Senior Security Engineer, Add-ons Operations

Requirements

• Experience building modern web applications.
• Strong experience with Python/Django or similar backend frameworks.
• Understanding of web security principles and practices.
• Strong collaboration and communication skills in a distributed team environment.
• Adept at navigating ambiguity, exploring solutions, and shaping direction in new problem spaces.
• Commitment to our values:
  • Welcoming differences
  • Being relationship-minded
  • Practicing responsible participation
  • Having grit

Nice to Haves

• Experience in building automated security systems.
• Exposure to cloud infrastructure (Google Cloud or similar).
• Contributions to open source projects.
• Experience with policy-compliant ecosystem moderation tools.

What You'll Be Doing

• Deliver major features and architectural improvements across the Add-ons stack, including automated moderation pipelines, Reviewer tools, and DevHub.
• Create robust observability systems and data-backed insights.
• Provide peer feedback, share knowledge, and help others grow.
• Improve platform reliability through deployments, monitoring, and incident response.
• Help keep the platform safe and trustworthy, with attention to security and user trust.
• Step in to resolve issues impacting users and developers, from small bugs to larger incidents.
• Collaborate with designers, product managers, QA, and community contributors to deliver end-to-end improvements.
• Contribute in the open through pull requests, code reviews, and discussions.
• Work on:
  • Full stack development: React/TypeScript frontends, Django backend, MySQL datastore.
  • Platform reliability: deployments, monitoring, and incident response on Google Cloud.
  • Feature development: submission flows, trust and safety signals, DevHub, and Reviewer tools modernization.
  • Ecosystem moderation: abuse report management, policy compliance, and ecosystem safety.
  • Open collaboration: We work in the open, with contributions from Mozilla staff and community members.

Perks and 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)