Senior Software Engineer (Browser Extension)

Cyberhaven is redefining data security by understanding how data flows across organizations. The Senior Software Engineer will build and enhance secure, performant browser extensions integrated with endpoint and backend systems, while improving reliability and supporting evolving browser platforms.

Responsibilities:

• Design, build, and maintain a robust browser extension for Chrome, Edge, and other major browsers using Manifest V3 and modern APIs
• Implement features that securely interact with web content and backend services, ensuring compliance with security best practices
• Optimize performance and reliability across diverse environments and user workflows
• Work closely with the endpoint agent and backend teams to ensure tight integration and consistent functionality across endpoints and services
• Stay ahead of evolving browser APIs, security standards, and extension ecosystem changes
• Participate in code reviews, testing, and continuous improvement of development processes

Requirements:

• You have extensive experience in software engineering: coding, testing, debugging, and automating complex TypeScript/JavasScript applications
• You're comfortable digging into third-party web applications you don't control — inspecting network traffic, DOM structure, and client-side code to understand how a page works
• You have the ability to learn new technologies quickly and are eager to do so — especially as browser extension platforms and manifest specs continue to evolve
• You focus on correctness, performance, and reliability of background processes
• You have excellent communication skills
• You are able to work self-sufficiently at times with minimal direction
• You can coordinate work effectively between yourself and developers working on non-browser platforms
• You have hands-on experience building or maintaining browser extensions (Chrome/Chromium Manifest V3 experience strongly preferred; Firefox/Edge a plus), including background scripts, content scripts, and extension messaging patterns
• You understand the security model of browser extensions - permissions, content security policy, isolated worlds, and safe communication between contexts
• You have experience building cybersecurity products or features, such as DLP (Data Loss Prevention), DSPM (Data Security Posture Management), or similar security/compliance tooling