Browser Security Engineer, Perplexity AI

• Prior experience in browser, application, or product security (ideally with Chrome/Chromium or other browser engine experience)
• Deep knowledge of modern browser architectures; understanding of XSS, CSP, sandboxing, extension security, and WebView-specific threats
• Experience with security reviews and threat modeling for web, mobile, and extension platforms
• Ability to work cross-functionally with engineers, product leads, and external security researchers

Desirable

• As Comet continues to grow as a stand-alone product and codebase, we are seeking a Browser Security Engineer to lead and own browser-specific security initiatives, including custom Chromium development, extension security, and cross-device features
• Browser/Chromium Security: Browser security encompasses threats and vulnerabilities (e.g., XSS and Same-Origin Policy issues)
• Custom Engineering: The Comet product features substantial custom work, including our Chromium fork, browser extensions, and secure sync features between devices
• Proactive Partnership: As Comet’s complexity grows, a dedicated security engineer embedded with the product team will enable us to proactively identify and address concerns—well before red-teaming or external audits
• Lead threat modeling and security architecture reviews for all Comet browser surfaces
• Collaborate closely with product and engineering teams to proactively identify and mitigate browser vulnerabilities, especially issues specific to custom Chrome engineering and browser extension architecture
• Develop security best practices, tooling, and documentation for engineers building browser-facing features
• Serve as the security expert for topics such as Same-Origin Policy (SOP), XSS, sandboxing, browser extension permissions, and secure inter-device communication
• Triage and resolve vulnerabilities found by external researchers (e.g., bug bounty, red-teaming partners) and the Chromium community
• Build strong relationships with security partners and leverage their feedback for continuous improvement
• Stay up to date on emerging browser security threats, tools, and industry trends