Job Description

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.

About this team and role:

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 Staff Machine Learning Engineer to help us develop and grow new Generative AI driven products and tools. You will play a key role in enabling safe and healthy machine learning and Generative AI driven experiences in Firefox. 

What is a Staff Engineer at Mozilla? 

A Staff Engineer is the next level from a Senior Engineer. At Mozilla this role can vary but typically a Staff Engineer is a domain expert who leads others within a single team to tackle multi-month projects. Tasks that may be initially ambiguous or require significant planning and require them to influence or direct the work of several engineers. They sequence deliverables and manage risks in their team's projects, provide feedback on our strategy and goals affecting the team, and turn our strategy into action for their team members. Staff Engineers mentor others by stewarding some responsibilities to more junior and senior engineers so they can take on new ones. They collaborate with management on building team consensus and providing direction. Staff Engineers identify gaps and opportunities for improvement to enable a culture of inclusion and allyship, at all levels of the organization.

What you’ll do:

• Lead the design, development, and integration of Generative AI solutions in Firefox, collaborating cross functionally with product management, full stack engineering and design.


• Build infrastructure for training and inference of LLMs and small language and vision models for use cases on the web and mobile Firefox product experiences.


• Implement robust validation and testing procedures to ensure the developed models' generalizability and reliability


• Continuously monitor and optimize deployed models for performance and efficiency

What you'll bring:

• 6+ years experience as a Machine Learning engineer building tooling and services for machine learning applications in production.


• Experience with designing and building machine learning tooling and infrastructure for training, deploying, inference and validation of models.


• Experience with distributed systems and platforms for AI integrations across a breadth of applications such as LLM APIs, Cloud based and open source tooling.


• Leading architecture designs to execution independently and track record of improving the team’s overall AI development velocity.


• Strong problem-solving skills and ability to communicate complex concepts to technical and non-technical stakeholders.


• Experience working collaboratively with product managers, project managers, and/or other non-engineering teams.


• Effective documentation and communication skills on a distributed team.


• Commitment to our values:




• Welcoming differences


• Being relationship-minded


• Practicing responsible participation


• Having grit

Bonus Points

• Knowledge of and experience with using LLM solutions across different cloud providers


• 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.


• Experience with responsible AI, transparent algorithms, and putting users’ needs first.


• Excellent communication skills, both in written and presentation form. You have the ability to quickly distill sophisticated topics into concepts that are tailored for your target audience.


• You are a lifelong learner, and continue to refine and improve your skills when you see an opportunity to do so.


• Experience with the browser extensions architecture or ecosystem.


• Experience working in open source environments.

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 orientation s, 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.

Group: C

#LI-REMOTE

Req ID: R2593

Hiring Ranges:

Remote Spain

€105.000—€153.000 EUR

Job Tags

Full time, Immediate start, Remote work, Home office,

Similar Jobs