As the time went on ParcPlace and IBM sold their product and the new releases become almost incompatible with our codebase. And then, and this was really worse, both Smalltalk products didn?t run on newer operating systems (we have used Linux and Windows NT).
We have rewritten the Code, in C. Since then not only have we got a performance plus of one order of magnitude, no, portability to some useful extend is granted. Our oldest, still used, C project were built about 20 years ago and still compiles today.