At a glance
Work style
Fully remote
Level
Senior
Open to
United Kingdom
Posted
October 20, 2026
Skills mentioned
Check the full description before you apply.
About the role
The role
You will help the Firefox DOM Core team improve the health of the Session History area. You will write tests to improve the coverage; you will fix tests and/or problems to improve the Gecko correctness.
Responsibilities
Write Web-Platform tests to improve the coverage, and Gecko mochitests as needed
Fix the problems and pass the tests to improve the Gecko correctness
Work through code review with the relevant Gecko module owners and iterate to landing
Definition of done
Improved Session History test coverage and code correctness in Gecko, measured by passed test cases, allowing the team’s senior engineers to focus on security, performance and strategic projects.
Required qualifications
Substantial experience in a browser-engine codebase or in automating for a browser-engine, ideally Firefox/Gecko.
Solid Javascript and applying that language skill to write automated tests.
Proficiency in and experience developing software in C++.
Strong debugging skills in a mature larget codebase.
Comfort working in the open: public bugs, code review, and upstream landing.
Preferred
Prior contributions to Gecko or another major browser engine.
Familiarity with web standards and Web Platform Tests.
How this job compares
- 1,628 remote engineering & it jobs are open here right now.
- We first listed this job 14 days ago.
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