Worked on optimizing repository rule fetch performance in the JetBrains/rules_python project, specifically addressing inefficiencies related to PATH-change scenarios. Developed a solution in Python that modified the _which_unchecked function to avoid unnecessary re-fetching of repository rules when the system PATH changes, only triggering PATH monitoring in failure cases. This approach reduced redundant operations and improved resource usage, resulting in faster rule resolution and smoother workflows for developers working with PATH-sensitive configurations. Leveraged expertise in Bazel, Python development, and repository management to deliver a targeted bug fix that enhanced both the efficiency and stability of the development and CI environments.