Principal Software Engineer, AI Email App

About the Role

There are over 5 billion users using basic applications today such email, notes, tasks, calendar and they're not AI-native. Our mission is to build proactive applications for anyone in the world, who are not used to complex prompting. We aim to bring intelligence to conversations, errands, organising and workflows, with minimal to no prompting.

Our product focuses on achieving high reliability for long-running workflows, persistent context, and real-world task completion. We believe products will greatly reduce hallucinations

Our objective is to organise anyone's life, allowing us all to spend time on valuable and meaningful things

As Principal Software Engineer, AI Email App, you own the engineering layer that turns AI capability into a reliable product. You will shape the architecture across backend services, APIs, and client applications, while leading a small team of senior engineers.

This is a hands-on leadership role. You stay close to the code, make critical architectural decisions, and ensure the system remains fast, reliable, and coherent as it scales.

What You'll Own

• Own the application engineering strategy and execution across backend, mobile, and desktop.

• Design reliable systems for AI-powered workflows, including state, orchestration, tool use, retries, fallbacks, and failure handling.

• Build the APIs and abstractions that connect AI systems to real-world product experiences.

• Lead a small, senior engineering team and raise the technical bar through design reviews, code reviews, and hands-on mentorship.

• Make high-impact trade-offs across latency, reliability, cost, security, and user experience.

• Establish strong production foundations: observability, monitoring, testing, and operational excellence.

• Partner closely with ML leadership to turn model capabilities into robust, shippable product experiences.

• Move quickly while keeping the architecture simple, maintainable, and ready to scale.

What We're Looking For

• Significant experience leading application or product engineering for complex systems.

• Strong hands-on background building and shipping backend systems used in production.

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