Contributed to the kanisterio/kanister repository by implementing support for an ignore rules file in the snapshot creation process. This work introduced a new --ignore-rules-file flag to the kopia snapshot create command, enabling users to specify files to exclude during backups based on custom rules. The development involved updating command-line interface arguments, modifying snapshot creation logic, and expanding test coverage to ensure compatibility with existing workflows. Using Go and backend development skills, the changes improved backup efficiency and policy control without introducing backward-compatibility issues. The approach emphasized test-driven development and adherence to code quality and sign-off practices throughout the process.