Senior Software Engineer

Mozilla is a non-profit-backed technology company focused on building an open, accessible, and privacy-minded internet through products such as Firefox. The Senior Software Engineer will build and own backend services, integrations, APIs, and cloud infrastructure for the Ecosystem Services Team while operating services reliably in production. The role also involves incident support, observability, collaboration across teams, security and privacy reviews, and mentoring engineers.

Responsibilities:

• 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 rather than handing them off
• Work closely with our CloudEng Team to maintain and improve production environments, including monitoring and alerting with tools such as OpenTelemetry, Sentry, Prometheus, and Grafana
• Participate in an on-call / off-hours support rotation, triaging and resolving production issues, partnering with CloudEng and support teams to investigate incidents, address bug reports, and keep the application running reliably
• Periodically rotate into a support role, handling releases, dependency updates, and incoming work requests from customer support and other stakeholders
• Thoughtfully apply AI-assisted development tools to move faster and raise quality, while maintaining good judgment about where they fit and where they don't
• Partner with and support stakeholders (e.g. front-end, platform), ensuring backend systems, APIs, and data contracts meet their needs
• 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

Requirements:

• • 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 back-end engineering projects
• • Proficiency with PostgreSQL and SQL query optimization, including relational schema design and migrations with a query builder such as Knex
• • Hands-on DevOps experience on Google Cloud Platform (GCP), with Docker-based build and deploy pipelines. You are comfortable deploying, operating, and troubleshooting services in the cloud rather than handing that responsibility to someone else
• • Hands-on experience with observability and monitoring tooling such as Sentry and Grafana
• • A pragmatic commitment to shipping quality work. You care about the quality and reliability of what you ship, you make sensible trade-offs under real constraints, and you consistently move work to and into production
• • Strong engineering judgment. You can navigate ambiguity, weigh trade-offs, and make sound decisions with incomplete information, and you know when to ask for input
• • A genuine ownership mindset. You are excited to own a service end to end and have a track record of operating what you build in production, including experience with on-call or off-hours production support
• • Experience mentoring junior engineers and driving technical excellence in code quality, testing, and process improvements
• • Performance / load testing
• • Experience with IaC tools such as Terraform and Kubernetes
• • Open-source contributions or personal engineering projects
• • Djangoexperience