From time to time I have the chance to work with 
PyCairo, the Python bindings to the 
cairo graphic library. I appreciate this library because it allows to draw graphics primitives so super fast and thus it is very suitable to use it in web projects.
After my trials with 
GRASS GIS as WMS backend I thought I could create a raster web map service with improved performance by using PyCairo instead of GRASS GIS as renderer.
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| Zoom in - it is a super fast WMS! |