Senior Product Engineer, Hardware at SageOx · LumiJobs
senior
H1B: no
Responsibilities
We're breaking the trail toward a world where humans and AI agents work as one team — and increasingly, part of that world is physical hardware. The Ox Dot is our first device: a small, always-there presence that gives the hivemind a body in the room. It's real, it's shipping, it's the hardest and most unforgiving surface we build on — and it's one of several hardware bets we're weighing for what comes next.
We're looking for a full-stack engineer whose center of gravity is our hardware — the first hire dedicated to it. A large portion of your time will be on the Ox Dot today: making it stable, making it fast and safe to change, and building the machine that lets a small team (and a fleet of agents) develop hardware the way we already develop software. The rest is genuinely full-stack — you'll write the cloud services the device talks to, build the app and web experiences people actually use, and stitch the whole thing together, from firmware in the field to the pixels on the screen. And we move fast: in a few months the Dot may not be the thing we're building at all. You're someone who flexes with that — bringing up a device from another manufacturer, or picking up a different corner of the stack entirely, without missing a beat.
The Problem You'll Own
Building on the Dot is genuinely hard, and we leap in anyway — that's the job. But the hard part can swallow the day: a change lands, something unrelated breaks, and hours disappear into a bisect, because nothing is exercising the Dot deeply and around the clock to catch a regression the moment it happens. The result is that we don't innovate nearly as much as we could — the challenge of debugging keeps stealing the oxygen.
Your job is to change that. You'll stand up a hardware test lab — a small fleet of real devices under automated QA around the clock — so a change is either green or it isn't, and a regression surfaces the moment it lands, not days later. When debugging stops eating the day, the whole team gets to pour that energy back into building the next thing.
And the destination is big: we're building toward fleets of millions of customer devices in the field. You can't run at millions when every change risks a days-long debug — the small fleet on the bench is how we earn the confidence to get there.
Drive firmware and hardware development. Today that's the Ox Dot — a small audio device: boot, memory, audio pipeline, connectivity, the whole stack that has to Just Work in someone's home or office. Tomorrow it's whatever device we choose next.
Build the development harness. The single highest-leverage thing here isn't a feature — it's the tooling that lets an agent drive a real device end-to-end: flash, exercise, observe, assert, recover, repeat. You'll extend and reinvent the APIs that make a physical device agent-operable.
Stand up 24×7 automated hardware testing. A small fleet of real devices under continuous, unattended test. Behavior-Driven Development (BDD) scenarios as the source of truth for "does the device actually do the thing," running on silicon, not just in a simulator.
Run the agentic software factory. Get one agent operating one device with zero humans in the loop — then a fleet of agents developing, exercising, and self-triaging the bench devices in parallel, filing what they find. This is the factory: it produces software and confidence, not units on a line — and it's how a small team keeps a fleet of millions healthy.
Own OTA and the fleet. Ship firmware safely to devices already in customers' hands — staged rollout, health-gated updates, and A/B rollback so a bad update never bricks a device. At millions of devices in the field, the update pipeline is the product.
Write cloud services and user-facing experiences. The device is only half of it — you'll build the cloud services it talks to and the app and web experiences people actually use (memory and agent systems, auth, real-time streaming), and keep those seams honest against our digital twins.
Qualification
You've built on real hardwareYou're a tinkerer and a hardware hackerYou think in systemsYou build and ship on your ownBonusYou Might Not Be A Fit IfWe'll say this plainly
Required
You use agentic AI coding as a daily practice, not an experiment. Claude Code (or equivalent) is how you already work, on hardware and everything else.
You build the system that builds the code. Harnesses, loops, specs, guardrails — you bring the judgment and direction, and you're at ease reviewing what an agent wrote rather than typing every line yourself.
7+ years building and shipping production software. This is a senior role, and the first one dedicated to our hardware. You’ve owned systems end to end, lived with your own decisions in the field, and know which corners are safe to cut — and which ones brick a device.
You've built on real hardware. A shipped consumer product, or the firmware for a device you hacked together on your bench — either counts. What matters is you've built some complex code that runs on a physical thing, not the logo on the box.
You're a tinkerer and a hardware hacker. You reach for a logic analyzer and a soldering iron, and you think outside the box about how to make a device controllable, observable, and abusable by automation.
You think in systems, not functions. You see the whole loop — device, harness, cloud, agent — and you build the thing that makes the loop tighten.
You build and ship on your own. Side projects, finished and in the world. Active open-source contribution is a strong signal.
You're willing to bet on unproven approaches when the proven one is too slow.
Bonus, not required: you've led before. Directing a fleet of AI coworkers through a hard problem draws on the same muscle as directing a team through one — decompose, delegate with intent, review what comes back, know when to step in and do it yourself.
You Might Not Be A Fit If
We'll say this plainly, because it's the crux of the role — this job assumes an AI-native way of working. You may not be a fit if:
Your instinct is to hand-drive every test on the bench yourself, and the idea of an agent doing it makes you uneasy.
