Contract Staff Front End Engineer (Web Conference/Screen Sharing)

Mozilla; United States; Remote; USD 154,000 - 168,000; Part time

Job summary

Mozilla is seeking a front-end engineer on a fixed-term contract to implement UX designs for Firefox's screen, window, and tab sharing, delivering a production-ready UI in a large codebase. You'll collaborate with UX and QA, contribute to mozilla-central through public code reviews on Phabricator, and participate in testing with partners to ensure compatibility with major conferencing services.

Requires 4+ years of frontend experience, strong JS/HTML/CSS skills, and comfort working in an

Qualifications

• 4+ years building production user interfaces with JavaScript, HTML, and CSS.
• Ability to implement approved designs faithfully and flag edge cases.
• Experience in large, mature codebases you didn’t write.
• Experience writing automated tests for user interfaces.
• Strong asynchronous written communication across timezones.
• Comfort working in public with Bugzilla and Phabricator.

Responsibilities

• Implement UX designs for Firefox screen, window and tab sharing.
• Build browser UI that is accessible, tested, and localizable.
• Collaborate with UX and QA to validate results.
• Support partner testing with major web conferencing services.
• Land changes in mozilla-central via public code review.

Skills

UI development

JavaScript

HTML/CSS

Automated UI tests

Async written communication

Tools

Phabricator

Bugzilla

Mochitest

WebRTC

Fluent localization

Job description

About the team and role

Mozilla's Web Conferencing team owns the media capture and sharing features that make Firefox work for video calls: screen, window, and tab capture, and the interface users interact with when they share content in Google Meet, Zoom, or Jitsi.

We're bringing a set of screensharing improvements to Firefox. The backend work is complete and the UX has been designed and approved. We're looking for a front-end engineer on a fixed-term contract to implement it and ship it.

What you'll do

• Implement approved UX designs for Firefox's screen, window and tab sharing experience, and see them through to release
• Build browser UI that holds up in a large, widely used codebase: tested, accessible, and localizable
• Work with UX on the cases a design didn't anticipate, and with QA on validating the result
• Support partner testing against major web conferencing services
• Land your work in mozilla-central through public code review on Phabricator

What you'll bring

• 4+ years building production user interfaces with JavaScript, HTML, and CSS
• Experience implementing an approved design faithfully, plus the judgment to flag it when the design meets a case it didn't anticipate
• Ability to get productive quickly in a large, mature codebase you didn't write
• Experience writing automated tests for user interfaces
• Strong asynchronous written communication, since the team is distributed across timezones
• Comfort working in public, since Bugzilla and Phabricator are open

Bonus qualifications

• Prior contributions to Firefox or another open-source browser
• Familiarity with Firefox front-end architecture: browser/, custom elements, XUL, Fluent localization
• Experience with WebRTC or getDisplayMedia
• Accessibility experience with modal dialogs and list navigation
• Experience with Mozilla's test frameworks (browser-chrome, mochitest)
• Experience using AI tooling effectively in front-end development
• Open source environment experience

Hiring Ranges:Canada Tier 1 Locations$145,000—$170,800 CADCanada Tier 2 Locations$154,000—$168,000 USD