Senior Software Engineer (Localization)

Requirements

• Strong experience developing and maintaining libraries and tools using Python and JavaScript.
• Solid understanding of web technologies, APIs, and modern development workflows.
• Experience with open source development practices and community collaboration.
• Ability to collaborate effectively in a distributed team, across time zones and disciplines.
• Excellent communication skills, with an emphasis on clarity and working across technical and non-technical roles.
• Professional fluency in English (written and verbal).
• Commitment to our values:
  • Welcoming differences
  • Being relationship-minded
  • Practicing responsible participation
  • Having grit

Nice to Haves

• Experience with internationalization (i18n) and localization (l10n) concepts, tools, or workflows.
• Programming experience in Rust and C++.
• Fluency in another language and understanding of linguistic diversity (e.g., grammar, plurals, text direction, and cultural conventions).

What You'll Be Doing

• Contribute to the development of Python and JavaScript libraries (such as moz-l10n) and tools that support Mozilla’s localization infrastructure.
• Improve localization and internationalization within the Firefox codebase to make features more adaptable and accessible across languages and regions.
• Collaborate with engineers and program managers to design and implement new Pontoon features.
• Engage with our community of volunteer developers and localizers to support and guide Mozilla’s localization efforts.
• Collaborate effectively with teammates and internal clients across regions and time zones.

Perks and 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
• Country specific holidays plus a day off for your birthday
• One-time home office stipend
• Annual professional development budget
• Quarterly well-being stipend
• Considerable paid parental leave
• Employee referral bonus program
• Other benefits (life/AD&D, disability, EAP, etc. - varies by country)