Senior Firefox Add-Ons Engineer at Mozilla

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(14 open jobs)

Our mission is to ensure the Internet is a global public resource, open and accessible to all.

Job title
Senior Firefox Add-Ons Engineer
Job listing last updated at
Jun 20, 2019
Job listing location
Mountain View, San Francisco, Portland, Toronto, Vancouver, Berlin, London, Paris, Remote US, Remote Canada, Remote Germany, Remote Europe
Job listing source
Job listing link
External link
Bay Area company location: 2 Harrison St #175, San Francisco CA

Job description

Help define and build the next generation of the browser extension platform as a member of the Add-ons Engineering team. The Add-Ons team at Mozilla maintains the parts of Firefox that support browser extensions, which give users a way to customize Firefox. We work with extension authors, users, and other Firefox engineers to enable a variety of extensions while ensuring that Firefox remains safe and fast when extensions are active.


Our team is geographically-distributed, and working with other Firefox teams in the open is the norm. You'll be responsible for solving problems of different sizes and upholding quality standards by writing code, tests, and specifications as well as participating in code reviews. You'll also interact with real users in the community, using their input—along with prototypes and data from Mozilla—to file bug reports, inform feature designs, and assist strategic decisions. Most importantly, you'll contribute to making the Web Platform safer, faster, and more robust on the only independent browser dedicated to an open Internet.


As a Senior Firefox Add-ons Engineer here at Mozilla, here's what you'll do:

  • Debug and fix problems in Firefox related to the extensions implementation.
  • Work with others (both inside and outside of Mozilla) to define new extension capabilities as well as changes to existing ones, with an emphasis on improving safety and performance for end users.
  • Collaborate with other engineering teams to extend Firefox features and drive standards for web extensions.


We're looking for people who have:

  • Proficiency programming in Javascript (5+ years experience)
  • Experience working with and building APIs (minimum 5 years)
  • A solid understanding of the web platform (JS, HTML, CSS, DOM)
  • Excellent written and verbal communication skills in English
  • Ability to learn and navigate a large and complex multi-language code base


Other things that might make you stand out:

  • Experience with browser extensions
  • Experience with or knowledge of the internals of browser processing
  • Experience developing in C++ and/or Rust
  • Experience developing for Android devices
  • Experience in software security analysis


About Mozilla

Mozilla exists to build the Internet as a public resource accessible to all because we believe that open and free is better than closed and controlled. When you work at Mozilla, you give yourself a chance to make a difference in the lives of Web users everywhere. And you give us a chance to make a difference in your life every single day. Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online.

We are an equal opportunity employer and value diversity. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.


Group: C


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