Deeper SAST expands the capabilities of Sonar's SAST to help detect more security vulnerabilities in JavaScript or TypeScript applications by considering interactions with third-party, open-source libraries. Traditional SAST scans application code but lacks understanding of dependencies, while Deeper SAST pre-scans popular libraries to find sources and sinks, enhancing Sonar's taint analysis engine to uncover hidden vulnerabilities. This improves the detection of injection attacks and other security issues, promoting Clean Code and secure development practices.