About the company
Terra is the health operating system. We make it easy for developers and AIs to build on health data. hundreds of wearables, sensors, labs, and health apps — connected, normalized, and made intelligent through a single platform. 1,000s of developers and AI labs build on Terra today. we process 15+ billion health data events per year. and we are just getting started.

The health OS
Health data is fragmented. every device, every app, every sensor speaks a different language. we built the health OS to solve that — a full-stack platform that turns raw, messy, siloed health data into something developers and AIs can reason over, build on, and ship with. Terra was founded in 2021 and operates from London, San Francisco, and South Korea. We are funded by Y Combinator (W21), General Catalyst, Samsung NEXT, NEXT Ventures, and many of the world's finest investors. We are a team of engineers, researchers, builders, and designers. we hire people who get things done, think from first principles, and learn ferociously. we default to yes. we ship fast. we hack. we build. we don't do bureaucracy.

The role
You will own and ship core platform systems that power how health data flows through Terra — from upstream data suppliers (wearables, health apps, sensors) into our unified schema, and out to downstream developers and AI consumers via our REST API, Streaming API, and webhooks. This is not a maintenance role. You will build new data connectors, scale real-time streaming pipelines, harden our authentication layer, and design the systems that handle millions of API calls per day. You will work across the entire stack — from low-level data ingestion to developer-facing API surfaces. You will ship fast, iterate through feedback loops, and think in first principles. We don't have layers of process. We have ownership and velocity.

What You Will Build

• Unified API & Data Normalisation: Design and extend the systems that ingest raw health data from 100+ upstream providers (Garmin, Fitbit, Oura, Apple Health, Google Fit, Withings, etc.) and normalise it into Terra's standardised schema.
• Upstream Data Supplier Connector: Architect and build Terra's new upstream connector capability, allowing data suppliers to push data directly into the platform.
• Streaming API: Scale our real-time streaming infrastructure for live sensor data from Apple Watch and BLE/ANT+ devices via websocket listeners.
• Authentication & Developer Experience: Own the authentication layer for both upstream suppliers and downstream developers.
• Webhooks & Event Delivery: Design and harden the webhook delivery system that pushes health data events to downstream consumers.
• Teams API: Contribute to our Teams API — enabling coaches, researchers, and organisations to aggregate and analyse group data.
• Health Scores & Derived Data: Build the backend systems that transform raw health metrics into validated scores backed by research.
• Infrastructure & Reliability: Maintain 99.5%+ uptime on a platform that processes billions of events.

What We Are Looking For

• 5+ years of production backend engineering. You have shipped systems that handle real traffic at scale.
• Deep API design experience. You've built REST APIs consumed by external developers.
• Strong with distributed systems. Message queues, event-driven architectures, stream processing, data pipelines.
• Proficiency in Python and/or Go.
• Database expertise. PostgreSQL, Redis, time-series stores.
• Cloud-native mindset. AWS/GCP. Containers. CI/CD. Infrastructure as code.
• Security-first thinking. Encryption in transit and at rest. GDPR, HIPAA, SOC 2.
• Autonomous and fast. You see the problem, you own it, you ship the fix.

Big Plus
You are an athlete. You train, you compete, you push limits — or at the very least, you are obsessed with quantifying your own data. If you understand the data because you live it, you'll build a better product.

How we work

• Skin in the Game. Everyone has equity. Everyone has stake.
• Deep Work. We protect focus time. No meeting culture.
• Antifragile. We get stronger from chaos.
• Resourceful. We build with what we have and iterate relentlessly.
• Hackers. We build because we can't stop building.

By submitting this application, I agree that my personal data will be collected, processed, and retained by the company solely for the purposes of managing and assessing my candidacy.