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# Senior OS Integration Engineer - Open Source Firefox Remote

- **Company:** Mozilla
- **Location:** Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** Software Applications, C++ (Programming Language), Firefox, Open Source Technology, Software Engineering
- **Published:** November 13, 2026
- **Apply:** https://www.jobleads.com/es/job/senior-os-integration-engineer-open-source-firefox-remote--spain--e556a4329596bc616b71f774727f35039

## About the Role

You'll bring 5+ years of software engineering, strong C/C++ and desktop app experience, and a commitment to secure coding practices. You'll thrive in a distributed environment while delivering high-quality releases and engaging with

## Description

Mozilla is seeking a Senior Software Engineer for OS Integration to develop fixes, improvements and new features for Firefox. You'll contribute to cross-platform work and maintenance of the installer and updater, collaborating with engineers across distributed teams.

You'll bring 5+ years of software engineering, strong C/C++ and desktop app experience, and a commitment to secure coding practices. You'll thrive in a distributed environment while delivering high-quality releases and engaging with