paul goullencourt
GIS engineer on the Tesmo Maps project for the past year. I am passionate about data visualisation and cartographic rendering, with a particular interest in open-source tools and the possibilities they offer for working with OpenStreetMap data. As the OSM specialist within my organisation, I also actively contribute to OpenStreetMap, with a focus on railway data
paul_sncf_connect
Session
OpenStreetMap is one of the richest databases in the world. state of the map
whenever it comes to creating a vector base map, we all run into the same wall: the daunting complexity of MapLibre/Mapbox GL style files. The result? We tend to fall back on "off-the-shelf" styles or minor variations, smoothing over the semantic richness of the underlying data.
As a GIS engineer at Tesmo Maps / SNCF Connect, I had to rethink my methods to stop being held back by my tools. In this talk, I share my hands-on experience building an industrial-grade workflow to regain full control over map rendering:
- Style-as-Code: Why and how I moved away from visual editors (such as Maputnik) to work directly with JSON in a text editor.
- The "Live Edit" workflow: A walkthrough of my toolstack — simple, reproducible, and built entirely on open-source components.
- The Design/OSM translator: My method for collaborating with designers who have no background in geography or the OSM data model, and turning their creative intentions into complex technical filters.
The goal is to show that anyone can build and maintain a large number of fully custom styles.