Fullstack Engineer; Mobile

Own the app that captures the real-world data behind the largest AI and robotics models.

Hub is one of the fastest-growing data companies, providing real-world training data to the largest AI and robotics companies. Based in San Francisco and São Paulo, and backed by Y Combinator and top VCs, our mission is to advance embodied AGI through real-world data and research.

You own the Hub mobile app, the main way our contributors record data every day, and the backend it talks to. You understand why it matters to the business as much as how it works. You also jump onto our other software projects as they come up: we hire builders, not specialists.

The mobile app, end to end: recording, sensor capture, uploads, and releases on the App Store and Google Play.

Native capture code on iOS and Android: camera, ARKit and ARCore, IMU sync and video encoding, built to the tight technical specs of top AI labs.

Reliable recording and uploads on any phone, including budget Android devices, with multi-gigabyte clips that survive a locked screen or a killed app.

The backend the app talks to: APIs, data flows and the infrastructure that keeps them fast as we scale from 150K+ to 1M+ users.

Our other software projects as they come: contributor and partner platforms, internal tools, new products.

Turning what the team needs this week into features, and deciding what not to build.

• 3+ years as a software engineer, including at least 2 shipping a React Native app in production on iOS and Android.
• You're comfortable going down into native code (Swift, Kotlin) when the app needs it: camera, sensors, background tasks.
• You're fullstack: you build backend APIs as comfortably as screens.
• A solid technical education. What matters most to us is what you've built.
• Proof you're a builder: apps with real users or revenue, hackathons won, a system you hacked, projects you shipped on your own.
• Active programming you can show: real Git Hub contributions, open-source work, side projects.
• Agentic engineering as a craft. You run several agents in parallel, with a harness you've tuned, and give them a way to check their own work.
• Fluent English, spoken and written.
• Available to start within a month ediate is ideal.
• Ready to commit fully to our scale-up phase, with strong ownership and focus.

• French, spoken and written. A big plus.
• Business sense: you've been a founder, an early engineer at a startup (ideally YC), or added business training to an engineering degree.

• Mobile:
  React Native and Expo in Type Script, one codebase for iOS and Android, native modules in Swift and Kotlin for camera, ARKit and ARCore, IMU sync and background uploads.
• Backend:
  Python, FastAPI, Postgres, React, Docker, AWS and S3, versioned REST APIs.
• Data: multimodal pipelines at petabyte scale, from capture to delivery in MCAP and LeRobot.
• Everything built in-house, not assembled SaaS.

• €60,000 to €80,000 yearly salary ($70,000 to $90,000).
• Remote. Based in France ideally, and we're open to candidates elsewhere.
• Direct work with the founders and with top AI labs.

• A short application read by the team. We open your Git Hub and handles first.
• A first conversation about you, Hub and the role.
• A technical conversation with our engineering team.
• An answer within 48 hours.