One of the most impactful decisions that most of us will make is whether to replace a creaking software system with something new, or whether to iteratively improve the current system. Either choice is generally a significant investment. Spoiler: the answer (as with so many other questions that come to a staff engineer) is ‘it depends'.

This talk explores the technical, organizational, cultural, and psychological factors that matter when we choose between full rewrites or incremental change.