Worked on the mozilla/gecko-dev repository to enhance content security policy (CSP) reliability by developing targeted test coverage for hash-based evaluation of script sources. Focused on implementing CSP Eval Hash Handling Tests, the work validated that scripts with specific eval hashes are correctly allowlisted while ensuring that unsafe-eval is blocked when hashes are present. Leveraging JavaScript and HTML within the Web Platform Testing framework, the developer expanded the test suite to exercise nuanced CSP hash logic. This approach improved early detection of policy regressions in continuous integration, aligning with security goals and providing clear traceability from code changes to policy behavior.