Principal Engineer, Backend

Description

We're solving AI's hardest problem: alignment.

The company is the data layer for Physical AI and enterprise, serving as core infrastructure for 300+ of the world's leading AI teams, including Woven by Toyota, Hitachi, Skydio, AbbVie and Dyna, Walden and Agility Robotics. From autonomous vehicles and robotics to sports and healthcare, we're solving AI's hardest problem: turning complex, real-world data into production-ready intelligent systems.

We're a team of founders, scientists, quants, researchers, and former Olympians, who’ve helped build some of the most successful companies in Silicon Valley, and alumni of MIT, Stanford, UC Berkeley, Oxford, Cambridge, and Imperial.

We're looking for exceptional people who want to help build a category-defining company, operating with high urgency and taking real ownership to help shape the future of AI.

Responsibilities

• We're looking for a Principal Engineer to join our Foundations team, the backend backbone that builds the reliable, scalable, fast systems everyone else at the company builds on top of. The team's core challenges sit deep in distributed and data intensive systems.
• The product mindset on this team is different from most of the company: short-term product insight matters less, long-term matters a lot. Our Foundations team plans around how the next 6, 12, and 24 months will look, with an overarching shape to the problem: handling multiple orders of magnitude the data we handle today. This is our most senior individual contributor role. You'll own the hardest architectural calls, make the trade-offs that shape the platform for years, and raise the engineering bar across the company.
• The company is growing rapidly, with our product as the key driver of that growth. A year ago, we were a team of 100, now, we're over 150 and continuing to accelerate. The systems that got us here won't get us to what's next. That's the problem you'll own.
• Design and lead major database and processing-system initiatives
• Design performant protocols and APIs, such as our label-format API, that customers use directly. This work sits across both product and engineering
• Build robust distributed systems and reason rigorously about how they fail and how they behave under load
• Level up engineers across the company through design reviews, pairing, and mentorship, without adding process for its own sake
• Who we're looking for
• You've seen and built more than most. You've personally designed, built, and operated large-scale distributed systems in production, and you've lived with your architectural decisions long enough to know which trade-offs actually matter
• Your impact shows up in the output of the engineers around you, not just your own commits. You make hard things look simple and teach others to do the same
• You want your work to have a tangible outcome for people. You're not satisfied with building products that do not see the light of day
• You are a builder. You enjoy all aspects of building not only software but a complete product, and are comfortable moving across the stack when necessary
• You enjoy problem-solving and thinking from first principles, reach for the simplest solution that works, and know when boring technology wins
• You're happy to own problems without a predefined, clear definition or obvious solution, and are excited to have autonomy to make decisions as you go
• You understand that being a member of a high-performing team requires two things. You contribute your best work and help others contribute their best. You'll always lend a helping hand when needed and level up those around you
• Experience requirements
• 10+ years building large-scale backend infrastructure applications, including several years operating at staff/principal level with company-wide technical influence
• Deep expertise in distributed systems (databases, processing systems, replication, partitioning, queuing, caching) and a rigorous understanding of how they fail and behave under load at scale
• Experience leading large-scale data migrations and system-splitting or re-architecture projects with real customer data on the line
• Experience owning reliability and operations in production, including monitoring, alerting, and DevOps/SRE
• A track record of raising engineering quality across teams through architecture reviews, code reviews, testing, rollout, and monitoring practices
• Demonstrated ability to influence without authority, driving technical alignment across teams in a fast-moving, low-process environment
• Tech stack
• We are technology-agnostic at the company and are not looking for experience across all of these. As long as you're open to learning, please apply.
• Backend: Python
• Frontend: TypeScript and React
• Deployment: Kubernetes
• Infrastructure: GCP
• Machine learning: PyTorch, CUDA, Ray
• Why the company
• Competitive salary, commission, and meaningful equity in a high-growth startup
• Clear, accelerated growth opportunities as the company scales rapidly
• Strong in-person culture: 4 days/week
• Daily team lunches & dinners
• Annual learning & development budget
• Comprehensive health, dental, and vision coverage
• US employees: 18 paid vacation days plus US public holidays
• UK employees: 25 paid vacation days plus UK public holidays
• Frequent travel opportunities across the U.S., London, and Europe
• Bi-annual company offsites & monthly socials
• Operating principles
• High agency
• You see something broken, you fix it or find the person who can. We celebrate the people who solve 90% of a problem before anyone asks.
• Build with care & urgency
• We bear-hug the customer. Former founders and people from fast-moving, high-stakes environments thrive here.
• Self-aware & hungry
• We stay warm, self-aware, and genuinely hungry. We elevate our peers, and ego doesn't last long.
• Invent in real time
• We move toward the ambiguity. We’re pragmatic, resourceful, energized by the fact that there's no playbook.
• If you're looking to do the most meaningful work of your career alongside people who push you to be better, we'd love to meet you.
• Experience: 8+ years
• Visa: US citizen/visa only