“Any fool can make something complicated. It takes a genius to make it simple.” – Woody Guthrie

What fans tend to love about Darcs is the simplicity of the user interface. In the Darcs team, we value the effort to put together a well-thought-out UI. We think a minimal amount of forethought is essential to preserving that unique combination of power and simplicity that Darcs offers.

Here’s the recommended route to adding a new feature. Keep in mind that we are not usability experts and we certainly do not expect you to be either. So we are not about trying to achieve perfection here, nor do we want to bog people down with Process. We just want to make sure we have a made a little bit of effort to get the UI right.

1. Propose the feature

2. Implement it?

It could be useful to prepare a prototype implementation of the feature. Having a concrete example could help speed up the discussion below.

On the other hand, it may prematurely constrain peoples’ thinking about it. So don’t get too attached to your first implementation. Maybe even keep the implementation to yourself until you feel the discussion could go faster if people saw it.

3. Advocate the feature

Think about the following questions and provide answers for them. Or find somebody who cares about the feature enough to advocate for it.

1. What problem does the proposed feature solve?

2. Who are the stakeholders? Who is going to benefit/be affected by this feature: end-users, repo farms like patch-tag, darcs developers?

3. Who are the users? New users? Repository maintainers? Patch authors?

4. What are the user scenarios?

5. Does this change any pre-existing workflows? Does this introduce any incompatibilities?

6. How do we preserve the conceptual integrity of Darcs? Is the UI for this feature really Darcs-ish?

7. What are the possible unintended interactions with other pre-existing features?

8. What are the alternative approaches to solving the same problem? Why do we prefer this one?

4. Find a skeptic

Find somebody to challenge the feature. Ideally, it would be somebody who does not like the feature. Expect them to challenge you on your answers to this discussion.

Remember that we’re all after the same thing here: a powerful and easy to use version control system, so getting challenged on the UI is a good thing. If we have trouble finding somebody to act as a skeptic, as a last resort, we can probably find somebody neutral/friendly to play the user advocate. It’s about Thinking, not Process.

5. Discuss

Attempt to reach consensus on how to move forward. As a last resort, ask for somebody to moderate.