I am not a big fan; one advantage that I see in Guix over Debian is that when I install a C library, I immediately can work with it in a development context. Just "gmp", not "libgmp" and "libgmp-devel". And there would be a lot of duplication in defining packages: When now we have gmp as an input, we then would need gmp:out as an input and gmp:dev as a native-input.
Andreas
