Mozilla

Senior Contract Software Engineer (JavaScript) - Firefox

Remote

Senior

REMOTE

Mozilla is hiring a Senior Contract Software Engineer to support the Firefox DOM Core team in improving Session History within the Gecko browser engine. The role focuses on writing and fixing Web Platform tests and mochitest cases, resolving correctness issues in Gecko, and collaborating through public code review to land improvements upstream. Candidates should have strong JavaScript and C++ skills and experience working in a browser-engine codebase.

JavaScript

C++

Browser engine development

Automated testing

Web Platform Tests (WPT)

Gecko mochitests

Debugging large codebases

Code review

Open-source contribution workflow

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