sum of the parts

working with a new development team on a business app to be surfaced through a portal. taking them through an agile project approach. spent the past few weeks doing:

  • domain modeling
  • feature list elicitation
  • looking at the technical architecture (the “how”)
  • UI sketches

We then did a first pass at estimating the features… An estimate of how long it would take to build the feature — including everything from persistence to surfacing it on the UI and all parts in between.

“But do we need to estimate building the UIs too?”

That’s a good question. I explained that there were lots of features that contribute to a given UI screen… Therefore, there were lots of “pieces” of estimates from each of those features to be built. These piece-wise estimates of the UI will ultimately contribute to enough hours for the overall UI screen. I think of it as a bottom-up approach to getting a reasonable estimate going.

You can also look at a UI design and estimate it top-down. Check the two against each other if you like…

Not to say that we won’t also have some specific UI work. Just that we do not need to count the full cost of building the feature *and* the full cost of building the UI.

How do you estimate?