Maintains and improves Firefox’s Layout code across CSS, page layout, APZ, text, and images. Responsibilities include fixing bugs and regressions, keeping tests green, diagnosing cross-platform issues, conducting code reviews, handling routine upkeep, and participating in planning and web-compatibility meetings. The role requires independent technical leadership in a large, mature, multithreaded C++ codebase.
You will take on the ongoing maintenance and routine engineering work in Firefox’s Layout area (CSS, page layout, APZ, text, images). Working independently at a tech-lead level, you keep the Layout code healthy.
Responsibilities- Own day-to-day Layout maintenance: fix bugs and regressions, keep tests green, handle incoming issues.
- Diagnose and fix Layout problems across platforms (Windows, macOS, Linux, Android).
- Carry code review and routine upkeep so the FTE engineers can focus on other mission critical projects. .
- Join planning and standards / web-compat meetings as needed.
Definition of done
A healthy Layout area, backlog and regressions kept down, with the team’s senior engineers freed to focus on critical Performance and Security issues.
Required qualifications
- Strong C++ (JavaScript and/or Rust a plus).
- Solid CSS and page-layout knowledge.
- Strong debugging and optimization in a multithreaded codebase.
- Able to work independently and lead technically in a large, mature codebase.
- Prior experience in web browser architecture and development.
- Prior Web standards experience.
- Mobile web development, profiling and debugging skills a plus.
- Proven experience in utilization of AI tools (Claude, ChatGPT, etc.) in the investigation, development, debugging, and/or testing of code is a plus.
Hiring Ranges:
Canada Tier 1 Locations
$185,045—$217,700 CAD
Canada Tier 2 Locations
$131,400—$154,600 CAD
Mozilla Toronto, Ontario, CAN Office
366 Adelaide St W. Suite 500, Toronto, Canada, M5V 1R7
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