature, Plain Old Requirement or something else. This is different from a task-board, which generally focuses on visualising the current tasks.

A Kanban System manages the flow of these units of value, through the use of Work In Process limits. This is different from a task-board, which generally has no WIP limits, but aims to have all tasks complete by the end of a time-box.

A Kanban System deals with these units of value through the whole system, from when they enter a teams control, until when they leave it. This is different from a task-board, which generally only deals with the work in the build/test stage, but shows no information about what work is being prepared, or what work is ready for release.

By putting these 3 properties of a Kanban System together, we can describe a Kanban System for Software Development as one which allows value to flow through the whole system using WIP limits to create a sustainable pipeline of work. Further, the WIP Limits provide a mechanism for the Kanban System to demonstrate when there is capacity for new work to be added, thereby creating a Pull System. Finally, the WIP Limits can be adjusted and their effect measured as the Kanban System is continuously improved.

A task-board simply shows what development tasks have been predicted to be done in the current time-box, with their status.

Liz proposes a new format:

• In order to <achieve some value>
• As a <role>
• I want <some feature>

The <some value> is a MMF – Minimal Marketable Feature. However, where minimal is still quite big, then MMFs can be broken down into <features>, which are more traditional User Stories. Thus the format gives a simple way of managing the relationship between the small incremental functionality pieces, and the larger value pieces.

Thanks Liz and Chris!