Planning the Reengineering of Legacy Systems

24 reengineering project depends to a great degree on proper planning. It is not easy to upgrade and migrate several hundred programs and databases without disrupting data-processing service. It is also not easy to justify such a project. Management must be convinced that the organization is really going to achieve a significant benefit in reduced costs and added value. Considering the fact that the functionality of the software remains unchanged, this requires an in-depth analysis of the expected quality and productivity increases. Maintenance metrics are required to measure the improvements. I have been a programmer for more than 25 years, so I have great respect develop and prove good software. There is, no doubt, a great need to improve the quality of existing software products and processes. One way to accomplish this is through reengineering. Reengineering poses its own technical challenges transforming the language, extracting objects, reallocating functions, and proving the equivalence of functionality. However, the overriding business issue is whether reengineering is worth the effort or if legacy systems should be replaced with new ones. It is this question I address here.