Senior Software Engineer, Firefox Security

Mozilla; Germany (OH); Hybrid; USD 77,776 - 104,083; Full time

Benefits offered by this job

Performance-based bonus plans

Medical, dental, and vision coverage

100% immediate retirement vesting

Quarterly wellness days

Country specific holidays

Home office stipend

Professional development budget

Well-being stipend

Paid parental leave

Employee referral bonus program

Job summary

Mozilla is hiring for a role focused on advancing Firefox's security architecture and developing web platform features. The successful candidate will work within a dynamic team to improve browser performance and contribute to security initiatives. Essential qualifications include proficiency in C/C++ and a solid understanding of security principles.

Benefits include performance-based bonuses, comprehensive health coverage, and generous retirement contributions, plus opportunities for professional development and inclusivity for all applicants.

Qualifications

• Experience in software engineering with proficiency in C/C++.
• Ability to design, implement, test, and maintain complex software systems.
• Expertise in diagnosing issues in multi-threaded applications.

Responsibilities

• Advance Firefox's security architecture and cryptography stack.
• Design and implement web platform security features.
• Investigate and resolve issues impacting browser reliability and performance.
• Collaborate on security initiatives and identify issues.
• Contribute to technical design and project planning.

Skills

C/C++ proficiency

Security principles understanding

Debugging skills

Collaborative communication

Growth mindset

Web technologies familiarity

Job description

Responsibilities

• Advance Firefox's security architecture and cryptography stack: Contribute to improvements in Firefox's core security systems, with a focus on cryptographic protocols, WebPKI, and security-sensitive web APIs. Help implement and maintain security features that support the evolution of public key infrastructure on the web.
• Design and implement web platform security features: Develop and ship web platform features in collaboration with teammates and the broader web community. Contribute to standards-based, secure, and interoperable implementations across Firefox.
• Improve browser reliability, performance, and resource efficiency: Investigate and resolve issues impacting stability, correctness, and performance. Analyze and improve memory usage and efficiency within a complex, multi-threaded browser environment.
• Collaborate on security initiatives: Partner with engineers across teams to identify, prioritize, and address security issues. Participate in debugging, root cause analysis, and implementation of effective long-term solutions.
• Contribute to technical design and planning: Participate in technical discussions, design reviews, and project planning for security-related initiatives. Help evaluate tradeoffs and contribute to engineering decisions within your area of work.

Qualifications

• Strong software engineering and security fundamentals: Experience in software engineering, with proficiency in C/C++ and a solid understanding of security principles, including cryptographic protocols and implementations.
• Experience building and maintaining complex software systems: Ability to contribute to the design, implementation, testing, and maintenance of software in large-scale or security-sensitive environments.
• Strong debugging and problem-solving skills: Expertise in diagnosing and resolving issues in multi-threaded, cross-platform native applications, including performance and memory-related challenges.
• Collaborative and effective communicator: Ability to work effectively with distributed teams, communicate technical concepts clearly, and collaborate constructively to solve problems.
• Growth mindset and willingness to learn: Demonstrated curiosity and desire to deepen expertise in browser security, cryptography, and systems programming while continuously improving engineering skills.
• Web platform and modern systems experience: Familiarity with web technologies and interest or experience in Rust. Comfortable working within large, complex, multi-language codebases.

Benefits

• Generous performance-based bonus plans to all eligible employees.
• Rich medical, dental, and vision coverage.
• Generous retirement contributions with 100% immediate vesting regardless of whether you contribute.
• Quarterly all-company wellness days.
• 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).

EEO Statement

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.

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 women, racialized and Indigenous persons, persons with disabilities, persons of all sexual orientations, gender identities, and expressions. We will provide reasonable accommodations to qualified individuals with disabilities. Please contact [e-mail] to request accommodation.

Hiring Ranges

Remote Germany – €68,000—€91,000 EUR