Problem: configure: error: could not find libxml2
Solution: sudo xcode-select -s /Library/Developer/CommandLineTools
Problem: configure: error: could not find geos-config within the current path. You may need to try re-running configure with a --with-geosconfig parameter
Solution: brew install geos
Problem: configure: error: could not find proj_api.h - you may need to specify the directory of a PROJ.4 installation using --with-projdir
Solution: brew install proj
and then CFLAGS=-DACCEPT_USE_OF_DEPRECATED_PROJ_API_H pex install postgis
Problem: configure: error: gdal-config not found. Use --without-raster or try --with-gdalconfig=
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