Fiona and Rasterio are new GDAL-based Python libraries that embody lessonslearned over a decade of using GDAL and Python to solve geospatial problems.Among these lessons: the importance of productivity, enjoyability, andserendipity to both experts and beginners.I will discuss the motivation for writing Fiona and Rasterio and explain howand why they diverge from other GIS software and embrace Python's native types,protocols, and idioms. I will also explain why they adhere to some GISparadigms and bend or break others. Finally, I will show examples of using Fiona and Rasterio to read, manipulate,and write raster and vector data. Some examples will be familiar to users ofolder Python GIS software and will illustrate how Fiona and Rasterio let youget more done with less code and fewer bugs. I will also demonstrate fun anduseful features not found in other geospatial libraries.