"Works on My Machine" Is an Architecture Problem

The familiar claim that software behaves correctly on a developer workstation but fails elsewhere is often treated as a debugging cliché. In practice, it describes an architectural failure where part of the system’s behavior exists outside version control. Source code may be identical while the effective execution environment differs in runtime version, CPU architecture, filesystem semantics, locale, time zone, native libraries, certificates, environment variables, dependency resolution, or build tooling.