Staff Firefox Performance Engineer

The Mozilla Firefox Performance team is a community of engineers who care deeply about delivering the fastest browser possible. We are the team responsible for making all parts of the browser go fast.

Our team is geographically-distributed, and working in the open is the norm. We contribute to the code driving the Firefox browser on a number of platforms - Windows, Android, Linux, and macOS. Our focus is on finding and fixing things that slow down the browser as well as helping other teams write fast and reliable code to make Firefox excellent for users.

Do you value curiosity and enjoy finding a needle in a haystack? Do you approach problems by looking at the system as a whole? Do you want to help lead and shape the future of the Internet? Do you like making things blazingly fast? If so, we’d love to hear from you.

What you'll do:

Write code and tests, build prototypes, tackle problems, profile and analyze performance bottlenecks

Learn about a wide variety of problems and solutions across a large, complex, and evolving codebase

Use several programming languages (e.g., C++, JavaScript, Kotlin, Rust, Python) and techniques to fix performance issues, with an emphasis on C++ and JavaScript

Help to educate engineers on other teams about writing more performant code through code reviews, giving talks, implementing tooling, and/or writing documentation

Break down complex performance problems into actionable next steps and drive them to completion

Partner with engineering teams across the organization to support performance efforts, and lead them within your area

Contribute to the direction of performance benchmarks and help prioritize the improvements that matter most

Own the performance of a significant area of the browser end to end, and contribute to the Performance team's technical roadmap

Work with driven, committed team members to help bring the Open Web to millions of people

What you'll bring:

BS/MS in CS or CE, and 5+ years of relevant experience

Deep proficiency in C++

Working proficiency in JavaScript

You have proven experience developing performance-critical software

You take an experimental and measured approach to solving problems (measurement, and using experiments to diagnose an issue or prove out a solution)

Proven skill in debugging and analyzing performance bottlenecks, and using profiling tools to diagnose and fix issues (VTune, Xperf, other sampling based profilers)

Experience with at least one of: multithreading and concurrency, disk I/O, or GPU work

Track record of driving projects to completion, including work spanning more than one engineer.

Experience collaborating with engineers on other teams to deliver shared goals.

An interest and ability to work in a distributed team (which requires good asynchronous written communication skills as well as good verbal communication skills)

Bonus points if you have any of the following:

Familiarity with Web Standards or patterns

Familiarity with Android or Windows OS application programming

A solid understanding of statistics

Prior experience working on a modern web browser

We value a variety of voices on the Performance Team and at Mozilla. 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)

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: C

#LI-REMOTE

Req ID: R3245

Hiring Ranges:

US Tier 1 Locations$163,000—$218,000 USDUS Tier 2 Locations$150,000—$200,000 USDUS Tier 3 Locations$139,000—$185,000 USD