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Principal Engineer

We're not building better GPS. We're building the new primitive for verifying where someone actually is. In the age of AI, proving physical presence at a specific place is the best bet we have to establish reality, identity, and legality.

You cannot be in two places at once, but every digital signal that attempts to prove that fact is compromised. GPS spoofs with a one-click app. IP addresses yield to any VPN. Credentials get phished. 2FA gets bypassed. AI fabricates voices and faces at scale. The digital is cheap to manipulate. The physical is not.

Why now?

Money has followed a clear pattern: add a new kind of physical presence and remove both friction and risk. You sign the check. You swipe the card. You tap the device. Each breakthrough gave the financial system a new way to read the real world.

Then transactions went digital and that layer disappeared. The result is another password, another 2FA, another face scan … while cyber fraud now rivals the third largest economy on earth and is growing faster than global GDP.

We have a robust running prototype, partnerships that will bring scale, and core, differentiated sensor fusion technology validated in extensive GPS-denied field operations with elite military units.

The Role

This role requires a hacker state of mind. You will own the entire system, frontend to backend: policy composition in Magistrate, the developer API, on-device sensor fusion, the proof generation chain, and the signed token a customer’s server verifies with a public key. Your code defines every layer.

5+ years of professional engineering experience. Competitive compensation and equity. Work from the office in London with the CEO and help build an extraordinary team.

The system you will build has three components. You own all of them:

  • Magistrate (policy frontend): Customers describe their use case. Magistrate maps it to Octet primitives – presence, colocation, geofence, jurisdiction, sybil resistance – and compiles executable policy shipped to the SDK. You build the composition surface, the primitives catalog, and the compiler.

  • Octet SDK (device): Reads onboard sensors (accelerometer, gyroscope, magnetometer, barometer), combines them with environmental signals (GPS, WiFi, cell topology), evaluates compiled policy, and produces a signed proof. All computation on device. Hardware-isolated signing via TEE. You own ingestion, physics validation, ML inference, and proof generation.

  • Customer infrastructure: The signed proof ships to the customer’s endpoint. Their public key verifies the signature. No Octet server in the loop. You build the APIs, SDKs, and integration tooling.

Responsibilities

  • Time-varying signal processing: Build systems that ingest, validate, and reason over noisy, continuous data. Not just inertial sensors – RF, barometric, network topology, anything that changes over time and can anchor a device to a place.

  • On-device ML: CTO and Co-Founder Suvrit Sra (23,000 citations, MIT/TUM Professor) writes production code. You will work directly with Suvrit to take working models and harden them: fusing multimodal sensor data with signals of opportunity to produce a proof of presence. Battery, latency, and memory constraints are yours to solve together.

  • Proof pipeline: Work with the Cryptography Lead on the hardware-backed signing layer and zero-knowledge proofs. You do not need to invent new math. You need to reason about how these primitives compose and integrate them cleanly.

  • Developer experience: APIs, SDKs, proof metering, telemetry, key management, documentation. The developers who integrates Octet should never need to call us.

  • Shipping: Drive the first SDK releases. Ship fast and often.

  • Team: Mentor early hires. Help set the engineering culture.

Why roboticists have a natural edge

The best candidates tend to come from robotics, autonomous systems, navigation, or spatial computing. These fields produce engineers who make complex systems work under severe constraints and who learn from noisy physical-world signals. If you have fused sensor data, reasoned under uncertainty, and shipped under hardware constraints, you already think the way this problem demands. If you don’t come from these fields but know you can do important work at Octet, tell us why. We want to hear from you.

Qualifications

  • Full-stack systems engineering: You have built and shipped multi-layer systems. You move between mobile, server, and embedded in the same week.

  • Time-varying data: Sensor fusion, state estimation, control systems, telemetry, financial time series; any domain where you extract signal from high-dimensional, noisy, time-varying inputs.

  • Mobile platforms: Fluency in Android or iOS at the systems level, or a convincing argument for why you will get there fast.

  • Founder mentality: You ship undefined programs. You own what you build.

  • Bonus: TEEs, verifiable compute, Secure Enclaves, StrongBox, ZKPs.

About Octet

The founders built and exited a venture-backed company together. We know what to do and what not to do. Octet is our once in a lifetime opportunity to build a company that shapes the modern world, going after one of the most significant problems on earth in a way that no one else is. We have worked together for a decade: CEO Benjamin Fels (ex-derivatives trader, built first-of-a-kind AI for financial markets and mission-critical supply chains); COO Drew Arenth (edge tech and logistics); CTO Suvrit Sra (MIT and TUM Professor, €5M Humboldt Prize for AI). Backed by Variant, ex/ante, hivemind and angel investors in leadership at World, Coinbase, and quantitative hedge funds.


Credentials are stolen. Faces are synthesized. Location pings are spoofed. Physical presence is the one signal that cannot be faked. No one has made it programmable.

Join us to build the primitive. → careers@octetproof.com