Fixing things that can never be broken: Soware maintenance as heterogeneous engineering

In the very last published article of his long and distinguished career, the eminent historian of computing Michael Mahoney asked a simple but profound question: “What makes the history of soŸware hard?’’ In his characteristically playful style, Mike was engaging both with an issue of central importance to historians – namely, how can we begin to come to grips with the formidable challenges of writing the history of soŸware – but also one of great interest to practitioners. Since the earliest days of electronic computing, the problem of soŸware has loomed large in the industry literature. e history of soŸware is hard, Mike argued, because soŸware itself is hard: hard to design, hard to develop, hard to use, hard to understand, and hard to maintain. is paper focuses on the problem of maintenance in the history of soŸware. As all of the papers in this session argue, the problem of maintenance is a ubiquitous but neglected element of the history of technology. All complex technological systems eventually break down and require repair (somemore so than others), and, in fact, as David Edgerton has suggested, maintenance is probably the central activity of most technological societies. But maintenance is also low-status, di›cult, and risky. Engineers and inventors don’t like maintenance, and generally don’t do maintenance, and therefore historians of technology have largely ignored it. e problem ofmaintenance is particularly challenging for the both practitioners and historians of computing. To begin with, in theory soŸware should never need maintenance. SoŸware does not break down or wear out, at least in the conventional sense. Once a soŸware-based system is working, it will work forever (or at least until the underlying hardware breaks down – but that is someone else’s problem). Occasionally a stray cosmic ray might žip an unexpected bit in a soŸware system, causing an error, but generally speaking, soŸware can never be broken.