During the month, contributed security-focused enhancements across the sublime-security/sublime-rules and sublime-security/static-files repositories. Expanded impersonation detection by adding capitalonetradecredit.com to domain-based rules, increasing coverage for Capital One Trade Credit and strengthening threat detection. Improved email deliverability by including deluxe.com as a high-trust sender root domain, refining trust signals for inbound communications. Leveraged YAML for configuration management and domain analysis, ensuring changes were robust and maintainable. Collaborated across repositories to extend security posture and reduce risk, focusing on precise rule updates rather than bug fixes. The work demonstrated a methodical approach to security engineering using text-based configuration and threat detection.