Practical Mechanisms for Implementing Extended Backward Compatibility for Programming Languages, Libraries, and Data

This version refines the practical realization of Extended Backward Compatibility (EBC). In particular, the mechanisms for library version detection and name conflict resolution have been clarified and simplified by introducing two distinct, mnemonic functions. The overall structure and conceptual framework remain unchanged. In An Extended Notion of Backward Compatibility [1], backward compatibility was redefined as the existence of a formal, algorithmically specified transformation between versions of software artifacts. This interpretation allows compatibility to be treated not as an informal convention or a collection of ad hoc engineering practices, but as a precise and verifiable property of a system.In the present work, practical mechanisms for implementing Extended Backward Compatibility (EBC) are proposed for the main types of information used in software systems: programming languages, libraries, and data. It is shown that for each of these cases, simple and unified technical solutions can be introduced that ensure unambiguous version identification, conflict resolution, and controlled evolution of syntax and semantics. The implications of adopting EBC requirements for the long-term evolution of programming languages and software ecosystems are discussed.