we have multiple clients with different needs. Although our software is modularized to a degree, it's almost certain that we need to adjust every module's business logic here and there a little for each customer. The changes are probably too tiny to justify splitting the module into a distinct (physical) module for each client, I fear problems with the build, a linking chaos. Yet, those changes are too large and too many to configure them by switches in some configuration file, as this would lead to problems during deployment and probably a lot of support troubles, especially with tinker-type admins.
I'd like to have the build system create multiple builds, one for each client, where changes are contained in a specialized version of the single physical module in question. So I have some questions:
Would you advise letting the build system create multiple builds? How should I store the different customizations in source control, svn in particular?