Large software projects are among most sophisticated human-made systems consisting of a network of interdependent parts. Past studies of software systems from the perspective of complex networks have already led to notable discoveries with different applications. Nevertheless, their comprehension of the structure of software networks remains to be only partial. They here investigate correlations or mixing between linked nodes and show that software networks reveal dichotomous node degree mixing similar to that recently observed in biological networks. They further show that software networks also reveal characteristic clustering pro les and mixing. Hence, node mixing in software networks significantly differs from that in, e.g. the Internet or social networks.