A street screen that counts people without ever keeping a face
A portrait ad screen for small shopfronts. It measures the street: footfall, attention, rough age band. Only anonymous counts ever leave it. I designed and specified it for the retail-growth startup I founded, and built it with Claude Code.
What I decided
- Hardware designed in code. A parametric CAD model that will not export unless 33 checks pass: clearances, wall thickness, every part watertight.
- Thinner than the reference. 47 mm deep against the 61.6 mm panel it was benchmarked on, with separate cooling chambers for the computer and the display.
- Privacy as an engineering rule. Per-minute anonymous counts only. A test fails the build if any code path could write pixels.
- Didn’t settle for the stock model. It scored 79.5% on Indian adult faces, so I trained a replacement. It scores 99% on the benchmark.
Where it stands CAD complete · software verified in a simulator · first hardware trial next







