I disagree about the concept being broken: CPAN and Gems work on similar principles, except that the download step is reserved for a human running an explicit i

I disagree about the concept being broken: CPAN and Gems work on similar principles, except that the download step is reserved for a human running an explicit installer program. Add a filesystem cache and some digital signatures, i.e. an offline mode and some way of declaring "I expect this module to be signed with this trusted RSA key", and I think it would be workable.