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

Remote CanadaContract2026-10-20 → 2026-11-10

Core

Improve the health of the Firefox Session History area by writing and fixing tests to enhance coverage and Gecko correctness.

Role type

Senior IC browser-engine software engineer (C++/JavaScript)

Builds

Web-Platform tests and Gecko mochitests for the Firefox DOM Core

Domain

Browser engine development (Firefox/Gecko)

Required skills

C++ development, JavaScript for automation, browser-engine codebase experience, debugging in large codebases, code review

Preferred skills

Prior contributions to Gecko or major browser engines, familiarity with Web Platform Tests

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About Mozilla

Mozilla exists to build the Internet as a public resource accessible to all because we believe that open and free is better than closed and controlled. When you work at Mozilla, you give yourself a chance to make a difference in the lives of Web users everywhere. And you give us a chance to make a difference in your life every single day. Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online.

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