We built etter, an open-source Python library that turns natural language location descriptions into spatial filters. You give it "north of Lausanne" or "on the shores of Lake Geneva" — it gives you a GeoJSON geometry your app can use directly. It's LLM-agnostic, multilingual, and handles the kind of spatial nuance that breaks naive approaches. If you build location-aware products, you'll want to read this.

Since 2019, Camptocamp supports the Agence du Numérique de la Sécurité Civile (ANSC) in the development of NexSIS, the information system for firefighters and civil security, now in production in 20 Fire and Rescue Services (SIS).

This post is about lifting the curtain on how Geo Challenge was designed and built—and the technical choices that went into it.