Photos that erase themselves as you watch

Photos were out of scope from the start. An image gets stored, served, cached — and we store nothing.

We added them in the end, on one condition: that they behave like the rest of the bench. They live in memory for forty seconds, in the same process as the messages, without ever touching a disk. No file is written anywhere.

The destruction is visible

A photo is sharp for ten seconds. Then it pixelates for twenty seconds, coarser and coarser, until it's a handful of squares. Then it disappears, and the image is torn down for good.

We could have made it vanish all at once. Gradual degradation says something a sudden disappearance doesn't: it shows you time passing while it passes. You look at an image knowing it's dying, and that changes how you look at it.

The rest is technical common sense. The image is shrunk on your phone before it's sent — 1080 pixels on the long edge, never high definition. Re-encoding throws away the EXIF metadata on the way, and with it the camera's GPS coordinates. And only people sitting on the same bench can fetch the bytes.