Contract Software Engineer - DOM Core Firefox/Gecko

Mozilla·Remote France; Remote Germany; Remote UKRemotemid

In short

→Desarrollar y arreglar pruebas para mejorar la corrección y cobertura del historial de sesión en Firefox/Gecko.
→Trabajar con pruebas Web Platform y mochitests, revisando código y colaborando con ingenieros del equipo.
→Destacado: Impacto directo en la salud del motor Gecko, permitiendo a ingenieros senior enfocarse en seguridad y rendimiento.

Comfort working in the open: public bugs, code review, and upstream landing.

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What they ask for

✓Experiencia sólida en un código base de navegador, idealmente Firefox/Gecko.
✓Habilidades sólidas en JavaScript para escribir pruebas automatizadas.
✓Dominio de C++ para desarrollo de software.
✓Capacidad de depuración en un código base maduro y grande.
✓Comodidad trabajando en entorno abierto: bugs públicos, revisiones de código, integración oficial.
✓Habilidades de colaboración y comunicación efectiva en equipos distribuidos.

Don't tick every box? That's normal — your free dossier shows your gaps and how to cover them in the interview.

JavaScriptC++Web Platform TestsmochitestsGeckobug trackingcode reviewupstream landingFirefoxsession history

Who should you write to at Mozilla?

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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.

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