Senior Backend Engineer, Ecosystems - Mozilla

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. Now, 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.

The Mozilla Corporation is wholly owned by the non-profit 501(c) Mozilla Foundation. This means we aren’t beholden to any shareholders — only to our mission. Along with thousands of volunteer contributors and collaborators all over the world, Mozillians design, build and distribute open-source software that enables people to enjoy the internet on their terms.

About this Team and Role

As a Senior Software Engineer on the Ecosystem Services Team, you’ll build and own back-end systems and the integrations that keep our services running, help maintain and evolve the cloud infrastructure the application runs on, and play an active role in keeping the service reliable and healthy in production. You'll collaborate closely with frontend engineers, product managers, CloudEng, and UX and design partners to deliver reliable features.

Ecosystem Services builds and operates the back-end platforms that power Mozilla products and services, with a focus on privacy, security, and delivering critical functionality to Firefox and millions of users worldwide. Our portfolio includes Privacy Services (Mozilla VPN, Relay, Monitor), AutoPush (Web Push platform), and Remote Settings.

What You’ll Do

• Lead backend development, building and maintaining server-side logic
• Take real ownership of the services you work on: deploy them, operate them, and keep them healthy in production
• Work closely with our CloudEng Team to maintain and improve production environments, including monitoring and alerting with OpenTelemetry, Sentry, Prometheus, and Grafana
• Participate in an on-call / off-hours support rotation, triaging and resolving production issues
• Periodically rotate into a support role, handling releases, dependency updates, and incoming work requests
• Thoughtfully apply AI-assisted development tools to move faster and raise quality
• Partner with frontend and cross-functional teams to align on project goals, contribute to API design, and ensure backend systems, APIs, and data contracts meet their needs
• Participate in code reviews to maintain high standards of code quality and system reliability
• Participate in security and privacy reviews, ensuring all data protection measures meet compliance standards

What You’ll Bring

• 4+ years of experience in software development with a strong focus on backend technologies
• Strong professional experience with Python, TypeScript/Node.js, or Rust building back-end services and confidence leading projects
• Proficiency with PostgreSQL and SQL query optimization, relational schema design, and migrations with query builders like Knex
• Hands-on DevOps experience on Google Cloud Platform (GCP), with Docker-based build and deploy pipelines
• Hands-on experience with observability and monitoring tooling such as Sentry and Grafana
• A pragmatic commitment to shipping quality work under real constraints
• Strong engineering judgment to navigate ambiguity and make sound decisions
• Genuine ownership mindset with a track record of operating what you build in production, including on-call experience
• Experience mentoring junior engineers and driving technical excellence

Bonus Points For

• Performance / load testing
• Experience with IaC tools such as Terraform and Kubernetes
• Open-source contributions or personal engineering projects
• Django experience