> Markdown version of [/jobs/ext/1684948-software-engineer](https://www.wearedevelopers.com/jobs/ext/1684948-software-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

---

# Software Engineer

- **Company:** Mozilla Corporation
- **Location:** Madrid, Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** Microsoft Windows, Application Programming Interfaces (APIs), Apple Mac Systems, C++ (Programming Language), Code Review, Computer Programming, Firefox, Windows API, Systems Integration, Data Analytics
- **Published:** July 18, 2026
- **Apply:** https://www.adzuna.es/contact-us.html

## About the Role

A Senior Software Engineer contributes to architectural discussions, and driving feature development within a team.
At Mozilla, Senior Engineers are expected to work independently on scoped projects, collaborate closely with peers, and play a key role in delivering high?quality software that aligns with team goals.What You'll DoContribute to the development and improvement of Firefox features related to installs, updates, and OS integrations.Help implement enhancements to the Firefox installation and update experience, using data insights to guide development.Tackle platform?specific challenges in low?level operating system integration on Windows and/or macOS.Collaborate with your manager and teammates to scope and prioritize work in alignment with the team's goals.Participate in code reviews and contribute to technical discussions with peers.Take ownership of complex bugs and lead efforts to improve the Firefox experience for hundreds of millions of users.Work closely with your geographically distributed team in a highly collaborative environment.What You'll Bring3-5 years
experience as Software EngineerExperience with systems?level programming on at least one major platform (Windows, macOS).
Solid programming skills in C/C++.
Effective communicator and collaborator, especially in distributed teams.Ability to break down technical work and make steady progress within project timelines.A collaborative mindset and a desire to contribute to team success.Bonus PointsProgramming experience in Rust.Experience working with Windows and/or macOS APIs at a low level (e.g., Win32, Cocoa).

## Description

Along with thousands of volunteer contributors and collaborators all over the world, Mozillians design, build and distributeopen?sourcesoftware that enables people to enjoy the internet on their terms.About This Team
The Firefox team is a community of engineers who care deeply about delivering the fastest, friendliest, most usable browser possible.
We are responsible for making the things you see in the browser work securely, quickly, and well!
Desktop Integrations is a cross?functional team that focuses on updates, installs and integrating Firefox with different OS platforms.
As part of the Desktop Integrations team, you will be responsible for all things related to OS integration (particularly Windows and macOS) and helping us grow our user base.Our team is geographically distributed, and working in the open is the norm.
We contribute to the code driving the Firefox browser on a number of desktop platforms.About The Role


## Related Videos

- [Explore new web features before everyone else](https://www.wearedevelopers.com/videos/316-explore-new-web-features-before-everyone-else)
- [How we built an AI-powered code reviewer in 80 hours](https://www.wearedevelopers.com/videos/1511-how-we-built-an-ai-powered-code-reviewer-in-80-hours)
- [WeAreDevelopers LIVE – AI and Privacy, On-Device AI and More](https://www.wearedevelopers.com/videos/1779-wearedevelopers-live-ai-and-privacy-on-device-ai-and-more)
- [Are Code Reviews Worth It? Insights from 16 Years of Review Data](https://www.wearedevelopers.com/videos/1135-are-code-reviews-worth-it-insights-from-16-years-of-review-data)
- [WeAreDevelopers LIVE - CSS or BS?](https://www.wearedevelopers.com/videos/1850-wearedevelopers-live-css-or-bs)
- [Build a CI/CD pipeline to automate code reviews and ensure code quality](https://www.wearedevelopers.com/videos/349-build-a-ci-cd-pipeline-to-automate-code-reviews-and-ensure-code-quality)

## Related Articles

- [The Ultimate Software Engineer Career Path Guide for 2023](https://www.wearedevelopers.com/magazine/146-the-ultimate-software-engineer-career-path-guide-for-2023)
- [What is Software Engineering?](https://www.wearedevelopers.com/magazine/289-what-is-software-engineering)
- [Is Software Engineering Hard?](https://www.wearedevelopers.com/magazine/448-is-software-engineering-hard)
- [How Much Does a Software Engineer Make? Realistic Software Engineering Salaries](https://www.wearedevelopers.com/magazine/425-how-much-does-a-software-engineer-make-realistic-software-engineering-salaries)
- [Fully Remote Software Engineer Jobs](https://www.wearedevelopers.com/magazine/447-fully-remote-software-engineer-jobs)
- [How Much FAANG Companies Actually Pay Software Engineers in 2025](https://www.wearedevelopers.com/magazine/230-how-much-faang-companies-actually-pay-software-engineers-in-2025)