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Our unique corporate structure guarantees that every decision we make upholds our mission: to make sure the internet stays available, safe, and welcoming to everyone. Beholden to neither shareholders nor investors, Mozilla Corporation is wholly owned by the not-for-profit Mozilla Foundation

Along with 20,000+ volunteer contributors and collaborators all over the world, Mozilla Corporation’s staff designs, builds, and distributes software that allows people to enjoy the internet on their own terms. Our flagship product — the Firefox browser — has expanded into a family of products that protects users and alerts them of risks.

The Opportunity

The Firefox team is a community of engineers who care deeply about delivering the fastest, friendliest, most usable browser possible. We are responsible for making the things you see in the browser work securely, quickly, and well! We are looking for a Principal Engineer to help us develop and grow new machine learning driven products and tools. You will play a key role in enabling safe and healthy machine learning and AI driven experiences in Firefox. 

What is a Principal Software Engineer at Mozilla?

The responsibilities of a Principal Software Engineer at Mozilla can vary, but they typically 

• lead our most difficult technical projects that require directing multiple teams of experts (including experts in other functions)
• provide technical leadership
• build cross-team relationships
• help the teams deliver on their objectives.

Principal Engineers are industry experts in their domain. They help define our product strategy and goals affecting multiple teams and turn our strategy into coordinated action for those teams. They mentor others through  transfer of responsibilities to more junior engineers so they can take on new ones, while collaborating with management on building team consensus and providing direction. 

What you’ll do...

• Tackle large open-ended problems and drive them to completion, collaborating with other designers and engineers to make the web a better place.
• Identify strategic opportunities where machine learning models improve the experience in Firefox.
• Lead the design, development, and integration of innovative machine learning models in Firefox, collaborating cross functionally with product management, full stack engineering and design.
• Stay up-to-date with the latest advancements in machine learning, natural language processing, and related fields to ensure our methodologies remain innovative and relevant.
• Lead by example to upskill the team on AI and generate thought leadership.

What You Bring

• 10+ years experience as a Software Engineer.
• Deep knowledge of core web technologies and modern machine learning concepts like  deep learning, reinforcement learning, natural language processing, and generative AI, with expertise in one or more areas.
• Identify difficult problems that are important for the organization, collaborate across teams and the organization to find the best strategy to resolve.
• Ability to quickly analyze and solve sophisticated software development problems spanning multiple components, sometimes outside your area of expertise.
• Proven track record of technical leadership across multiple teams, showing a high degree of collaboration, flexibility, and respect for diverse perspectives
• Strong problem-solving skills and ability to communicate complex concepts to technical and non-technical stakeholders.
• You’re pragmatic about how to move things forward in specific timeframes including trade-offs and safeguards when implementing new functionality.
• Excellent written and verbal English communication skills and have participated effectively on a distributed team.
• Passion for responsible AI, transparent algorithms, and putting users’ needs first.

Bonus Points

• Knowledge of and experience with analyzing large-scale dataset utilizing statistical and machine learning tools
• Experience with design of experiments, survey design, and large-scale AB testing
• You have previously successfully contributed to an open source project.
• Track record of not only building one, but multiple projects deployed with an active user base.

We value a variety of voices within our team and at Mozilla. You don’t need to check every box on this list to apply.

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 [email protected] 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.

Group: B

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Req ID: R2264