Backward compatibility

Backward compatibility ensures new versions of products continue supporting older implementations, data formats, or integrations. This principle protects users who can't immediately upgrade due to budget constraints, legacy systems, or organizational approval processes.

Breaking backward compatibility creates accessibility barriers. Users in developing markets often rely on older hardware that can't run the latest software versions. A banking app requiring the newest OS version effectively excludes customers who need financial services most.

Companies must weigh innovation speed against the real cost of forcing upgrades on vulnerable populations. Strategic compatibility decisions balance technical debt against user impact. Maintaining legacy support indefinitely becomes unsustainable, but phasing it out requires careful planning. Provide clear migration paths, maintain parallel systems during transitions, and offer extended support for critical use cases.