Senior Software Engineer, Firefox Security

Imagine a world where the internet truly serves people first, where your digital safety isn't just an afterthought, but the very foundation of every online experience. That's the vision Mozilla champions, and it's where you come in. We're on the hunt for a brilliant Senior Software Engineer specializing in Firefox Security, someone ready to deeply impact how millions around the globe browse the web securely. This isn't just another coding job; it's an opportunity to fortify the internet's future, working with a team passionate about privacy and user protection, all from anywhere in the world.

Overview

Mozilla has spent over two decades shaping the internet, driven by our mission to keep it open, accessible, and user-centric. As the proud creators of Firefox, a browser used by more than 225 million people monthly, we stand at the forefront of digital innovation, focusing on areas like AI, social media, and crucially, security. We're unique because we're wholly owned by the non-profit Mozilla Foundation, meaning our loyalty is to our mission, not shareholders. Join us as a Senior Software Engineer, Firefox Security. This is a fully remote, global role, inviting top talent from anywhere on Earth to contribute to a cause that truly matters.

Key Responsibilities

Design, implement, test, and ship cutting-edge security features that strengthen Firefox’s security posture for both enterprise and individual users.
Lead the design and architectural planning of new security and hardening features from concept to production deployment.
Proactively identify potential security vulnerabilities within Firefox and its ecosystem, then collaborate with teams to develop and integrate effective mitigations.
Contribute to the continuous improvement of Firefox's security by staying informed about emerging threats, web security standards, and best practices.
Engage actively with the open-source community, contributing to and reviewing code, and fostering a culture of security awareness.
Mentor junior engineers, share knowledge, and contribute to the team's overall technical growth and adherence to secure coding practices.

Requirements

At least 5+ years of professional experience in software engineering, with a significant focus on security.
Deep expertise in C++ and/or Rust, demonstrated through substantial project contributions.
Solid understanding of web browser architecture, operating system security principles, and common web vulnerabilities (e.g., OWASP Top 10).
Experience designing and implementing security features, including sandboxing, exploit mitigations, and secure coding practices.
Familiarity with the open-source development model and a willingness to contribute effectively in a distributed team environment.
Exceptional problem-solving skills and a proactive approach to identifying and addressing complex security challenges.
Excellent communication skills, capable of explaining intricate technical concepts to diverse audiences, both technical and non-technical.
Ability to work independently, manage multiple priorities, and thrive in a fully remote, asynchronous global team setting.

What You'll Gain

Meaningful Impact: Directly contribute to a product used by millions, making a tangible difference in their online safety and privacy.
Mission-Driven Culture: Be part of an organization dedicated to making the internet a healthier, more equitable space for everyone, free from shareholder pressures.
Innovative Challenges: Tackle complex and cutting-edge security problems in a constantly evolving threat landscape, pushing the boundaries of what's possible in browser security.
Global Collaboration: Work alongside a diverse, passionate, and highly skilled team of engineers and security experts from around the world.
Professional Growth: Opportunities for continuous learning, skill development, and influence within the open-source community.