The Best Place to Build a Subway

Many engineering projects are big and complex. They require integrating into the existing environment to tie into stuff that precedes the new, big, complex thing. It is common to bemoan the challenges of dealing with the preexisting stuff. Many times, engineers don't realize their projects (and their paychecks) exist only because of the preexisting and complex systems that impose constraints on the new work.

This column looks at some sophisticated urban redevelopment projects that are very much part of daily life in San Francisco and compares them with the challenges inherent in building software.