Senior Security Engineer, Add-ons Operations

Stellenbeschreibung:

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. 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, all while never losing sight of our core mission – to make the internet better for people.

About this team and role

addons.mozilla.org (AMO) is the foundation of the Firefox add‑ons ecosystem – a showcase for developers to publish and grow their extensions and a place of discovery for millions of users. Behind the scenes, the DevHub enables developers to manage their extensions. The ecosystem is supported by reviewer tools and automated moderation systems.

What you’ll do

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.
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 front‑ends, 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.

What you’ll bring

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

Bonus points for

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 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 programme.
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 the chance to make a difference in the lives of Web users everywhere. And you give us the 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 encourages applications from everyone, including members of all equity‑seeking communities such as (but not limited to) women, racialised 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. Please contact us at 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, colour, 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 behaviour, conduct or purpose.