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# Software Engineer, Firefox Security

- **Company:** Mozilla Corporation
- **Location:** Málaga, Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** HTML, JavaScript (Programming Language), C++ (Programming Language), Cascading Style Sheets (CSS), Mobile Application Development, Software Debugging, Memory Management, Firefox, System Programming, Web Platforms, Multithreading, Web Technologies
- **Published:** November 6, 2026
- **Apply:** https://www.adzuna.es/details/5953559856

## About the Role

Contribute to our security initiatives: Work across teams to investigate security issues, identify root causes, and deliver robust, maintainable fixes.
Improve browser reliability and performance: Diagnose and resolve issues affecting stability, correctness, performance, and memory usage in a complex, multithreaded environment. What you'll bring: Systems programming experience and security knowledge: 3+ years of experience in low-level software engineering, strong proficiency in C and/or C++, and a solid understanding of security fundamentals.
Debugging and problem-solving skills: Experience diagnosing and resolving issues in multithreaded, cross-platform native applications, including memory and performance challenges.
Web platform and modern systems experience: Familiarity with web technologies (HTML, CSS, JavaScript) and interest or experience in Rust; ability to work effectively within large, complex, multi-language codebases.
Effective collaboration and communication: Experience working with distributed teams and communicating technical ideas clearly in writing and conversation.