Kitchens are like software: a good design is crucial

We needed to design our new kitchen.

Design is a process of making choices, removing ambiguity, and getting specific. Which cabinets would we use, where would they go, and how would they fit with the appliances? What sort of doors, handles, shelves, knobs, and racks would go in the cabinets? What material should be used for the countertop (we chose a lovely piece of "Tropical Green" granite), and what size and color should it be?

Several early design decisions were crucial:

• Since the granite countertop was the most important part of the upgrade, everything else had to work with it. The counter was to be large and striking, the centerpiece of the new kitchen.
• To increase overall storage space, we decided to make the counter extra-large, and install a second set of base cabinets on the "far side" of the counter, with an overhang so people didn't bump their feet on them when sitting at the counter.
• We would use IKEA cabinets.

IKEA provides software for kitchen planning, downloadable from their web site. It's quite powerful software, with tools for selecting different cabinets in different styles, arranging and assembling them into position, and presenting you with a 3-D view of the resulting kitchen, with a fly-through feature so you can zoom in-and-out and walk around in your new simulated kitchen. Unfortunately the software crashed routinely on my main computer, but it worked reliably on another computer so we used it there.

There are lots of hidden features within the IKEA planning software, which the IKEA employees are all aware of. So we took advantage of the feature that let us save our in-progress design to the IKEA web site, then we travelled to the store and opened the design at the IKEA planning booth inside the store, and various IKEA employees helped us improve and refine our choices.

We spent many, many hours with that IKEA planning software. I have no idea how hard it would have been to communicate our design desires to our contractors without it.

After we reached a design we were comfortable with, the planning software printed out a complete bill of materials, with every last panel, door, handle, and accessory listed, and gave us an extremely detailed price quote that we were able to use for our final budgeting and adjustment. And when we actually ordered and paid for the cabinets, we simply opened our saved kitchen design at the IKEA planning booth, and the IKEA employee activated the order.

Software design has lots of design tools, too: there are word processors, sketching and storyboarding tools, diagramming tools, rapid prototyping systems, and so forth. I use these tools quite frequently during software design, but I find that a major part of software design is the identification and clarification of constraints. There are usually some major constraints that govern the implementation of software systems, and elaborating and achieving agreement on these constraints is a crucial component of design. Constraints are typically restrictions on the software's behavior, for example:

• All data must be tracked in such a way that a historical audit trail, showing all incremental changes over time, can be produced on demand,
• The system must be deployable on a low-end laptop with 1 GB of physical memory, for demonstrations and early use, but must scale up to fully utilize 32-way server systems with 64 GB of memory.
  

As the design starts to emerge, I try to capture the most important choices and decisions and invariants in writing, so that we can all agree on them.

It would be great if there were an IKEA planning tool for server software design; maybe one day I'll see such a thing!