Libfontconfig.so

When trying to build rust gui applications I get the error ‘error while loading shared libraries: libfontconfig.so.1: cannot open shared object file: No such file or directory’
I have pkg-config and fontconfig installed and have tryed building using:

nix-shell -p pkg-config fontconfig freetype ftgl gperf pkgconf expat 

But still no luck…
Does anyone know how to solve?