What is styleglot?

Styleglot is a translator for digital map styles. The three major mapping platforms, Esri, Mapbox, and MapLibre, all use slightly different formatting rules for their visual styles (the files that tell a map what colors to use, where to place labels, and how thick to draw roads). If you build a map using one platform and want to switch to another, you normally have to rewrite your style files by hand. This library automates that process, instantly converting styles between any of the three formats. The tool works in three steps. First, it reads your original style file and translates it into a neutral, universal format. Second, it runs a series of checks and adjustments to make sure the visual rules make sense for the platform you are switching to. Finally, it outputs a brand new style file perfectly formatted for your target platform. It can automatically detect which format your original file uses, or you can specify it yourself. It also includes an asynchronous version that can fetch live map tile data from the internet if your style relies on external sources. A mapping team building a custom visualization on top of Esri's free basemaps might decide to migrate their entire project to an open-source alternative like MapLibre to save on licensing costs. Instead of manually recreating their custom road colors, text labels, and terrain shading in a new system, they can pass their Esri style file through this library and get a ready-to-use MapLibre file back in seconds. One important tradeoff is that not every visual feature exists in all three platforms. For example, Mapbox has special atmospheric effects like "fog" that Esri and MapLibre do not support. The library handles this gracefully by dropping the unsupported features, but it carefully tracks every omission and provides a list of warnings so you know exactly what did not transfer over. It also handles platform-specific quirks, like swapping out proprietary font names for open-source equivalents, and ensuring that private API keys are securely managed during the conversion.