The common issue of software working on a developer's machine but failing elsewhere signifies an architectural problem. This occurs because crucial parts of the system's behavior are not captured in version control, making the developer's workstation an implicit, undocumented dependency. Differences in runtime versions, CPU architecture, filesystem, locale, time zones, native libraries, certificates, environment variables, dependency resolution, or build tooling can all cause these failures. These discrepancies mean the system lacks a complete and reproducible definition of its build and run conditions. Reproducible-build practices aim to solve this by ensuring declared sources and inputs lead to verifiable artifacts. Currently, repositories often hold source code and configuration but exclude operating assumptions. For instance, different Java Development Kits can alter a service's behavior. Code relying on the host's time zone can produce varied results due to variations in the Java Virtual Machine's runtime environment. Similarly, the default locale, which influences locale-sensitive operations, can be inherited from the environment, leading to inconsistent outcomes.