Simon Willison vibe-codes a GeoJSON map tool, with ChatGPT Work pulling government boundary data
MaxLenormand · x · 2026-09-02
Simon Willison shipped a small vibe-coded GeoJSON Map Viewer: paste GeoJSON, adjust fill color/opacity, render on OpenStreetMap, export PNG — faster than hunting for an existing tool.
The reusable workflow:
- Ask ChatGPT Work for boundaries of almost anything and it extracts and combines files from government data sources (e.g., "exact boundary of El Granada GCSD"), producing ready-to-use GeoJSON;
- Iterate with Claude Code for web and Fable 5.1 to finish the tool.
Quoter MaxLenormand adds a corollary: we now all build many small local tools that never get published, so the most helpful thing is sitting down in person to see what others are building.
More from coding & agent
- Merge launches enterprise AI governance tool enforcing model routing and spend rules — shensi · 2026-09-02
- Weaviate Ask Mode Adds Configurable Evaluation to Trade Latency vs Verifiability — CShorten30 · 2026-09-02
- Building the Ultimate Agent Harness for Kimi K3: The Model Is No Longer the Bottleneck — VibeMarketer_ · 2026-09-02
- GLM 5.2 slug references spotted in Google Antigravity CLI, hinting at integration — gaganghotra_ · 2026-09-02
- Design lead ships 12 PRs in a week: AI is erasing the designer-engineer gap — talkaboutdesign · 2026-09-02
- Measuring MCP servers: 78% of fixed token cost comes from tool schemas — Lexeik · 2026-09-02