Mapnik

Mapnik is an open source mapping toolkit for desktop- and server-based map rendering, written in C++.

One of its many users is the OpenStreetMap project (OSM), which uses it in combination with an Apache Web Server module (mod_tile) and openstreetmap-carto style to render tiles that make up the OSM default layer - Mapnik

Artem Pavlenko, the original developer of Mapnik, set out with the explicit goal of creating beautiful maps by employing the sub-pixel anti-aliasing of the Anti-Grain Geometry (AGG) library - wikipedia

Mapnik now also has a Cairo rendering backend. For handling common software tasks such as memory management, file system access, regular expressions, and XML parsing, Mapnik utilizes the Boost C++ libraries.

An XML file can be used to define a collection of mapping objects that determine the appearance of a map, or objects can be constructed programmatically in C++, Python, and Node.js

Mapnik is a cross platform toolkit that runs on Windows, Mac, Unix-like systems like Linux and Solaris (since release 0.4) - wikipedia