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# Software Engineer, Privacy

- **Company:** Mozilla Corporation
- **Location:** Barcelona, Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), C++ (Programming Language), Firefox, Gecko (Software), Python (Programming Language), Raw Data, Systems Architecture, WebKit, Rust (Programming Language), Multithreading, Information Technology, Low Latency, Machine Learning Operations, Web Architecture
- **Published:** November 2, 2026
- **Apply:** https://www.adzuna.es/details/5949969759

## About the Role

We are looking for a Senior Software Engineer to support the Privacy Team to advance the Firefox Web Platform.What You'll DoImplement Privacy-improving, anti-tracking and threat intelligence protection into the Firefox web browser to mitigate user tracking and phishing.Implement architectural improvements into Gecko, the browser engine underlying Firefox.Build performant, low-latency, and maintainable C++, JavaScript and Rust codeWork as part of a geographically distributed team in an asynchronous manner (mostly Europe and US-East).
What you'll bring:Bachelor's degree in computer science, engineering, or a related program; or equivalent work experience.At least 4 years of experience with programming in C++ and Rust, with a strong background in memory safety, multi-threaded system architecture, or raw data stream manipulation.Proven ability to onboard quickly, deliver and improve complex software projects.Proven track record of independently scoping and landing complex features within tight release windows.Excellent written and verbal communication skills.
You can validate your progress and decisions and communicate them clearly.Bonus Points:You have already contributed to the Mozilla mission and the codebase.Experience working within the browser space (Gecko, Chromium, WebKit) or web engine runtime abstractions.Experience or high interest in designing or leveraging ML pipelines to automate internal developer workflows.Deep understanding of web architecture, the privacy/security model of the web, and client-side data structures.Knowledge of basic statistical modeling.Proficiency with Python and SQL.What You'll GetGenerous performance-based bonus plans to all eligible employees - we share in our success as one teamGenerous retirement contributions with 100% immediate vesting (regardless of whether you contribute)Quarterly all-company wellness days where everyone takes a pause togetherCountry specific holidays plus a day off for your birthdayOne-time home office stipendAnnual professional development budgetQuarterly