Senior Contract C++ / JavaScript Software Engineer (Browser Engine)

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. Why Mozilla? At Mozilla, we’re serving humanity—by maintaining a safe, open internet—while also helping the individual humans employed here to reach their personal and professional goals. With a relatively small team serving hundreds of millions of people, a culture of exploration, and a commitment to mentorship, opportunities abound to learn and grow. Our values drive our actions Purpose is built into our work, with our mission driving every decision We challenge assumptions, the status quo, ourselves, and each other We are transparent: in our code, our business partnerships, and our everyday interactions We seek out people from diverse backgrounds and with perspectives different from our own We pair purpose with performance and put people ahead of profit Our impact is global 1000+ paid staff from over 30 countries Thousands of volunteer contributors across six continents 2 global offices: Berlin and Toronto 9 coworking space locations: San Francisco, San Mateo, London, Paris, Portland, Tulsa, Vancouver, Chicago, and Bellevue Hundreds of home offices globally Our benefits are world-class Flexible work environment (majority of Mozillians work remotely) Industry-leading paid parental leave (up to 26 weeks of fully paid leave for childbearing parents and up to 12 weeks for non-childbearing parents) Reimbursement for professional development (up to $3,000/year) A work setup including the latest hardware and software of your choice