The International Workshop on Software Engineering for Systems-of-Systems and Software Ecosystems (SESoS) series was established in 2013 as the first scientific forum to address systems-of-systems (SoS) from a Software Engineering perspective. This paper summarizes a study of the evolution and future trajectory of Software Engineering for SoS by analyzing 64 papers published across 12 editions of SESoS (2013–2024). The study combined scoping review and scientometric analysis to categorize and evaluate contributions based on temporal and geographic trends, key research topics, methodologies, application domains, and research impact. From these insights, this paper also sheds light on advancements and explores current and future research directions in Software Engineering for SoS.