Worked on build systems and configuration improvements across two repositories, focusing on reproducible builds and codebase standardization. In the biomejs/biome repository, updated the Rustfmt configuration to align with the 2024 edition, ensuring consistent Rust code formatting and reducing future maintenance overhead. For gitlabhq/gitlab-shell, enhanced build reproducibility by modifying the Makefile to honor SOURCE_DATE_EPOCH, resulting in deterministic build artifacts and improved auditability across environments. Leveraged Shell scripting and TOML for configuration management, with an emphasis on reproducible builds and CI/CD reliability. The work addressed maintainability and reliability, delivering targeted features without introducing or resolving bugs during the period.