Staff Software Engineer, Networking

Why Mozilla?

Mozilla Corporation is the non-profit-backed technology company that has shaped the internet for the better over the last 25 years. We make pioneering brands like Firefox, the privacy-minded web browser, and Pocket, a service for keeping up with the best content online. Now, with more than 225 million people around the world using our products each month, we’re shaping the next 25 years of technology and helping to reclaim an internet built for people, not companies. Our work focuses on diverse areas including AI, social media, security and more. And we’re doing this while never losing our focus on our core mission – to make the internet better for people.

The Mozilla Corporation is wholly owned by the non-profit 501(c) Mozilla Foundation. This means we aren’t beholden to any shareholders — only to our mission. Along with thousands of volunteer contributors and collaborators all over the world, Mozillians design, build and distribute open-source software that enables people to enjoy the internet on their terms.

What is a Staff Software Engineer at Mozilla?

A Staff Software Engineer is the next level from a Senior Software Engineer. At Mozilla this role can vary, but typically a Staff Engineer leads projects that require you to influence or direct the work of several engineers. Providing technical leadership, building team relationships, and helping the teams deliver on their objectives. The Staff Engineer is an expert in their domain. They provide feedback on our strategy and team goals, turning strategy into coordinated action for the team. They mentor others by stewarding responsibilities to junior and senior engineers so they can take on new ones, while collaborating with management on building team consensus and providing technical direction.

About this team and role:

The Mozilla Corporation’s networking team is looking for a skilled developer to work on a first-class networking stack and improve web experiences for many millions of Firefox users on desktop and mobile. The team is working on the core of the browser that moves the web. The fundamental network protocols and features like HTTP, QUIC, caching and DNS are our responsibility. We strive to provide a performant and secure browsing experience for our users. Furthermore, we work on advanced web platform networking API’s like Fetch, WebSockets and WebTransport. We improve our existing implementations and together with the broader community we advance the web through making contributions to the evolution of relevant standards.

Is improving networking protocols or multi-threaded applications  an exciting challenge for you? If you’re also enthusiastic about working collaboratively with a worldwide community, we’d love to hear from you!

Opportunities to collaborate with other browser teams, and working in the open is the norm. Firefox is a mature open source project always looking for new improvements. Much of Firefox is written in C++, but most recent components are written in Rust, including our QUIC stack. You’ll be responsible for defining projects, writing open source code, tests, specifications, building prototypes, solving problems, and analyzing data. You are encouraged to present your work in the web community, collaborate with academia, or contribute to relevant Internet standards. You’ll get feedback from real users and synthesize it into bug reports, feature designs, and strategic direction to make the web platform even better over time.

What you’ll do:

• Improve Firefox’s web browsing experience with a particular focus on the networking stack, network related protocols and API’s, e.g. QUIC, Fetch, WebSockets, WebTransport, etc.
• Design and implement new web platform features, or improvements to existing ones, in collaboration with the web community.
• Diagnose and fix problems in our multi-threaded codebase.
• Diagnose and fix platform-specific networking issues.
• Improve Firefox’s stability, correctness and performance.
• Analyze and reduce Firefox’s memory usage.
• Work cooperatively with other Mozillians to identify and correct issues.

What you’ll bring:

• 8+ years of experience as a Software Engineer.
• Skilled in C++ and Rust. Proficient in other languages.
• Skilled professional in HTTP protocols and implementations (HTTP/2, HTTP/3, QUIC, TLS, etc.)
• Experience implementing networking standards in production code.
• Familiarity with congestion control principles and modern OS dataplane primitives.
• Experience performing high level system design, project planning, roadmap strategy and  resourcing.
• Experience and comfortable working with distributed teams.
• Excellent communication skills, positive, team oriented,
• Experience with conflict resolution and decision making.
• Actively coaches and shares knowledge.
• Experience working on a cross-platform native application.
• Creative problem-solver and skilled debugger.
• Experience writing and debugging multi-threaded code.
• Experience with understanding and contributing to a large and complex multi-language code base.

We value a variety of backgrounds. You don’t need to check every box on this list to apply.

What you’ll get:

• Generous performance-based bonus plans to all eligible employees – we share in our success as one team
• Rich medical, dental, and vision coverage
• Generous retirement contributions with 100% immediate vesting (regardless of whether you contribute)
• Quarterly all-company wellness days where everyone takes a pause together
• Country specific holidays plus a day off for your birthday
• One-time home office stipend
• Annual professional development budget
• Quarterly well-being stipend
• Considerable paid parental leave
• Employee referral bonus program
• Other benefits (life/AD&D, disability, EAP, etc. – varies by country)

About Mozilla 

Mozilla exists to build the Internet as a public resource accessible to all because we believe that open and free is better than closed and controlled. When you work at Mozilla, you give yourself a chance to make a difference in the lives of Web users everywhere. And you give us a chance to make a difference in your life every single day. Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online.

Commitment to diversity, equity, inclusion, and belonging

Mozilla understands that valuing diverse creative practices and forms of knowledge are crucial to and enrich the company’s core mission.  We encourage applications from everyone, including members of all equity-seeking communities, such as (but certainly not limited to) women, racialized and Indigenous persons, persons with disabilities, persons of all sexual orientations, gender identities, and expressions.

We will ensure that qualified individuals with disabilities are provided reasonable accommodations to participate in the job application or interview process, to perform essential job functions, and to receive other benefits and privileges of employment, as appropriate. Please contact us at hiringaccommodation@mozilla.com to request accommodation.

We are an equal opportunity employer. We do not discriminate on the basis of race (including hairstyle and texture), religion (including religious grooming and dress practices), gender, gender identity, gender expression, color, national origin, pregnancy, ancestry, domestic partner status, disability, sexual orientation, age, genetic predisposition, medical condition, marital status, citizenship status, military or veteran status, or any other basis covered by applicable laws.  Mozilla will not tolerate discrimination or harassment based on any of these characteristics or any other unlawful behavior, conduct, or purpose.