Mozilla
Senior Software Engineer, WebExtensions
Remote Canada · Senior
Sponsorship not specified$104k-$139kDetected 27 days ago
JavaScriptRustC++HTMLAndroidCode ReviewAPI DevelopmentCommunication
About the role
- Mozilla Corporation is the non-profit-backed technology company that has shaped the internet for the better over the last 25 years.
- We make pioneering brands like Firefox, the privacy-minded web browser.
- Now, with more than 225 million people around the world using our products each month, we're shaping the next 25 years of technology and helping to reclaim an internet built for people, not companies.
Responsibilities
- Implement and maintain WebExtensions APIs and Addon Management, balancing power, safety, and performance, as well as user interfaces in Firefox.
- Collaborate with product managers, QA, and the AMO engineering team to deliver features end-to-end.
- Support extension developers by helping diagnose issues and improving tooling/documentation.
- Along with thousands of volunteer contributors and collaborators all over the world, Mozillians design, build and distribute open-source software that enables people to enjoy the internet on their terms.
- As a WebExtensions Engineer, you will help implement new extension capabilities, improve existing APIs, and ensure that extensions remain reliable across Firefox.
- 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.
- Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online.
Requirements
- 4+ years of professional experience in software development.
- Strong proficiency in JavaScript, DOM APIs, HTML, and CSS.
- Familiarity with modern browser architecture and debugging tools.
- Experience with API design and integration.
- Ability to navigate and learn from large codebases.
Nice to have
- Experience with Firefox internals, C++ or Rust.
- Familiarity with Android or GeckoView development.
- Knowledge of web security principles.
- Contributions to open source projects, especially in browser or extension development.
Compensation
- Annual professional development budget
Benefits
- Generous performance-based bonus plans to all eligible employees - we share in our success as one team
- Rich medical, dental, and vision coverage
- Generous retirement contributions with 100% immediate vesting (regardless of whether you contribute)
- Quarterly all-company wellness days where everyone takes a pause together
- One-time home office stipend
- Quarterly well-being stipend
- Considerable paid parental leave
- Employee referral bonus program
- Other benefits (life/AD&D, disability, EAP, etc. - varies by country)
- Commitment to diversity, equity, inclusion, and belonging
Company info
- This means we aren't beholden to any shareholders - only to our mission.
- 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.
Visa & Work Authorization
- omestic partner status, disability, sexual orientation, age, genetic predisposition, medical condition, marital status, citizenship status, military or veteran status, or any other basis covered by applicable laws
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This listing is sourced directly from Mozilla's careers page and normalized into a canonical job model.