Andrew Garrett focused on enhancing configuration resilience for both the google-gemini/gemini-cli and zed-industries/gemini-cli repositories by implementing backward-compatible migrations for user settings. He addressed the migration of legacy allowedTools properties to the updated tools.allowed structure, ensuring that user configurations were preserved during upgrades. Using TypeScript and full stack development skills, Andrew developed and tested migration logic that maintained workflow continuity for users who had not updated their settings. His work included comprehensive test coverage to validate correct behavior, reducing upgrade friction and improving reliability. This targeted engineering addressed two critical bugs and strengthened the overall upgrade process.