Programming · Blog · 🇬🇧 United Kingdom
Converting Map Data with AI's Help
Simon Willison used Claude and ChatGPT to convert a shapefile of a park boundary into GeoJSON.
- Profession
- Developer, GIS Analyst
- Source
- simonwillison.net ↗
- Country
- 🇬🇧 United Kingdom
- Report date
- March 22, 2024
- Verified on
- October 24, 2026
What they did
He asked the AIs for the commands to convert and simplify the file.
How it went
The account gives no numbers.
Good to know
Check the result on a map.
The prompt
I have a shapefile [description/projection]. Give me the command (ogr2ogr or Python) to convert it to WGS84 GeoJSON and simplify the geometry, and how to check it on geojson.io.
Replace what is in [brackets]. Prompt written by us from the account, not a literal copy of the source. Do not paste other people’s personal data (privacy laws such as LGPD and GDPR apply).
Summary in our own words. Results as stated in the original account; we have not tested or audited them. Read the source ↗ Found a mistake?
Similar cases
01Teaching an agent to use your bank's API
A developer created an open source skill so Codex and Claude Code can integrate with the Banco Inter API.
02Finding a strange bug by pasting the error into ChatGPT
A Java dev couldn't create a table in H2; ChatGPT pointed to the problematic field.
03Letting the agent deploy and read production errors on its own
The founder of a deployment platform explains how they designed an MCP server to take the human out of "copy and paste the log".
04Launching a habit app solo and doing the marketing with AI
A dev created Kada, a habit app with no account and no ads, and used AI for marketing.
05Building an "internet TV" in 6 days with a team of agents
A dev created Crom TV, with 24-hour channels of YouTube videos, coordinating several AI agents.
06Asking AI for a specific algorithm for a research project
A developer skeptical of LLMs used Gemini to generate random quantum circuits in the QCOP project.
07Set up a 100% local AI coding environment
A junior developer integrated local models into VS Code with Ollama and Cline, with no paid APIs.
08Build a World Cup tracking website with AI help
An engineer built Central da Copa 2026 and explains why it wasn't "just asking the AI to do it."