Staff Performance Engineer, Firefox
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Job Description
Staff Firefox Performance Engineer optimizing performance-critical code in Mozilla’s open-source Firefox browser. Diagnosing bottlenecks and leading cross-team improvements for millions of users.
Responsibilities:
- Write code and tests, build prototypes, tackle problems, and profile and analyze performance bottlenecks
- Learn and solve problems across a large, complex, and evolving codebase
- Use C++, JavaScript, Kotlin, Rust, and Python to fix performance issues, with emphasis on C++ and JavaScript
- Educate engineers on other teams through code reviews, talks, tooling, and documentation
- Break down complex performance problems into actionable next steps and drive them to completion
- Partner with engineering teams across the organization to support and lead performance efforts
- Contribute to performance benchmark direction and prioritize important improvements
- Own browser performance for a significant area end to end and contribute to the Performance team's technical roadmap
- Work with team members to bring the Open Web to millions of people
Requirements:
- BS/MS in CS or CE, and 5+ years of relevant experience
- Deep proficiency in C++
- Working proficiency in JavaScript
- Proven experience developing performance-critical software
- Experimental and measured approach to solving problems using measurement and experiments
- Proven skill in debugging and analyzing performance bottlenecks, and using profiling tools such as VTune and Xperf
- 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
- Interest and ability to work in a distributed team, with strong asynchronous written and verbal communication skills
Benefits:
- 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)
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