Overview

As a Senior Software Engineer on the AMO/DevHub domain, you will help shape the Firefox add-ons ecosystem by delivering major features and architectural improvements. You’ll partner with engineers, reviewers, product leads, and the community to modernize the platform, improve reliability, and scale review and moderation. You’ll build observable, data-driven systems and guide the team with strong engineering practices. This role offers impact at scale and a chance to contribute to an open, privacy-respecting internet.

Compensaciones / Ventajas

- generous performance-based bonus
- medical, dental, and vision coverage
- retirement contributions with immediate vesting
- well-being stipend and wellness days
- home office stipend
- professional development budget

Responsabilidades

- Deliver major features and architectural improvements across the Add-ons stack (automated moderation pipelines, Reviewer tools, DevHub)
- Establish and maintain engineering standards (code review, production readiness, incident response, runbooks, IaC)
- Create robust observability systems and data-backed insights
- Mentor peers and share knowledge to grow the team
- Improve CI/CD pipelines with declarative, pipeline-as-code approaches
- Deliver work iteratively with clear backlog and stakeholder reviews
- Produce technical documentation (design notes, ADRs, runbooks, incident reports)
- Trace and diagnose failures across frontend, backend, asynchronous jobs, data stores, and infra
- Collaborate with designers, PMs, QA,



and community contributors to ship end-to-end improvements
- Contribute to open source via PRs, code reviews, and discussions
- Work on: feature development (submission flows, trust signals, DevHub/Reviewer tools modernization)
- AMO stack: Python/Django, MySQL, React/TypeScript, asynchronous processing
- Internal developer platforms: build tools to help teams ship and operate safely

Requisitos principales

- Hands-on production-grade Python/Django experience
- Proven reliability-focused production software operations
- Strong CI/CD experience and declarative infrastructure
- Experience designing automated tests and progressive delivery
- Strong observability knowledge (metrics, logging, tracing, SLOs, alerting)
- Experience building internal tools/platforms used by engineers
- Defining/improving engineering practices (code review, runbooks, incident response)
- Ability to read unfamiliar codebases and trace end-to-end behavior
- Proven debugging of complex production issues and turning learnings into improvements
- Strong technical writing (design docs, ADRs, runbooks, incident reports)
- Experience working with a visible backlog and stakeholder feedback
- Strong collaboration and communication in distributed teams
- Willingness to mentor peers on reliability practices
- Commitment to Mozilla values: welcoming differences, relationship-minded, responsible participation, grit

- collaboration
- communication
- mentorship
- Python/Django
- MySQL
- React/TypeScript

📌 Senior Software Engineer, Add-Ons - Mozilla Corporation (España)
🏢 Mozilla
📍 España