Senior Mobile Engineer, iOS

Mozilla·Remote USRemotesenior

In short

→Desarrollar y mejorar la app móvil de Thunderbird en iOS con enfoque en rendimiento y seguridad.
→Trabajar en un equipo pequeño y global, colaborando con otros ingenieros y contribuyentes de código abierto.
→Destaca por ser un rol técnico clave en la expansión de Thunderbird más allá del escritorio, hacia móviles y servicios pagos.

Proficiency in English is required for collaboration with global teams.

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What they ask for

✓Experiencia sólida en desarrollo iOS con Swift y UIKit.
✓Conocimiento profundo del código base y arquitectura de aplicaciones móviles.
✓Capacidad para resolver problemas complejos de rendimiento, seguridad y compatibilidad.
✓Habilidades sólidas en pruebas unitarias, de integración y automatización.
✓Experiencia en revisión de código y guía técnica a otros desarrolladores.
✓Conocimiento de principios de diseño de software escalable y mantenible.

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SwiftUIKitXcodeGitCI/CDUnit TestingIntegration TestingAutomated TestingJIRAConfluence

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Why Thunderbird? Thunderbird is one of the world’s most trusted open-source email applications, empowering more than 20 million people globally. At MZLA, the team behind Thunderbird, we build privacy-respecting communication and productivity tools that help people manage their digital lives while staying in control of their data. We are open source by design. Our products are developed transparently and in collaboration with a global community of contributors, and that same spirit shapes how we work: collaboratively, inclusively, and with a shared commitment to putting users first. We are a small but growing company of 60+ people distributed across seven countries. As Thunderbird evolves beyond a single desktop application, we are expanding across desktop, mobile, paid services, and new product experiences that help people and organizations work more effectively without giving up control to big tech ecosystems. Our revenue model combines user donations, which help keep Thunderbird’s apps freely available, with paid services that cover the costs of hosted offerings while supporting long-term sustainability and continued innovation. A note about MZLA and Mozilla: MZLA Technologies Corporation is the nonprofit-owned company behind Thunderbird and part of the Mozilla family. MZLA is separate from Mozilla Corporation and has its own compensation programs, benefits, and employment policies. To learn more, visit www.thunderbird.net The opportunity The Senior Software Engineer, iOS is an experienced individual contributor who brings deep iOS expertise to the design, development, and evolution of Thunderbird’s iOS application. This role will continue to contribute to Thunderbirds effort to develop the iOS app and establish a strong technical foundation for the product. You’ll work closely with mobile engineers, product management, UX, and other partners to deliver a high-quality iOS experience that meets high standards for performance, reliability, accessibility, security, and maintainability. You’ll play an important role in delivering exceptional user experiences for Thunderbird’s global user base by translating product needs into thoughtful technical solutions and ensuring your work aligns with MZLA’s mission and the objectives of the Thunderbird Project. You’ll also collaborate with open-source contributors and mobile engineers across the broader Mozilla ecosystem. What you’ll do • Build and refine Thunderbird’s mobile products and platform architecture. • Improve scalability, performance, reliability, and user experience. • Develop a deep understanding of the codebase and architecture to confidently make changes across the entire stack. • Maintain strong debugging and testing practices across unit, integration, and automated testing. • Review code and guide improvements to architecture, testing, and development best practices. • Independently resolve complex issues involving performance, security, and cross-platform integration. • Monitor application health and address issues before they escalate. • Document technical decisions, system architecture, and team processes. • Own assigned projects, collaborating cross-functionally, from investigation and planning through development, validation, and delivery.

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