Developed a targeted security safeguard for the LedgerHQ/actions repository by implementing a kill switch in the GitHub Actions CI pipeline to address a supply chain incident. The solution, built using JavaScript and YAML, temporarily disabled Spectral CLI installation, enabling rapid containment and supporting incident investigations while maintaining the option for controlled reactivation. This approach emphasized security management and CI/CD best practices, ensuring that changes were explicit and auditable through traceable commits. The work prioritized minimizing production risk and preserving workflow stability, demonstrating a methodical response to supply chain threats within a DevOps environment focused on robust, security-first automation.