Staff Product Engineer, Enterprise AI

<p><strong>Why Thunderbird?</strong></p> <p><span style="font-weight: 400;">Thunderbird is one of the world’s most trusted open-source email applications, empowering more than 20 million people globally. At Thunderbird, we build privacy-respecting communication and productivity tools that help people manage their digital lives while staying in control of their data.</span></p> <p><span style="font-weight: 400;">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.</span></p> <p><span style="font-weight: 400;">Our small but growing distributed team includes more than 65 people across seven countries. As Thunderbird evolves beyond a single desktop application, we are expanding across desktop, mobile, paid services, AI offerings, and enterprise-facing work to build independent, privacy-respecting alternatives to big tech ecosystems.</span></p> <p><span style="font-weight: 400;">Our revenue model combines user donations, which help keep Thunderbird’s applications freely available, with paid services that cover the costs of hosted offerings while supporting long-term sustainability and continued innovation.</span></p> <p><strong>A note about Thunderbird and Mozilla: </strong><span style="font-weight: 400;">Thunderbird Technologies Corporation is the nonprofit-owned company behind Thunderbird email and a growing portfolio of products. While part of the Mozilla family, Thunderbird is a separate entity from Mozilla Corporation and Mozilla Foundation with its own compensation programs, benefits, and employment policies.</span></p> <p><span style="font-weight: 400;">To learn more, visit <a href="https://www.thunderbird.net">www.thunderbird.net</a> and <a href="https://www.thunderbolt.io">www.thunderbolt.io</a>&nbsp;</span></p> <p><strong>The opportunity</strong></p> <p><span style="font-weight: 400;">Thunderbird is expanding beyond email with Thunderbolt, an open-source AI client designed for organizations that need more control over their data, infrastructure, and model choices.</span></p> <p><span style="font-weight: 400;">We’re looking for a Staff Full-Stack Product Engineer: a full-stack engineer who ships production code and works directly with the partners and enterprise customers adopting Thunderbolt. You’ll spend most of your time in the codebase, building the features, integrations, and customizations that real deployments need. The rest of your time goes to working alongside technical partners to get those deployments running and keep them healthy.</span></p> <p><span style="font-weight: 400;">Thunderbolt is delivered largely through technical partners and systems integrators who own the day-to-day customer relationship. You’ll be the engineer behind them. You’ll understand how a customer’s environment actually works, turn that understanding into working software, and fix the hard problems that need someone who knows the code.</span></p> <p><strong>What you’ll do&nbsp;</strong></p> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">Build and ship full-stack features, integrations, and customer-specific customizations in the Thunderbolt codebase, from front-end UI through APIs, services, and deployment configuration.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Work directly with technical partners and enterprise customers to understand their environments, requirements, and constraints, and turn them into technical plans and working software.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Support pilots, proofs of concept, and early production deployments, including partner-hosted and customer-controlled environments.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Diagnose and fix complex issues across the application, infrastructure, identity and access, integration, and data-access layers, including bugs and regressions that need a code change and a release.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Maintain customer-specific customizations over time so they keep working as the core product evolves.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Spot which customer requests should become general product capabilities, and work with product and engineering to build them that way rather than as one-offs.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Bring real-world deployment feedback into roadmap and prioritization discussions.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Write the documentation, deployment guidance, and runbooks that let partners handle routine issues on their own.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Use AI-assisted development tools thoughtfully to move quickly while keeping strong judgment about quality, security, and maintainability.</span></li> </ul> <p><strong>What you bring&nbsp;</strong></p> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">10+ years of professional software engineering experience, including significant time building and shipping production applications with Staff-level scope and impact.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Strong full-stack engineering skills, including modern TypeScript or JavaScript, component-based front-end frameworks, and back-end services, APIs, and integrations.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Meaningful experience working directly with customers, partners, or systems integrators in a technical capacity where you also wrote the code. Forward deployed, embedded, consulting, and implementation engineering work all count.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Experience building or supporting AI-enabled applications, such as LLM platforms, RAG systems, agents, enterprise search, or data connectors.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Solid understanding of enterprise deployment concerns, including authentication and identity providers, access control, self-hosted and hybrid infrastructure, observability, and reliability.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Judgment about when to build something custom, when to generalize it into the product, and when to push back on a request.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Clear communication skills with both technical implementers and non-technical stakeholders, including being honest about what the product can and can’t do today.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Strong collaboration skills, including experience working closely with product managers, designers, engineers, and other cross-functional stakeholders.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Comfort operating independently in an early-stage product where requirements, architecture, and processes are still taking shape.</span></li> </ul> <p><strong>Bonus points for</strong></p> <ul> <li style="font-weight: 400;"><span style="font-weight: 400;">Experience with self-hosted, private cloud, sovereign, or regulated deployment environments.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Experience with Docker, Kubernetes, CI/CD, and cloud deployment.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Experience working with European enterprise or public sector customers, or with data residency and sovereignty requirements.</span></li> <li style="font-weight: 400;"><span style="font-weight: 400;">Experience supporting security reviews, privacy assessments, or enterprise procurement