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.

Preferred

• 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.