Senior Software Engineer, Add-Ons

💼 Full-time🗓 2026-09-22 → 2026-09-26

Core

Build resilient systems and modernize the architecture for the Firefox add-ons ecosystem, including automated moderation pipelines, developer tools, and platform reliability.

Role type

Senior Software Engineer (Full Stack)

Builds

Automated moderation pipelines, Reviewer tools, DevHub, and submission flows for the Firefox add-ons platform.

Domain

Internet infrastructure / Web platform operations

Deliverable

Required skills

Full stack development, Python/Django, React/TypeScript, MySQL, web security principles, cloud infrastructure management, incident response, observability system design

Preferred skills

Automated security systems, Google Cloud, open source contributions, policy-compliant ecosystem moderation tools

Technologies

React, TypeScript, Django, MySQL, Google Cloud

Responsibilities

Deliver major features and architectural improvements across the Add-ons stack, create robust observability systems, improve platform reliability through deployments and monitoring, resolve user and developer issues, collaborate on end-to-end improvements, contribute to open source via pull requests and code reviews

Seniority

Senior, hands-on IC

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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.