Worked on the PyPSA/pypsa-eur repository, focusing on improving the stability and maintainability of the build workflow rather than adding new features. Addressed a bug by removing a duplicate input_profile_tech function in the build_electricity.smk file, consolidating logic to ensure a single source of truth and prevent configuration conflicts. This code refactoring effort reduced the risk of inconsistencies across clusters and streamlined debugging. Utilized Python and Snakemake for debugging and disciplined version control, demonstrating attention to code hygiene. The work contributed to more reliable energy-system modeling pipelines and lowered maintenance overhead by eliminating sources of drift in the workflow.