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Senior Contract C++ / JavaScript Software Engineer Firefox (Browser Engine)
OtherWorkplace — unknown
Published on 2026-10-20
These details were extracted automatically from the original listing. They may not be complete or fully up to date — it's worth checking the original job post.
About this role
Improve Firefox Gecko’s Session History area by expanding test coverage and fixing correctness issues. The work includes writing Web Platform Tests and Gecko mochitests, debugging the browser engine, and taking changes through public code review to landing.
About the company
Mozilla builds open-source products and technologies, including Firefox, that prioritize privacy, security, and an open internet.
The team
Firefox DOM Core team
Stack
C++JavaScriptGeckoFirefoxWeb Platform Testsmochitests
What you'll do
- Write Web Platform Tests and Gecko mochitests to improve coverage
- Fix issues and tests to improve Gecko correctness
- Work with Gecko module owners through code review and landing
What we're looking for
- Substantial browser-engine codebase or browser-engine test-automation experience, ideally with Firefox/Gecko
- Strong JavaScript skills for automated testing
- Proficiency developing software in C++
- Strong debugging skills in a large, mature codebase
- Comfort working in the open through public bugs, code review, and upstream landing
Nice to have
- Prior contributions to Gecko or another major browser engine
- Familiarity with web standards and Web Platform Tests