Mark IV: evolution of the software product, a memoir

The article describes the story of the evolution of an early commercial software product, Mark IV, from preconception through its early trials and tribulations to its realization. The goal was not always clear, the path was not always direct, but we got there. In 1965, the Mark IV file management system was conceived as a non application oriented software product, the first true such software in the field. It was designed to run on all IBM 360s but was never truly successful on the smallest ones. The suggested price was agreed at $30000