Free & open-source email software and productivity solutions for managing your personal and professional communications.
San Francisco, CA
Thunderbird is the leading free and open-source email, calendaring, newsfeed, and chat client with more than 20 million active monthly users across Windows, macOS, and Linux. One of Thunderbird's core principles is the use and promotion of open and decentralized standards. Thunderbird is part of MZLA Technologies Corporation, a wholly-owned subsidiary of the Mozilla Foundation.
Remote · Canada, United States
Build, maintain, and improve Mozilla’s internal developer infrastructure platform, including CI/CD, observability, Kubernetes optimization, environment bootstrapping, and cost optimization. Guide technical decisions, develop agentic workflows and platform features, support cross-functional delivery, and help teams operate services safely and effectively.
Remote · Canada, Germany, United States
Lead the architecture, implementation, reliability, and evolution of infrastructure across hybrid-cloud, data center, and workplace environments. Drive complex cross-team initiatives, improve operations through automation and reliability practices, and provide technical guidance and mentorship.
Remote · Canada, United States
Define and execute the strategy and roadmap for Firefox Desktop search across Windows, macOS, and Linux, including experimentation on search access points, defaults, and suggestions. Partner with business development, data science, engineering, research, and design to deliver differentiated search experiences that balance user needs, privacy, technical constraints, and revenue goals.
Remote · Belgium, Canada, Finland, France, Germany, Netherlands, Spain, Sweden, United Kingdom
Improve Firefox's mobile browser experience, primarily on iOS, by refining usability, performance, reliability, and features while driving user activation and retention. Collaborate with engineering, design, data science, and program management teams; use user feedback and analytics to guide improvements, monitor app health, support store growth, and adapt the product for international markets.
Remote · Canada
Build, maintain, and mature Mozilla’s internal developer infrastructure platform, including CI/CD, observability, Kubernetes optimization, environment bootstrapping, and cost optimization. Guide technical decisions, improve developer productivity through agentic workflows, mentor teammates, collaborate across functions, and develop platform proposals and features.
Remote · Canada
Help develop and maintain Firefox installation, update, and operating-system integration features, with a focus on Windows and macOS. Collaborate with teammates on scoped engineering tasks, participate in code reviews, and identify and fix bugs that improve the browser experience.
Remote · Canada, United States
Define and execute the strategy and roadmap for Firefox Desktop search, leading experimentation across search access points, default experiences, and suggestions to improve engagement and revenue. Collaborate with business development, data science, engineering, research, and design to deliver differentiated search experiences that balance user needs, privacy, technical constraints, and business commitments.
Remote · Canada, United States
Design and implement browser-engine experiments and prototypes, investigating how browser internals affect performance, correctness, and programmatic interaction with web content. Instrument and evaluate changes using repeatable tasks, profiling, and testing, then document results and tradeoffs to inform technical direction.
Remote · Canada, United States
Coordinate Firefox Mobile marketing execution across app store optimization, lifecycle campaigns, product launches, and other growth initiatives. Improve operational consistency and scalability through shared workflows, performance reporting, automation, and AI-assisted processes.
