The present invention provides a system and method of using highly structured program testing, regression testing, final test and fix procedures and commit procedures at the levels of the Business Unit, at an intermediate pre-integration branch level and finally at a primary technology branch of the current IOS source code system before final system testing is performed as an antecedent to a regular release of a new version of the IOS regularly, approximately every 8 weeks. New features and functions are accommodated in this 8 week release cycle by a process of alternating "fat" and "thin" releases which contain many and few new features respectively. Moreover, in the preferred embodiment which incorporates this rigorous process, no more than three generations of the main branches of the IOS source code are maintained at any one time.