the lab
?open question

Are you the user?

When you build a tool for yourself, how do you tell whether the design generalizes — and does it matter?

October 8, 2025 ↳ margin

The most honest version of this question, asked of me in a kitchen by a friend who doesn’t work in software:

“If you only ever build it for yourself, isn’t that just journaling with extra steps?”

I don’t have a good answer yet. The candidates I’ve considered:

  • It does generalize, eventually, if the self is honest. This is the romantic version. Bret Victor and Andy Matuschak both work like this. But survivor bias is doing a lot of work in this argument.
  • It doesn’t have to generalize. A tool used by one person, well, is not a failed tool. It’s a garment. We don’t ask shirts to scale.
  • It generalizes through the artifacts it produces, not through the tool itself. This is the version I most want to be true. The tool is a means; the essays and the prototypes are the public good.

I keep circling back to the third — but I don’t yet have a good test for when it’s a rationalization.

Related: the methodological aside in A reader's stance.