Senior Software Engineer, Add-Ons

Job description

About this role

Mozilla (maker of Firefox) is hiring a Senior Software Engineer for the Add-ons team. addons.mozilla.org (AMO) is the foundation of the Firefox add-ons ecosystem. It’s a showcase for developers to publish and grow their extensions, and a place of discovery for millions of users who customize Firefox to make it their own. Behind the scenes are the DevHub which enables developers to manage their extensions. To manage the ecosystem there are a series of Reviewer tools and automated moderation systems.

Responsibilities

• - Deliver major features and architectural improvements across the Add-ons stack, including automated moderation pipelines, Reviewer tools, and DevHub.
• - Help establish and maintain engineering standards across areas such as code review, definition of done, production readiness, runbooks, incident response, on-call practices, coding conventions, and infrastructure as code
• - Create robust observability systems and data-backed insights.
• - Provide peer feedback, share knowledge and help others grow.
• - Build and improve the systems that enable Add-ons engineering to safely develop, deploy, observe, and operate production services.
• - Improve our CI/CD pipelines using declarative, pipeline-as-code approaches that make changes reproducible, testable, and easy to review.
• - Deliver work iteratively using a visible backlog, short feedback cycles, retrospectives, and demonstrations to stakeholders.
• - Write clear technical documentation, including design notes, Architecture Decision Records, runbooks, and incident write-ups.

Qualifications and requirements

• - Strong hands-on experience building and maintaining production applications with Python/Django.
• - Experience operating and improving production software systems where reliability and safe delivery matter.
• - Strong experience with CI/CD systems and treating pipelines and infrastructure declaratively as code.
• - Experience designing or improving automated testing and deployment workflows, including integration testing and staged or progressive delivery.
• - Strong understanding of observability as an engineering discipline, including metrics, logging, tracing, service-level objectives, and actionable alerting.
• - Experience building or maintaining internal tools or platforms used by other engineering teams, with an understanding that internal systems have users, reliability expectations, roadmaps, and lifecycle considerations.
• - Experience defining or improving engineering practices such as code review standards, operational readiness, runbooks, incident response, on-call expectations, or definitions of done.
• - Ability to read and understand unfamiliar codebases and trace application behavior across frontend, backend, asynchronous jobs, data stores, and infrastructure.