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# software engineer

- **Company:** Mozilla Corporation
- **Location:** Murcia, Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), Data Analysis, C++ (Programming Language), Cloud Engineering, Computer Programming, Databases, Continuous Integration, Programming Tools, Firefox, Python (Programming Language), Open Source Technology, Reliability Engineering, Software Engineering, TypeScript, Cloud Platform System
- **Published:** October 27, 2026
- **Apply:** https://www.adzuna.es/details/5942880729

## About the Role

Staff Site Reliability Engineer, Tools & SystemsTeam: FirefoxLocations: Remote Germany, Remote Canada, Remote Belgium, Remote Spain, Remote Netherlands, Remote Sweden, Remote France, Remote UK, Remote FinlandWe are looking for an experienced and versatile software engineer to work on the tools and systems that support Firefox engineering.Why Mozilla?, Experience with C++ or Rust is useful.Experience building and deploying and operating production systems in cloud environments, including utilizing infrastructure as code such as Terraform.Experience across several areas such as CI/CD, containers and orchestration, networking, databases, observability, or developer tooling.Experience using data, telemetry, and metrics to investigate technical problems and make decisions.Familiarity with modern AI?assisted development tools and an understanding of their capabilities, limitations, and appropriate use.How you work:You are comfortable jumping into unfamiliar systems and getting them into a sustainable state.You enjoy moving across projects and technical domains, taking ownership of problems and looking for patterns that make the next one easier to solve.You work effectively across disciplines and can translate between software, infrastructure, and operational concerns.You combine hands?on engineering with systems thinking and

## Description

We are looking for an engineer with strong software development skills and meaningful experience deploying and operating production systems.Our Cloud Engineering teams provide shared platforms and foundational services, while engineering teams own the applications and services they run on them.
A key part of this role is helping teams succeed in that model by solving difficult operational problems, establishing standards and patterns, and building tooling and automation that makes systems easier to operate.
You will also contribute directly to the software, tools, and systems that support Firefox engineering.You will work across projects and technical domains, joining teams or existing efforts when needed and independently taking on problems that require focused ownership.We build in the open.
Open source is fundamental to how we work, and contributing back to the broader open-source ecosystem is an important part of the role.What You'll DoDesign, build, deploy, and operate software and systems supporting Firefox engineering.Contribute to developer tooling, CI/CD, workflow automation, and AI-assisted development tools.Own complex technical problems end-to-end across software, cloud, and operational layers, improving reliability, performance, observability, and cost efficiency.Work with Firefox engineering, Cloud Engineering, IT, and other teams to solve problems that span technical and organizational boundaries.Use telemetry, metrics, and data analysis to investigate problems and guide engineering decisions.Contribute to architecture and technical strategy, identifying recurring problems and solutions that can be applied across teams.What you'll bring:Strong programming skills in languages such as Python or JavaScript/TypeScript.