Div Mehta enhanced the build configuration system in the smithy-lang/smithy repository by implementing multi-variable expansion for inline variables. Using Java and advanced regular expressions, Div refined the parsing logic to support robust substitution of multiple variables, including both environment and user-defined variables, within configuration strings. The solution included a comprehensive test suite to verify correct expansion behavior and prevent regressions, aligning with continuous integration requirements. This work improved the reliability and consistency of build processes by reducing misconfiguration risks. Div demonstrated depth in build system configuration, regex-based parsing, and test-driven development, delivering a focused and maintainable engineering solution.