A compendium of formal techniques for software maintenance

Software maintenance is an important area in practical software engineering that has been largely overlooked by many theoretical computer scientists. This paper gives an overview of some formal techniques that have been developed recently to aid the software maintenance process, and in particular reverse engineering and re-engineering. In the future, it is suggested that speci cations rather than programs should be maintained. The work described provides a mathematical basis to a large collaborative project that has been investigating many other aspects of software maintenance as well.