Senior Software Engineer, Add-Ons

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Software Engineer, Add-Ons based in Canada.

You’ll join a distributed engineering team responsible for a platform that supports a large global ecosystem of browser extensions.
The role combines full-stack development, platform reliability, security, and ecosystem operations.
You’ll build major features while modernizing architecture across developer, reviewer, and moderation workflows.
Your work will help improve the experience for extension developers while maintaining a safe and trustworthy ecosystem for users.
You’ll work closely with engineers, product managers, designers, QA, developer relations, reviewers, and community contributors.
The environment emphasizes open-source collaboration, technical ownership, resilience, and continuous improvement.
This is an opportunity to make meaningful contributions to software used by millions of people worldwide.

• Deliver major features and architectural improvements across the add-ons platform, including automated moderation pipelines, reviewer tools, and developer-facing systems.

• Build and maintain full-stack functionality using React/TypeScript, Django/Python, and MySQL.

• Develop robust observability capabilities and use data-driven insights to improve system performance, reliability, and operational decision-making.

• Strengthen platform reliability through deployments, monitoring, incident response, and proactive improvements to infrastructure and engineering practices.

• Contribute to security and trust initiatives that help maintain a safe and reliable add-ons ecosystem.

• Investigate and resolve issues affecting users and developers, ranging from individual bugs to larger production incidents.

• Modernize developer and reviewer workflows, including submission processes, trust and safety signals, and ecosystem management tools.

• Collaborate with product managers, designers, QA teams, engineers, reviewers, and community contributors to deliver end-to-end improvements.

• Participate in open-source development through pull requests, code reviews, technical discussions, and collaboration with external contributors.

• Share technical knowledge, provide constructive peer feedback, and help other engineers develop their skills.

Requirements

• Demonstrated experience building and maintaining modern web applications in a production environment.

• Strong experience with Python/Django or comparable backend frameworks.

• Solid understanding of web security principles, secure development practices, and application security.

• Experience working across the full software development lifecycle, from feature design and implementation through deployment and operational support.

• Familiarity with cloud infrastructure and production operations; experience with Google Cloud or comparable platforms is an advantage.

• Strong collaboration and communication skills, particularly within distributed and cross-functional teams.

• Ability to navigate ambiguity, investigate unfamiliar problem spaces, evaluate potential solutions, and help shape technical direction.

• Comfortable taking ownership of complex technical work while contributing constructively to team and organizational priorities.

• Commitment to collaborative, inclusive, relationship-focused, and resilient ways of working.

• Experience developing automated security or moderation systems is a plus.

• Contributions to open-source projects are valued.

• Experience building tools or workflows for policy-compliant ecosystem moderation is an advantage.

Benefits

• Generous performance-based bonus opportunities for eligible employees.

• Medical, dental, and vision coverage.

• Retirement contributions with immediate vesting, subject to applicable country-specific programs.

• Quarterly company-wide wellness days.

• Country-specific public holidays plus a day off for your birthday.

• One-time home office stipend.

• Annual professional development budget.

• Quarterly well-being stipend.

• Paid parental leave.

• Employee referral bonus program.

• Additional benefits such as life and accidental death & dismemberment insurance, disability coverage, and employee assistance programs, varying by country.

• Remote and distributed working environment.

• Opportunity to contribute to open-source technology and collaborate with a global community.