The virtualization and softwarization of network functions is the networking industry's latest achievement. Software-Defined Networks (SDN) and Network Function Virtualization (NFV) propose novel software architectures and development process adapted to for instance mobile networks (e.g., 6G). However, these architectures and processes are mainly defined by the telecommunications community, without much regard for the contributions of software engineering to generic software processes. This paper explores how the fields of software engineering (SE) and telecommunications can work together to improve service virtualization, cloud computing, and edge computing in the context of next-generation networks. It also highlights the potential of SE fields like software architecture, variability, and configuration to greatly enhance the development of virtual network functions (VNFs). On the other hand, the new contributions should be energy efficient, since this is a primary goal in next-gen networks. Finally, current software processes should consider the impact of communication networks on the correct functioning of software products, since network functioning can affect the QoE of users.