The author of this paper is a strong supporter of the view that systems should be developed as formal specifications, that system modifications should also be first introduced in specifications, and that programs should be generated from specifications by means of transformations. The purpose of the paper is to demonstrate the effectiveness of an interactive rule-based expert system approach to the transformational process.

The example presented is a package routing problem that is first specified in the language Gist. The specification is then transformed semiautomatically into a LISP program by means of the Glitter transformation system. Gist and Glitter have been in use for some time. Thus, the author’s main contribution seems to be the extension of the knowledge base of Glitter to the point that 90 percent of the problem development steps can be performed by the system, and only 10 percent require user intervention. A question remains: To what extent is the knowledge base of Glitter geared to the specific requirements of the package routing problem? Note also that reference [14] of the paper is missing.