How to develop and maintain 1 million lines of code in the SWMF

Presentation given by Gabor Toth at the Developing Heliophysics Standards and Cross-Science Collaborations Workshop on Aug 11, 2025. SWMF = Space Weather Modeling Framework. The presentation discusses the challenges and successful approaches to maintain a large code base actively developed by many people. Use of proper software engineering, including version control, testing and coding standards are emphasized.