During June 2026, contributed to both the Prometheus and rclone repositories by delivering targeted improvements focused on security and reliability. In Prometheus, upgraded the rule group pagination token generation from SHA-1 to SHA-256, enhancing cryptographic security while maintaining API compatibility and adding unit tests to ensure token determinism and format correctness. For rclone, addressed a PowerShell completion bug by enforcing UTF-8 encoding, preventing non-ASCII path corruption during tab completion. Work emphasized robust API development, CLI tooling, and comprehensive testing in Go, with careful attention to backward compatibility and regression safety across both projects, supporting ongoing developer skill growth and user experience.