This keynote was presented at the 35th International Conference on Software Engineering (ICSE 2013) and was published by IEEE Computer Society Press.
In 2006, Ultra-Large-Scale Systems: The Software Challenge of the Future (ISBN 0-9786956-0-7) documented the results of a year-long study on ultra-large, complex, distributed systems. Ultra-large-scale (ULS) systems are socio-technical ecosystems of ultra-large size on one or many dimensions: number of lines of code; number of people employing the system for different purposes; amount of data stored, accessed, manipulated, and refined; number of connections and interdependencies among software components; number of hardware elements to which they interface. The characteristics of such systems require changes in traditional software development and management practices, which in turn require a new multi-disciplinary perspective and research. A carefully prescribed research agenda was suggested. What has happened since the study results were published? This talk shares a perspective on the post study reality---a perspective based on research motivated by the study and direct experiences with ULS systems.