There is Guillermo Iguarán who contributes to Rails. I personally have contributed to several large geospatial projects like GeoNode / GeoServer and Inasafe and bits to other projects like Django/GeoDjango in the past.
In retrospect I should have used a different term to differentiate people that are sharing smaller projects with liberal licenses from people who regularly write patches for the linux kernel.
In retrospect I should have used a different term to differentiate people that are sharing smaller projects with liberal licenses from people who regularly write patches for the linux kernel.