Principal Software Engineer, Browser Automation for AI Agents

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Why Mozilla?

Mozilla Corporation is a non-profit-backed technology company dedicated to shaping the internet for the better. For over 25 years, we've pioneered brands like Firefox, the privacy-minded web browser. With over 225 million monthly active users, we are actively shaping the next 25 years of technology, focusing on reclaiming an internet built for people, not companies. Our work spans diverse areas including AI, social media, and security, all while staying true to our core mission of making the internet better for people.

Mozilla Corporation is wholly owned by the non-profit 501(c) Mozilla Foundation. This unique structure means we are not beholden to shareholders, but rather to our mission. In collaboration with thousands of volunteer contributors worldwide, Mozillians design, build, and distribute open-source software that empowers individuals to experience the internet on their own terms.

About This Team and Role

The New Products team at Mozilla is building a browser-automation stack specifically designed for AI agents. Our mission is to provide developers with an effortless way to integrate fast, reliable web interactions into their agentic applications.

We are seeking a founding Principal Software Engineer to establish the technical vision, architect the platform, and contribute significantly through hands-on production code development. You will lead a small, agile engineering group, delivering the core libraries, services, and tooling that will power the next generation of intelligent web automation. If you are passionate about hands-on development, enjoy shipping code that developers value, and are excited about shaping green-field products from inception, we encourage you to apply.

What You'll Do:

• Technical Strategy & Architecture: Define and articulate the long-term technical roadmap for our browser-automation stack, ensuring a balance between rapid iteration, maintainability, and scalability.
• Hands-On Development: Write elegant, high-performance code daily using languages such as Go, Ruby on Rails, and TypeScript. Rapidly prototype, benchmark, and deploy features to production.
• System Design & Infrastructure: Design distributed, fault-tolerant services and developer-facing SDKs/APIs. Take ownership of cloud infrastructure, CI/CD pipelines, security, and observability.
• Team Leadership & Mentorship: Foster the growth, development, and inspiration of a world-class engineering team. Conduct thorough code reviews, establish a strong engineering culture, and cultivate an environment of technical excellence and psychological safety.
• Collaboration & Product Direction: Work closely with product, design, and developer-relations teams to ensure technical decisions align with developer needs and business objectives. Translate community feedback into actionable product improvements.
• Stakeholder Communication: Clearly communicate complex technical trade-offs to executives, partners, and cross-functional teams. Provide regular updates on progress, identify risks, and propose mitigation strategies.

What You'll Bring:

• Experience: 10+ years of software engineering experience, with a focus on building high-performance developer tools, SDKs, or distributed systems. At least 3 years of experience leading technical teams or significant projects.
• Technical Proficiency: Expert-level proficiency in at least two of the following languages: Go, Ruby (Rails), Python, or TypeScript/JavaScript.
• System Architecture: Proven track record of architecting and shipping complex, high-throughput systems in production environments (cloud, edge, or hybrid).
• Web Automation Expertise: Deep understanding of browser internals, automation frameworks (e.g., Playwright, Puppeteer, Selenium), and secure web interaction paradigms.
• AI/ML Familiarity: Hands-on experience with or strong opinions on modern AI/ML workflows or agent frameworks such as LangChain, LlamaIndex, or custom in-house systems.
• Code Quality: Strong commitment to code quality and testability.