We change the search procedure so it detects NixOS from /etc/os-release and uses "libnuma.so" when calling dlopen, instead of harcoding a full path to /usr. The full patch of libnuma is stored in the runpath, so dlopen can find it.
It tries to dlopen libcrypt.so.1 and libstdc++.so.6, so we make sure they are available by adding them to the runpath.
