Mapnik
Mapnik is an open-source toolkit for developing mapping applications. It can be used for both desktop map design and web development, and provides algorithms and patterns for spatial data access and visualization.
Mapnik itself is not a Mapbox product, but Mapbox engineers contributed to the project and it was used in several legacy Mapbox products. For example, Mapnik was used to render tiles from classic styles, and was also used to render maps within Mapbox Studio Classic.
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