Review on Mapnik by Darrell Shreves

I like that it's open source so you can see how everything works behind scenes (it is not just magic). It also has good support for GIS data formats such as shapefiles or GeoJSON files from ESRI/QGis etc., which makes integration easy if your organization already uses those file types. The documentation could be better but there are many online resources to help out when getting started using this library. If you're looking into mapping services then look at other options because they tend towards proprietary software whereas Open Source solutions have more flexibility around licensing issues - especially regarding use of their service outside North America where some companies may require an additional license fee per user / country. We were able solve problems related specifically to our business needs by utilizing geospatial analysis capabilities within Qgispy via python scripting language. This allowed us access all relevant information we needed about customers' businesses without having them send over.