Senior Software Engineer, Firefox Security

Mozilla
Netherlands
Remote

Who this role is best for

Best suited to systems engineers with security expertise working in open-source software and browser security.

Best fit for

  • Candidates with systems programming experience and a passion for browser security and privacy
    — “Design, build and implement security and hardening features for enterprise users”
  • Individuals familiar with multithreaded environments and cross-platform development
    — “Diagnose and resolve issues affecting stability, correctness, performance, and memory usage in a complex, multithreaded environment”

Things to consider

  • The role is likely to require a strong understanding of cryptographic protocols and WebPKI
    — “Improve Firefox’s core security mechanisms including cryptographic protocols, WebPKI”
  • Candidates must be prepared to work with distributed teams and maintain clear communication
    — “Experience working with distributed teams and communicating technical ideas clearly”

How to stand out

  • Highlight your experience in low-level systems programming and security-related projects
    — “3+ years of experience in low-level software engineering”
  • Demonstrate your ability to debug and resolve performance and memory issues in complex systems
    — “Diagnose and resolve issues affecting stability, correctness, performance, and memory usage”
  • Showcase your work with multi-language codebases and cross-platform development
    — “ability to work effectively within large, complex, multi-language codebases”
  • Emphasize your background in systems security and privilege isolation mechanisms
    — “Contribute to and drive cutting-edge improvements to Firefox’s core security posture”
  • Demonstrate your interest in or experience with Rust alongside traditional web technologies
    — “interest or experience in Rust; ability to work effectively within large, complex, multi-language codebases”
Pace · SteadyCollaboration · HighAutonomy · MediumDecision Impact · Team

Derived from job-description analysis by Serendipath's career intelligence engine.

What success looks like

  • design and implement security features
  • advance security architecture
  • contribute to security initiatives
  • improve browser reliability and performance
Typical background
systems programmingsecurity engineering

Skills & requirements

Required

Systems-programmingSecurity-knowledgeDebuggingWeb-platform-experienceCollaboration

Preferred

RustMultithreaded-environment

Stack & domain

CC++RustSecurityDebuggingProblem-solvingCollaborationCommunicationFirefoxWeb Technologies

About the role

Original posting from Mozilla via Greenhouse

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. 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. 

What you’ll do:

Design, build and implement security and hardening features for enterprise users: Design, implement, test, and ship cutting-edge security features that strengthen Firefox’s security posture.

Advance Firefox’s security architecture across multiple operating systems: Contribute to and drive cutting-edge improvements to Firefox’s core security posture, by building privilege isolation and moving trust boundaries or Strengthen Firefox’s security architecture: Improve Firefox’s core security mechanisms including cryptographic protocols, WebPKI, and security-sensitive web APIs.

Contribute to our security initiatives: Work across teams to investigate security issues, identify root causes, and deliver robust, maintainable fixes.

Improve browser reliability and performance: Diagnose and resolve issues affecting stability, correctness, performance, and memory usage in a complex, multithreaded environment.

What you’ll bring:

Systems programming experience and security knowledge: 3+ years of experience in low-level software engineering, strong proficiency in C and/or C++, and a solid understanding of security fundamentals.

Debugging and problem-solving skills: Experience diagnosing and resolving issues in multithreaded, cross-platform native applications, including memory and performance challenges.

Web platform and modern systems experience: Familiarity with web technologies (HTML, CSS, JavaScript) and interest or experience in Rust; ability to work effectively within large, complex, multi-language codebases.

Effective collaboration and communication: Experience working with distributed teams and communicating technical ideas clearly in writing and conversation.

What you’ll get:

Generous performance-based bonus plans to all eligible employees - we share in our success as one team

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 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 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: D

#LI-REMOTE

Req ID: R3247

Hiring Ranges:

Remote Netherlands€66.000—€88.000 EUR

Source: Mozilla careers (Greenhouse)

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