Contract Software Engineer - DOM Core Firefox/Gecko

mozilla · Remote · Remote

• Employment typeContract
• Experience levelMid level
• Salary signalSalary not listed
• Last checked9 days ago
• Source valid throughOct 24, 2026

Role Overview

<h2><strong>The role</strong></h2> <p><span style="font-weight: 400;">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.</span></p> <h2><strong>Responsibilities</strong></h2> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">Write Web-Platform tests to improve the coverage, and Gecko mochitests as needed </span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Fix the problems and pass the tests to improve the Gecko correctness</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Work through code review with the relevant Gecko module owners and iterate to landing</span></li> </ul> <h2><strong>Definition of done</strong></h2> <p><span style="font-weight: 400;">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.</span></p> <h2><strong>Required qualifications</strong></h2> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">Substantial experience in a browser-engine codebase or in automating for a browser-engine, ideally Firefox/Gecko.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Solid Javascript and applying that language skill to write automated tests.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Proficiency in and experience developing software in C++.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Strong debugging skills in a mature larget codebase.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Comfort working in the open: public bugs, code review, and upstream landing.</span></li> </ul> <h2><strong>Preferred</strong></h2> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">Prior contributions to Gecko or another major browser engine.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Familiarity with web standards and Web Platform Tests.</span></li> </ul> Find Jobs in Germany on Arbeitnow

Why It Matches

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