We are entering the age of just-in-time software. Some of my coworkers are visiting San Francisco this week, so I asked Claude Fable to design an extremely detailed HTML map of San Francisco so I can explain the city to them.
The HTML is wild. It has all the street names, their exact dimensions, the relief of the city, the fog, the sun exposure etc.
Everything it real. I was super surprised but it went and found the city's actual data, then built a cartographic engine around it. So I have:
- Every street from the SF Public Works centerline survey: 15,905 segments, 2,502 named streets, 54,989 surveyed vertices, with the official address ranges per block
- The relief from 14,151 municipal elevation contour points, interpolated into a 168,000-vertex terrain model
- 9,672 buildings with lidar-measured heights from an SF Planning study
- Every Muni Metro line, the cable cars and BART from the official GTFS feed: real route shapes, real 10-minute headways, real speeds. 76 little trams move on the map at their scheduled pace, and the K dims when it passes under 175 meters of Twin Peaks because it knows the tunnel portals (wtf!)
- Fog modeled as marine-layer advection over the terrain, calibrated on NREL satellite irradiance and a decade of ASOS weather observations.
Claude did totally overkilled stuff like the fog model's 50% line landed at longitude -122.437 which is... Divisadero Street (every San Franciscan knows the fog stops there)
The whole thing is one self-contained HTML file, 1.2 MB, with a WebGL engine. No libraries, no API calls, no network. It runs offline forever.
We talk about scaling and benchmarks all day. Sometimes the bitter lesson is simpler: give the machine real data and real verification loops, and it builds you the city.
I'm spending the evening exploring the map; it's too good!