This case study tells the story of the development of a critical IT system within an executive department of the U.S. federal government, using iterative, Agile, and Lean development methods and cloud-based technologies. This study reports the successes and challenges of using this new development approach in a government software development environment so that other government entities can benefit from the experiences of this project. The study is based on conversations with team members, observations of team activities, and examination of work products, documentation, and program guidance. The report describes the organizations responsible for creating the software solution, establishing the development process, and structuring acquisition activities. It then details the product development process in chronological order and describes the development approaches and technologies. It also puts events into the context of external environmental influences to present a development effort as it confronts real-world challenges. The final section describes insights gleaned during the research of this case study and includes analysis of the organization’s experiences with Agile and Lean adoption, technical approaches, and project leadership. These insights may benefit future Agile projects in the federal government and the software engineering community as a whole.